feat(issues): add issue documents and inline editing

Co-Authored-By: Paperclip <noreply@paperclip.ing>
2026-03-13 21:30:48 -05:00
parent 0f3e9937f6
commit 45998aa9a0
32 changed files with 9157 additions and 97 deletions
--- a/cli/src/commands/worktree.ts
+++ b/cli/src/commands/worktree.ts
@@ -83,6 +83,7 @@ type EmbeddedPostgresCtor = new (opts: {
  password: string;
  port: number;
  persistent: boolean;
+  initdbFlags?: string[];
  onLog?: (message: unknown) => void;
  onError?: (message: unknown) => void;
 }) => EmbeddedPostgresInstance;
--- a/doc/SPEC-implementation.md
+++ b/doc/SPEC-implementation.md
@@ -330,6 +330,34 @@ Operational policy:
  - `asset_id` uuid fk not null
  - `issue_comment_id` uuid fk null

+## 7.15 `documents` + `document_revisions` + `issue_documents`
+
+- `documents` stores editable text-first documents:
+  - `id` uuid pk
+  - `company_id` uuid fk not null
+  - `title` text null
+  - `format` text not null (`markdown`)
+  - `latest_body` text not null
+  - `latest_revision_id` uuid null
+  - `latest_revision_number` int not null
+  - `created_by_agent_id` uuid fk null
+  - `created_by_user_id` uuid/text fk null
+  - `updated_by_agent_id` uuid fk null
+  - `updated_by_user_id` uuid/text fk null
+- `document_revisions` stores append-only history:
+  - `id` uuid pk
+  - `company_id` uuid fk not null
+  - `document_id` uuid fk not null
+  - `revision_number` int not null
+  - `body` text not null
+  - `change_summary` text null
+- `issue_documents` links documents to issues with a stable workflow key:
+  - `id` uuid pk
+  - `company_id` uuid fk not null
+  - `issue_id` uuid fk not null
+  - `document_id` uuid fk not null
+  - `key` text not null (`plan`, `design`, `notes`, etc.)
+
 ## 8. State Machines

 ## 8.1 Agent Status
@@ -441,6 +469,11 @@ All endpoints are under `/api` and return JSON.
 - `POST /companies/:companyId/issues`
 - `GET /issues/:issueId`
 - `PATCH /issues/:issueId`
+- `GET /issues/:issueId/documents`
+- `GET /issues/:issueId/documents/:key`
+- `PUT /issues/:issueId/documents/:key`
+- `GET /issues/:issueId/documents/:key/revisions`
+- `DELETE /issues/:issueId/documents/:key`
 - `POST /issues/:issueId/checkout`
 - `POST /issues/:issueId/release`
 - `POST /issues/:issueId/comments`
--- a/docs/api/issues.md
+++ b/docs/api/issues.md
@@ -1,9 +1,9 @@
 ---
 title: Issues
-summary: Issue CRUD, checkout/release, comments, and attachments
+summary: Issue CRUD, checkout/release, comments, documents, and attachments
 ---

-Issues are the unit of work in Paperclip. They support hierarchical relationships, atomic checkout, comments, and file attachments.
+Issues are the unit of work in Paperclip. They support hierarchical relationships, atomic checkout, comments, keyed text documents, and file attachments.

 ## List Issues

@@ -29,6 +29,12 @@ GET /api/issues/{issueId}

 Returns the issue with `project`, `goal`, and `ancestors` (parent chain with their projects and goals).

+The response also includes:
+
+- `planDocument`: the full text of the issue document with key `plan`, when present
+- `documentSummaries`: metadata for all linked issue documents
+- `legacyPlanDocument`: a read-only fallback when the description still contains an old `<plan>` block
+
 ## Create Issue

 ```
@@ -100,6 +106,54 @@ POST /api/issues/{issueId}/comments

@-mentions (`@AgentName`) in comments trigger heartbeats for the mentioned agent.

+## Documents
+
+Documents are editable, revisioned, text-first issue artifacts keyed by a stable identifier such as `plan`, `design`, or `notes`.
+
+### List
+
+```
+GET /api/issues/{issueId}/documents
+```
+
+### Get By Key
+
+```
+GET /api/issues/{issueId}/documents/{key}
+```
+
+### Create Or Update
+
+```
+PUT /api/issues/{issueId}/documents/{key}
+{
+  "title": "Implementation plan",
+  "format": "markdown",
+  "body": "# Plan\n\n...",
+  "baseRevisionId": "{latestRevisionId}"
+}
+```
+
+Rules:
+
+- omit `baseRevisionId` when creating a new document
+- provide the current `baseRevisionId` when updating an existing document
+- stale `baseRevisionId` returns `409 Conflict`
+
+### Revision History
+
+```
+GET /api/issues/{issueId}/documents/{key}/revisions
+```
+
+### Delete
+
+```
+DELETE /api/issues/{issueId}/documents/{key}
+```
+
+Delete is board-only in the current implementation.
+
 ## Attachments

 ### Upload
--- a/docs/plans/2026-03-13-issue-documents-plan.md
+++ b/docs/plans/2026-03-13-issue-documents-plan.md
@@ -0,0 +1,569 @@
+# Issue Documents Plan
+
+Status: Draft  
+Owner: Backend + UI + Agent Protocol  
+Date: 2026-03-13  
+Primary issue: `PAP-448`
+
+## Summary
+
+Add first-class **documents** to Paperclip as editable, revisioned, company-scoped text artifacts that can be linked to issues.
+
+The first required convention is a document with key `plan`.
+
+This solves the immediate workflow problem in `PAP-448`:
+
+- plans should stop living inside issue descriptions as `<plan>` blocks
+- agents and board users should be able to create/update issue documents directly
+- `GET /api/issues/:id` should include the full `plan` document and expose the other available documents
+- issue detail should render documents under the description
+
+This should be built as the **text-document slice** of the broader artifact system, not as a replacement for attachments/assets.
+
+## Recommended Product Shape
+
+### Documents vs attachments vs artifacts
+
+- **Documents**: editable text content with stable keys and revision history.
+- **Attachments**: uploaded/generated opaque files backed by storage (`assets` + `issue_attachments`).
+- **Artifacts**: later umbrella/read-model that can unify documents, attachments, previews, and workspace files.
+
+Recommendation:
+
+- implement **issue documents now**
+- keep existing attachments as-is
+- defer full artifact unification until there is a second real consumer beyond issue documents + attachments
+
+This keeps `PAP-448` focused while still fitting the larger artifact direction.
+
+## Goals
+
+1. Give issues first-class keyed documents, starting with `plan`.
+2. Make documents editable by board users and same-company agents with issue access.
+3. Preserve change history with append-only revisions.
+4. Make the `plan` document automatically available in the normal issue fetch used by agents/heartbeats.
+5. Replace the current `<plan>`-in-description convention in skills/docs.
+6. Keep the design compatible with a future artifact/deliverables layer.
+
+## Non-Goals
+
+- full collaborative doc editing
+- binary-file version history
+- browser IDE or workspace editor
+- full artifact-system implementation in the same change
+- generalized polymorphic relations for every entity type on day one
+
+## Product Decisions
+
+### 1. Keyed issue documents
+
+Each issue can have multiple documents. Each document relation has a stable key:
+
+- `plan`
+- `design`
+- `notes`
+- `report`
+- custom keys later
+
+Key rules:
+
+- unique per issue, case-insensitive
+- normalized to lowercase slug form
+- machine-oriented and stable
+- title is separate and user-facing
+
+The `plan` key is conventional and reserved by Paperclip workflow/docs.
+
+### 2. Text-first v1
+
+V1 documents should be text-first, not arbitrary blobs.
+
+Recommended supported formats:
+
+- `markdown`
+- `plain_text`
+- `json`
+- `html`
+
+Recommendation:
+
+- optimize UI for `markdown`
+- allow raw editing for the others
+- keep PDFs/images/CSVs/etc as attachments/artifacts, not editable documents
+
+### 3. Revision model
+
+Every document update creates a new immutable revision.
+
+The current document row stores the latest snapshot for fast reads.
+
+### 4. Concurrency model
+
+Do not use silent last-write-wins.
+
+Updates should include `baseRevisionId`:
+
+- create: no base revision required
+- update: `baseRevisionId` must match current latest revision
+- mismatch: return `409 Conflict`
+
+This is important because both board users and agents may edit the same document.
+
+### 5. Issue fetch behavior
+
+`GET /api/issues/:id` should include:
+
+- full `planDocument` when a `plan` document exists
+- `documentSummaries` for all linked documents
+
+It should not inline every document body by default.
+
+This keeps issue fetches useful for agents without making every issue payload unbounded.
+
+### 6. Legacy `<plan>` compatibility
+
+If an issue has no `plan` document but its description contains a legacy `<plan>` block:
+
+- expose that as a legacy read-only fallback in API/UI
+- mark it as legacy/synthetic
+- prefer a real `plan` document when both exist
+
+Recommendation:
+
+- do not auto-rewrite old issue descriptions in the first rollout
+- provide an explicit import/migrate path later
+
+## Proposed Data Model
+
+Recommendation: make documents first-class, but keep issue linkage explicit via a join table.
+
+This preserves foreign keys today and gives a clean path to future `project_documents` or `company_documents` tables later.
+
+## Tables
+
+### `documents`
+
+Canonical text document record.
+
+Suggested columns:
+
+- `id`
+- `company_id`
+- `title`
+- `format`
+- `latest_body`
+- `latest_revision_id`
+- `latest_revision_number`
+- `created_by_agent_id`
+- `created_by_user_id`
+- `updated_by_agent_id`
+- `updated_by_user_id`
+- `created_at`
+- `updated_at`
+
+### `document_revisions`
+
+Append-only history.
+
+Suggested columns:
+
+- `id`
+- `company_id`
+- `document_id`
+- `revision_number`
+- `body`
+- `change_summary`
+- `created_by_agent_id`
+- `created_by_user_id`
+- `created_at`
+
+Constraints:
+
+- unique `(document_id, revision_number)`
+
+### `issue_documents`
+
+Issue relation + workflow key.
+
+Suggested columns:
+
+- `id`
+- `company_id`
+- `issue_id`
+- `document_id`
+- `key`
+- `created_at`
+- `updated_at`
+
+Constraints:
+
+- unique `(company_id, issue_id, key)`
+- unique `(document_id)` to keep one issue relation per document in v1
+
+## Why not use `assets` for this?
+
+Because `assets` solves blob storage, not:
+
+- stable keyed semantics like `plan`
+- inline text editing
+- revision history
+- optimistic concurrency
+- cheap inclusion in `GET /issues/:id`
+
+Documents and attachments should remain separate primitives, then meet later in a deliverables/artifact read-model.
+
+## Shared Types and API Contract
+
+## New shared types
+
+Add:
+
+- `DocumentFormat`
+- `IssueDocument`
+- `IssueDocumentSummary`
+- `DocumentRevision`
+
+Recommended `IssueDocument` shape:
+
+```ts
+type DocumentFormat = "markdown" | "plain_text" | "json" | "html";
+
+interface IssueDocument {
+  id: string;
+  companyId: string;
+  issueId: string;
+  key: string;
+  title: string | null;
+  format: DocumentFormat;
+  body: string;
+  latestRevisionId: string;
+  latestRevisionNumber: number;
+  createdByAgentId: string | null;
+  createdByUserId: string | null;
+  updatedByAgentId: string | null;
+  updatedByUserId: string | null;
+  createdAt: Date;
+  updatedAt: Date;
+}
+```
+
+Recommended `IssueDocumentSummary` shape:
+
+```ts
+interface IssueDocumentSummary {
+  id: string;
+  key: string;
+  title: string | null;
+  format: DocumentFormat;
+  latestRevisionId: string;
+  latestRevisionNumber: number;
+  updatedAt: Date;
+}
+```
+
+## Issue type enrichment
+
+Extend `Issue` with:
+
+```ts
+interface Issue {
+  ...
+  planDocument?: IssueDocument | null;
+  documentSummaries?: IssueDocumentSummary[];
+  legacyPlanDocument?: {
+    key: "plan";
+    body: string;
+    source: "issue_description";
+  } | null;
+}
+```
+
+This directly satisfies the `PAP-448` requirement for heartbeat/API issue fetches.
+
+## API endpoints
+
+Recommended endpoints:
+
+- `GET /api/issues/:issueId/documents`
+- `GET /api/issues/:issueId/documents/:key`
+- `PUT /api/issues/:issueId/documents/:key`
+- `GET /api/issues/:issueId/documents/:key/revisions`
+- `DELETE /api/issues/:issueId/documents/:key` optionally board-only in v1
+
+Recommended `PUT` body:
+
+```ts
+{
+  title?: string | null;
+  format: "markdown" | "plain_text" | "json" | "html";
+  body: string;
+  changeSummary?: string | null;
+  baseRevisionId?: string | null;
+}
+```
+
+Behavior:
+
+- missing document + no `baseRevisionId`: create
+- existing document + matching `baseRevisionId`: update
+- existing document + stale `baseRevisionId`: `409`
+
+## Authorization and invariants
+
+- all document records are company-scoped
+- issue relation must belong to same company
+- board access follows existing issue access rules
+- agent access follows existing same-company issue access rules
+- every mutation writes activity log entries
+
+Recommended delete rule for v1:
+
+- board can delete documents
+- agents can create/update, but not delete
+
+That keeps automated systems from removing canonical docs too easily.
+
+## UI Plan
+
+## Issue detail
+
+Add a new **Documents** section directly under the issue description.
+
+Recommended behavior:
+
+- show `plan` first when present
+- show other documents below it
+- render a gist-like header:
+  - key
+  - title
+  - last updated metadata
+  - revision number
+- support inline edit
+- support create new document by key
+- support revision history drawer or sheet
+
+Recommended presentation order:
+
+1. Description
+2. Documents
+3. Attachments
+4. Comments / activity / sub-issues
+
+This matches the request that documents live under the description while still leaving attachments available.
+
+## Editing UX
+
+Recommendation:
+
+- use markdown preview + raw edit toggle for markdown docs
+- use raw textarea editor for non-markdown docs in v1
+- show explicit save conflicts on `409`
+- show a clear empty state: "No documents yet"
+
+## Legacy plan rendering
+
+If there is no stored `plan` document but legacy `<plan>` exists:
+
+- show it in the Documents section
+- mark it `Legacy plan from description`
+- offer create/import in a later pass
+
+## Agent Protocol and Skills
+
+Update the Paperclip agent workflow so planning no longer edits the issue description.
+
+Required changes:
+
+- update `skills/paperclip/SKILL.md`
+- replace the `<plan>` instructions with document creation/update instructions
+- document the new endpoints in `docs/api/issues.md`
+- update any internal planning docs that still teach inline `<plan>` blocks
+
+New rule:
+
+- when asked to make a plan for an issue, create or update the issue document with key `plan`
+- leave a comment that the plan document was created/updated
+- do not mark the issue done
+
+## Relationship to the Artifact Plan
+
+This work should explicitly feed the broader artifact/deliverables direction.
+
+Recommendation:
+
+- keep documents as their own primitive in this change
+- add `document` to any future `ArtifactKind`
+- later build a deliverables read-model that aggregates:
+  - issue documents
+  - issue attachments
+  - preview URLs
+  - workspace-file references
+
+The artifact proposal currently has no explicit `document` kind. It should.
+
+Recommended future shape:
+
+```ts
+type ArtifactKind =
+  | "document"
+  | "attachment"
+  | "workspace_file"
+  | "preview"
+  | "report_link";
+```
+
+## Implementation Phases
+
+## Phase 1: Shared contract and schema
+
+Files:
+
+- `packages/db/src/schema/documents.ts`
+- `packages/db/src/schema/document_revisions.ts`
+- `packages/db/src/schema/issue_documents.ts`
+- `packages/db/src/schema/index.ts`
+- `packages/db/src/migrations/*`
+- `packages/shared/src/types/issue.ts`
+- `packages/shared/src/validators/issue.ts` or new document validator file
+- `packages/shared/src/index.ts`
+
+Acceptance:
+
+- schema enforces one key per issue
+- revisions are append-only
+- shared types expose plan/document fields on issue fetch
+
+## Phase 2: Server services and routes
+
+Files:
+
+- `server/src/services/issues.ts` or `server/src/services/documents.ts`
+- `server/src/routes/issues.ts`
+- `server/src/services/activity.ts` callsites
+
+Behavior:
+
+- list/get/upsert/delete documents
+- revision listing
+- `GET /issues/:id` returns `planDocument` + `documentSummaries`
+- company boundary checks match issue routes
+
+Acceptance:
+
+- agents and board can fetch/update same-company issue documents
+- stale edits return `409`
+- activity timeline shows document changes
+
+## Phase 3: UI issue documents surface
+
+Files:
+
+- `ui/src/api/issues.ts`
+- `ui/src/lib/queryKeys.ts`
+- `ui/src/pages/IssueDetail.tsx`
+- new reusable document UI component if needed
+
+Behavior:
+
+- render plan + documents under description
+- create/update by key
+- open revision history
+- show conflicts/errors clearly
+
+Acceptance:
+
+- board can create a `plan` doc from issue detail
+- updated plan appears immediately
+- issue detail no longer depends on description-embedded `<plan>`
+
+## Phase 4: Skills/docs migration
+
+Files:
+
+- `skills/paperclip/SKILL.md`
+- `docs/api/issues.md`
+- `doc/SPEC-implementation.md`
+- relevant plan/docs that mention `<plan>`
+
+Acceptance:
+
+- planning guidance references issue documents, not inline issue description tags
+- API docs describe the new document endpoints and issue payload additions
+
+## Phase 5: Legacy compatibility and follow-up
+
+Behavior:
+
+- read legacy `<plan>` blocks as fallback
+- optionally add explicit import/migration command later
+
+Follow-up, not required for first merge:
+
+- deliverables/artifact read-model
+- project/company documents
+- comment-linked documents
+- diff view between revisions
+
+## Test Plan
+
+### Server
+
+- document create/read/update/delete lifecycle
+- revision numbering
+- `baseRevisionId` conflict handling
+- company boundary enforcement
+- agent vs board authorization
+- issue fetch includes `planDocument` and document summaries
+- legacy `<plan>` fallback behavior
+- activity log mutation coverage
+
+### UI
+
+- issue detail shows plan document
+- create/update flows invalidate queries correctly
+- conflict and validation errors are surfaced
+- legacy plan fallback renders correctly
+
+### Verification
+
+Run before implementation is declared complete:
+
+```sh
+pnpm -r typecheck
+pnpm test:run
+pnpm build
+```
+
+## Open Questions
+
+1. Should v1 documents be markdown-only, with `json/html/plain_text` deferred?
+   Recommendation: allow all four in API, optimize UI for markdown only.
+
+2. Should agents be allowed to create arbitrary keys, or only conventional keys?
+   Recommendation: allow arbitrary keys with normalized validation; reserve `plan` as special behavior only.
+
+3. Should delete exist in v1?
+   Recommendation: yes, but board-only.
+
+4. Should legacy `<plan>` blocks ever be auto-migrated?
+   Recommendation: no automatic mutation in the first rollout.
+
+5. Should documents appear inside a future Deliverables section or remain a top-level Issue section?
+   Recommendation: keep a dedicated Documents section now; later also expose them in Deliverables if an aggregated artifact view is added.
+
+## Final Recommendation
+
+Ship **issue documents** as a focused, text-first primitive now.
+
+Do not try to solve full artifact unification in the same implementation.
+
+Use:
+
+- first-class document tables
+- issue-level keyed linkage
+- append-only revisions
+- `planDocument` embedded in normal issue fetches
+- legacy `<plan>` fallback
+- skill/docs migration away from description-embedded plans
+
+This addresses the real planning workflow problem immediately and leaves the artifact system room to grow cleanly afterward.
--- a/packages/db/src/migration-runtime.ts
+++ b/packages/db/src/migration-runtime.ts
@@ -17,6 +17,7 @@ type EmbeddedPostgresCtor = new (opts: {
  password: string;
  port: number;
  persistent: boolean;
+  initdbFlags?: string[];
  onLog?: (message: unknown) => void;
  onError?: (message: unknown) => void;
 }) => EmbeddedPostgresInstance;
--- a/packages/db/src/migrations/0028_harsh_goliath.sql
+++ b/packages/db/src/migrations/0028_harsh_goliath.sql
@@ -0,0 +1,54 @@
+CREATE TABLE "document_revisions" (
+	"id" uuid PRIMARY KEY DEFAULT gen_random_uuid() NOT NULL,
+	"company_id" uuid NOT NULL,
+	"document_id" uuid NOT NULL,
+	"revision_number" integer NOT NULL,
+	"body" text NOT NULL,
+	"change_summary" text,
+	"created_by_agent_id" uuid,
+	"created_by_user_id" text,
+	"created_at" timestamp with time zone DEFAULT now() NOT NULL
+);
+--> statement-breakpoint
+CREATE TABLE "documents" (
+	"id" uuid PRIMARY KEY DEFAULT gen_random_uuid() NOT NULL,
+	"company_id" uuid NOT NULL,
+	"title" text,
+	"format" text DEFAULT 'markdown' NOT NULL,
+	"latest_body" text NOT NULL,
+	"latest_revision_id" uuid,
+	"latest_revision_number" integer DEFAULT 1 NOT NULL,
+	"created_by_agent_id" uuid,
+	"created_by_user_id" text,
+	"updated_by_agent_id" uuid,
+	"updated_by_user_id" text,
+	"created_at" timestamp with time zone DEFAULT now() NOT NULL,
+	"updated_at" timestamp with time zone DEFAULT now() NOT NULL
+);
+--> statement-breakpoint
+CREATE TABLE "issue_documents" (
+	"id" uuid PRIMARY KEY DEFAULT gen_random_uuid() NOT NULL,
+	"company_id" uuid NOT NULL,
+	"issue_id" uuid NOT NULL,
+	"document_id" uuid NOT NULL,
+	"key" text NOT NULL,
+	"created_at" timestamp with time zone DEFAULT now() NOT NULL,
+	"updated_at" timestamp with time zone DEFAULT now() NOT NULL
+);
+--> statement-breakpoint
+ALTER TABLE "document_revisions" ADD CONSTRAINT "document_revisions_company_id_companies_id_fk" FOREIGN KEY ("company_id") REFERENCES "public"."companies"("id") ON DELETE no action ON UPDATE no action;--> statement-breakpoint
+ALTER TABLE "document_revisions" ADD CONSTRAINT "document_revisions_document_id_documents_id_fk" FOREIGN KEY ("document_id") REFERENCES "public"."documents"("id") ON DELETE cascade ON UPDATE no action;--> statement-breakpoint
+ALTER TABLE "document_revisions" ADD CONSTRAINT "document_revisions_created_by_agent_id_agents_id_fk" FOREIGN KEY ("created_by_agent_id") REFERENCES "public"."agents"("id") ON DELETE set null ON UPDATE no action;--> statement-breakpoint
+ALTER TABLE "documents" ADD CONSTRAINT "documents_company_id_companies_id_fk" FOREIGN KEY ("company_id") REFERENCES "public"."companies"("id") ON DELETE no action ON UPDATE no action;--> statement-breakpoint
+ALTER TABLE "documents" ADD CONSTRAINT "documents_created_by_agent_id_agents_id_fk" FOREIGN KEY ("created_by_agent_id") REFERENCES "public"."agents"("id") ON DELETE set null ON UPDATE no action;--> statement-breakpoint
+ALTER TABLE "documents" ADD CONSTRAINT "documents_updated_by_agent_id_agents_id_fk" FOREIGN KEY ("updated_by_agent_id") REFERENCES "public"."agents"("id") ON DELETE set null ON UPDATE no action;--> statement-breakpoint
+ALTER TABLE "issue_documents" ADD CONSTRAINT "issue_documents_company_id_companies_id_fk" FOREIGN KEY ("company_id") REFERENCES "public"."companies"("id") ON DELETE no action ON UPDATE no action;--> statement-breakpoint
+ALTER TABLE "issue_documents" ADD CONSTRAINT "issue_documents_issue_id_issues_id_fk" FOREIGN KEY ("issue_id") REFERENCES "public"."issues"("id") ON DELETE cascade ON UPDATE no action;--> statement-breakpoint
+ALTER TABLE "issue_documents" ADD CONSTRAINT "issue_documents_document_id_documents_id_fk" FOREIGN KEY ("document_id") REFERENCES "public"."documents"("id") ON DELETE cascade ON UPDATE no action;--> statement-breakpoint
+CREATE UNIQUE INDEX "document_revisions_document_revision_uq" ON "document_revisions" USING btree ("document_id","revision_number");--> statement-breakpoint
+CREATE INDEX "document_revisions_company_document_created_idx" ON "document_revisions" USING btree ("company_id","document_id","created_at");--> statement-breakpoint
+CREATE INDEX "documents_company_updated_idx" ON "documents" USING btree ("company_id","updated_at");--> statement-breakpoint
+CREATE INDEX "documents_company_created_idx" ON "documents" USING btree ("company_id","created_at");--> statement-breakpoint
+CREATE UNIQUE INDEX "issue_documents_company_issue_key_uq" ON "issue_documents" USING btree ("company_id","issue_id","key");--> statement-breakpoint
+CREATE UNIQUE INDEX "issue_documents_document_uq" ON "issue_documents" USING btree ("document_id");--> statement-breakpoint
+CREATE INDEX "issue_documents_company_issue_updated_idx" ON "issue_documents" USING btree ("company_id","issue_id","updated_at");
--- a/packages/db/src/migrations/meta/0028_snapshot.json
+++ b/packages/db/src/migrations/meta/0028_snapshot.json
--- a/packages/db/src/migrations/meta/_journal.json
+++ b/packages/db/src/migrations/meta/_journal.json
@@ -197,6 +197,13 @@
      "when": 1773150731736,
      "tag": "0027_tranquil_tenebrous",
      "breakpoints": true
+    },
+    {
+      "idx": 28,
+      "version": "7",
+      "when": 1773432085646,
+      "tag": "0028_harsh_goliath",
+      "breakpoints": true
    }
  ]
 }
--- a/packages/db/src/schema/document_revisions.ts
+++ b/packages/db/src/schema/document_revisions.ts
@@ -0,0 +1,30 @@
+import { pgTable, uuid, text, integer, timestamp, index, uniqueIndex } from "drizzle-orm/pg-core";
+import { companies } from "./companies.js";
+import { agents } from "./agents.js";
+import { documents } from "./documents.js";
+
+export const documentRevisions = pgTable(
+  "document_revisions",
+  {
+    id: uuid("id").primaryKey().defaultRandom(),
+    companyId: uuid("company_id").notNull().references(() => companies.id),
+    documentId: uuid("document_id").notNull().references(() => documents.id, { onDelete: "cascade" }),
+    revisionNumber: integer("revision_number").notNull(),
+    body: text("body").notNull(),
+    changeSummary: text("change_summary"),
+    createdByAgentId: uuid("created_by_agent_id").references(() => agents.id, { onDelete: "set null" }),
+    createdByUserId: text("created_by_user_id"),
+    createdAt: timestamp("created_at", { withTimezone: true }).notNull().defaultNow(),
+  },
+  (table) => ({
+    documentRevisionUq: uniqueIndex("document_revisions_document_revision_uq").on(
+      table.documentId,
+      table.revisionNumber,
+    ),
+    companyDocumentCreatedIdx: index("document_revisions_company_document_created_idx").on(
+      table.companyId,
+      table.documentId,
+      table.createdAt,
+    ),
+  }),
+);
--- a/packages/db/src/schema/documents.ts
+++ b/packages/db/src/schema/documents.ts
@@ -0,0 +1,26 @@
+import { pgTable, uuid, text, integer, timestamp, index } from "drizzle-orm/pg-core";
+import { companies } from "./companies.js";
+import { agents } from "./agents.js";
+
+export const documents = pgTable(
+  "documents",
+  {
+    id: uuid("id").primaryKey().defaultRandom(),
+    companyId: uuid("company_id").notNull().references(() => companies.id),
+    title: text("title"),
+    format: text("format").notNull().default("markdown"),
+    latestBody: text("latest_body").notNull(),
+    latestRevisionId: uuid("latest_revision_id"),
+    latestRevisionNumber: integer("latest_revision_number").notNull().default(1),
+    createdByAgentId: uuid("created_by_agent_id").references(() => agents.id, { onDelete: "set null" }),
+    createdByUserId: text("created_by_user_id"),
+    updatedByAgentId: uuid("updated_by_agent_id").references(() => agents.id, { onDelete: "set null" }),
+    updatedByUserId: text("updated_by_user_id"),
+    createdAt: timestamp("created_at", { withTimezone: true }).notNull().defaultNow(),
+    updatedAt: timestamp("updated_at", { withTimezone: true }).notNull().defaultNow(),
+  },
+  (table) => ({
+    companyUpdatedIdx: index("documents_company_updated_idx").on(table.companyId, table.updatedAt),
+    companyCreatedIdx: index("documents_company_created_idx").on(table.companyId, table.createdAt),
+  }),
+);
--- a/packages/db/src/schema/index.ts
+++ b/packages/db/src/schema/index.ts
@@ -24,6 +24,9 @@ export { issueComments } from "./issue_comments.js";
 export { issueReadStates } from "./issue_read_states.js";
 export { assets } from "./assets.js";
 export { issueAttachments } from "./issue_attachments.js";
+export { documents } from "./documents.js";
+export { documentRevisions } from "./document_revisions.js";
+export { issueDocuments } from "./issue_documents.js";
 export { heartbeatRuns } from "./heartbeat_runs.js";
 export { heartbeatRunEvents } from "./heartbeat_run_events.js";
 export { costEvents } from "./cost_events.js";
--- a/packages/db/src/schema/issue_documents.ts
+++ b/packages/db/src/schema/issue_documents.ts
@@ -0,0 +1,30 @@
+import { pgTable, uuid, text, timestamp, index, uniqueIndex } from "drizzle-orm/pg-core";
+import { companies } from "./companies.js";
+import { issues } from "./issues.js";
+import { documents } from "./documents.js";
+
+export const issueDocuments = pgTable(
+  "issue_documents",
+  {
+    id: uuid("id").primaryKey().defaultRandom(),
+    companyId: uuid("company_id").notNull().references(() => companies.id),
+    issueId: uuid("issue_id").notNull().references(() => issues.id, { onDelete: "cascade" }),
+    documentId: uuid("document_id").notNull().references(() => documents.id, { onDelete: "cascade" }),
+    key: text("key").notNull(),
+    createdAt: timestamp("created_at", { withTimezone: true }).notNull().defaultNow(),
+    updatedAt: timestamp("updated_at", { withTimezone: true }).notNull().defaultNow(),
+  },
+  (table) => ({
+    companyIssueKeyUq: uniqueIndex("issue_documents_company_issue_key_uq").on(
+      table.companyId,
+      table.issueId,
+      table.key,
+    ),
+    documentUq: uniqueIndex("issue_documents_document_uq").on(table.documentId),
+    companyIssueUpdatedIdx: index("issue_documents_company_issue_updated_idx").on(
+      table.companyId,
+      table.issueId,
+      table.updatedAt,
+    ),
+  }),
+);
--- a/packages/shared/src/index.ts
+++ b/packages/shared/src/index.ts
@@ -86,6 +86,11 @@ export type {
  Issue,
  IssueAssigneeAdapterOverrides,
  IssueComment,
+  IssueDocument,
+  IssueDocumentSummary,
+  DocumentRevision,
+  DocumentFormat,
+  LegacyPlanDocument,
  IssueAttachment,
  IssueLabel,
  Goal,
@@ -172,6 +177,9 @@ export {
  addIssueCommentSchema,
  linkIssueApprovalSchema,
  createIssueAttachmentMetadataSchema,
+  issueDocumentFormatSchema,
+  issueDocumentKeySchema,
+  upsertIssueDocumentSchema,
  type CreateIssue,
  type CreateIssueLabel,
  type UpdateIssue,
@@ -179,6 +187,8 @@ export {
  type AddIssueComment,
  type LinkIssueApproval,
  type CreateIssueAttachmentMetadata,
+  type IssueDocumentFormat,
+  type UpsertIssueDocument,
  createGoalSchema,
  updateGoalSchema,
  type CreateGoal,
--- a/packages/shared/src/types/index.ts
+++ b/packages/shared/src/types/index.ts
@@ -23,6 +23,11 @@ export type {
  Issue,
  IssueAssigneeAdapterOverrides,
  IssueComment,
+  IssueDocument,
+  IssueDocumentSummary,
+  DocumentRevision,
+  DocumentFormat,
+  LegacyPlanDocument,
  IssueAncestor,
  IssueAncestorProject,
  IssueAncestorGoal,
--- a/packages/shared/src/types/issue.ts
+++ b/packages/shared/src/types/issue.ts
@@ -50,6 +50,49 @@ export interface IssueAssigneeAdapterOverrides {
  useProjectWorkspace?: boolean;
 }

+export type DocumentFormat = "markdown";
+
+export interface IssueDocumentSummary {
+  id: string;
+  companyId: string;
+  issueId: string;
+  key: string;
+  title: string | null;
+  format: DocumentFormat;
+  latestRevisionId: string;
+  latestRevisionNumber: number;
+  createdByAgentId: string | null;
+  createdByUserId: string | null;
+  updatedByAgentId: string | null;
+  updatedByUserId: string | null;
+  createdAt: Date;
+  updatedAt: Date;
+}
+
+export interface IssueDocument extends IssueDocumentSummary {
+  body: string;
+}
+
+export interface DocumentRevision {
+  id: string;
+  companyId: string;
+  documentId: string;
+  issueId: string;
+  key: string;
+  revisionNumber: number;
+  body: string;
+  changeSummary: string | null;
+  createdByAgentId: string | null;
+  createdByUserId: string | null;
+  createdAt: Date;
+}
+
+export interface LegacyPlanDocument {
+  key: "plan";
+  body: string;
+  source: "issue_description";
+}
+
 export interface Issue {
  id: string;
  companyId: string;
@@ -81,6 +124,9 @@ export interface Issue {
  hiddenAt: Date | null;
  labelIds?: string[];
  labels?: IssueLabel[];
+  planDocument?: IssueDocument | null;
+  documentSummaries?: IssueDocumentSummary[];
+  legacyPlanDocument?: LegacyPlanDocument | null;
  project?: Project | null;
  goal?: Goal | null;
  mentionedProjects?: Project[];
--- a/packages/shared/src/validators/index.ts
+++ b/packages/shared/src/validators/index.ts
@@ -66,6 +66,9 @@ export {
  addIssueCommentSchema,
  linkIssueApprovalSchema,
  createIssueAttachmentMetadataSchema,
+  issueDocumentFormatSchema,
+  issueDocumentKeySchema,
+  upsertIssueDocumentSchema,
  type CreateIssue,
  type CreateIssueLabel,
  type UpdateIssue,
@@ -74,6 +77,8 @@ export {
  type AddIssueComment,
  type LinkIssueApproval,
  type CreateIssueAttachmentMetadata,
+  type IssueDocumentFormat,
+  type UpsertIssueDocument,
 } from "./issue.js";

 export {
--- a/packages/shared/src/validators/issue.ts
+++ b/packages/shared/src/validators/issue.ts
@@ -87,3 +87,25 @@ export const createIssueAttachmentMetadataSchema = z.object({
 });

 export type CreateIssueAttachmentMetadata = z.infer<typeof createIssueAttachmentMetadataSchema>;
+
+export const ISSUE_DOCUMENT_FORMATS = ["markdown"] as const;
+
+export const issueDocumentFormatSchema = z.enum(ISSUE_DOCUMENT_FORMATS);
+
+export const issueDocumentKeySchema = z
+  .string()
+  .trim()
+  .min(1)
+  .max(64)
+  .regex(/^[a-z0-9][a-z0-9_-]*$/, "Document key must be lowercase letters, numbers, _ or -");
+
+export const upsertIssueDocumentSchema = z.object({
+  title: z.string().trim().max(200).nullable().optional(),
+  format: issueDocumentFormatSchema,
+  body: z.string(),
+  changeSummary: z.string().trim().max(500).nullable().optional(),
+  baseRevisionId: z.string().uuid().nullable().optional(),
+});
+
+export type IssueDocumentFormat = z.infer<typeof issueDocumentFormatSchema>;
+export type UpsertIssueDocument = z.infer<typeof upsertIssueDocumentSchema>;
--- a/server/src/tests/documents.test.ts
+++ b/server/src/tests/documents.test.ts
@@ -0,0 +1,29 @@
+import { describe, expect, it } from "vitest";
+import { extractLegacyPlanBody } from "../services/documents.js";
+
+describe("extractLegacyPlanBody", () => {
+  it("returns null when no plan block exists", () => {
+    expect(extractLegacyPlanBody("hello world")).toBeNull();
+  });
+
+  it("extracts plan body from legacy issue descriptions", () => {
+    expect(
+      extractLegacyPlanBody(`
+intro
+
+<plan>
+
+# Plan
+
+- one
+- two
+
+</plan>
+      `),
+    ).toBe("# Plan\n\n- one\n- two");
+  });
+
+  it("ignores empty plan blocks", () => {
+    expect(extractLegacyPlanBody("<plan>   </plan>")).toBeNull();
+  });
+});
--- a/server/src/attachment-types.ts
+++ b/server/src/attachment-types.ts
@@ -21,6 +21,12 @@ export const DEFAULT_ALLOWED_TYPES: readonly string[] = [
  "image/jpg",
  "image/webp",
  "image/gif",
+  "application/pdf",
+  "text/markdown",
+  "text/plain",
+  "application/json",
+  "text/csv",
+  "text/html",
 ];

 /**
--- a/server/src/routes/issues.ts
+++ b/server/src/routes/issues.ts
@@ -8,6 +8,8 @@ import {
  checkoutIssueSchema,
  createIssueSchema,
  linkIssueApprovalSchema,
+  issueDocumentKeySchema,
+  upsertIssueDocumentSchema,
  updateIssueSchema,
 } from "@paperclipai/shared";
 import type { StorageService } from "../storage/types.js";
@@ -19,6 +21,7 @@ import {
  heartbeatService,
  issueApprovalService,
  issueService,
+  documentService,
  logActivity,
  projectService,
 } from "../services/index.js";
@@ -37,6 +40,7 @@ export function issueRoutes(db: Db, storage: StorageService) {
  const projectsSvc = projectService(db);
  const goalsSvc = goalService(db);
  const issueApprovalsSvc = issueApprovalService(db);
+  const documentsSvc = documentService(db);
  const upload = multer({
    storage: multer.memoryStorage(),
    limits: { fileSize: MAX_ATTACHMENT_BYTES, files: 1 },
@@ -291,7 +295,7 @@ export function issueRoutes(db: Db, storage: StorageService) {
      return;
    }
    assertCompanyAccess(req, issue.companyId);
-    const [ancestors, project, goal, mentionedProjectIds] = await Promise.all([
+    const [ancestors, project, goal, mentionedProjectIds, documentPayload] = await Promise.all([
      svc.getAncestors(issue.id),
      issue.projectId ? projectsSvc.getById(issue.projectId) : null,
      issue.goalId
@@ -300,6 +304,7 @@ export function issueRoutes(db: Db, storage: StorageService) {
          ? goalsSvc.getDefaultCompanyGoal(issue.companyId)
          : null,
      svc.findMentionedProjectIds(issue.id),
+      documentsSvc.getIssueDocumentPayload(issue),
    ]);
    const mentionedProjects = mentionedProjectIds.length > 0
      ? await projectsSvc.listByIds(issue.companyId, mentionedProjectIds)
@@ -308,12 +313,153 @@ export function issueRoutes(db: Db, storage: StorageService) {
      ...issue,
      goalId: goal?.id ?? issue.goalId,
      ancestors,
+      ...documentPayload,
      project: project ?? null,
      goal: goal ?? null,
      mentionedProjects,
    });
  });

+  router.get("/issues/:id/documents", async (req, res) => {
+    const id = req.params.id as string;
+    const issue = await svc.getById(id);
+    if (!issue) {
+      res.status(404).json({ error: "Issue not found" });
+      return;
+    }
+    assertCompanyAccess(req, issue.companyId);
+    const docs = await documentsSvc.listIssueDocuments(issue.id);
+    res.json(docs);
+  });
+
+  router.get("/issues/:id/documents/:key", async (req, res) => {
+    const id = req.params.id as string;
+    const issue = await svc.getById(id);
+    if (!issue) {
+      res.status(404).json({ error: "Issue not found" });
+      return;
+    }
+    assertCompanyAccess(req, issue.companyId);
+    const keyParsed = issueDocumentKeySchema.safeParse(String(req.params.key ?? "").trim().toLowerCase());
+    if (!keyParsed.success) {
+      res.status(400).json({ error: "Invalid document key", details: keyParsed.error.issues });
+      return;
+    }
+    const doc = await documentsSvc.getIssueDocumentByKey(issue.id, keyParsed.data);
+    if (!doc) {
+      res.status(404).json({ error: "Document not found" });
+      return;
+    }
+    res.json(doc);
+  });
+
+  router.put("/issues/:id/documents/:key", validate(upsertIssueDocumentSchema), async (req, res) => {
+    const id = req.params.id as string;
+    const issue = await svc.getById(id);
+    if (!issue) {
+      res.status(404).json({ error: "Issue not found" });
+      return;
+    }
+    assertCompanyAccess(req, issue.companyId);
+    const keyParsed = issueDocumentKeySchema.safeParse(String(req.params.key ?? "").trim().toLowerCase());
+    if (!keyParsed.success) {
+      res.status(400).json({ error: "Invalid document key", details: keyParsed.error.issues });
+      return;
+    }
+
+    const actor = getActorInfo(req);
+    const before = await documentsSvc.getIssueDocumentByKey(issue.id, keyParsed.data);
+    const doc = await documentsSvc.upsertIssueDocument({
+      issueId: issue.id,
+      key: keyParsed.data,
+      title: req.body.title ?? null,
+      format: req.body.format,
+      body: req.body.body,
+      changeSummary: req.body.changeSummary ?? null,
+      baseRevisionId: req.body.baseRevisionId ?? null,
+      createdByAgentId: actor.agentId ?? null,
+      createdByUserId: actor.actorType === "user" ? actor.actorId : null,
+    });
+
+    await logActivity(db, {
+      companyId: issue.companyId,
+      actorType: actor.actorType,
+      actorId: actor.actorId,
+      agentId: actor.agentId,
+      runId: actor.runId,
+      action: before ? "issue.document_updated" : "issue.document_created",
+      entityType: "issue",
+      entityId: issue.id,
+      details: {
+        key: doc.key,
+        documentId: doc.id,
+        title: doc.title,
+        format: doc.format,
+        revisionNumber: doc.latestRevisionNumber,
+      },
+    });
+
+    res.status(before ? 200 : 201).json(doc);
+  });
+
+  router.get("/issues/:id/documents/:key/revisions", async (req, res) => {
+    const id = req.params.id as string;
+    const issue = await svc.getById(id);
+    if (!issue) {
+      res.status(404).json({ error: "Issue not found" });
+      return;
+    }
+    assertCompanyAccess(req, issue.companyId);
+    const keyParsed = issueDocumentKeySchema.safeParse(String(req.params.key ?? "").trim().toLowerCase());
+    if (!keyParsed.success) {
+      res.status(400).json({ error: "Invalid document key", details: keyParsed.error.issues });
+      return;
+    }
+    const revisions = await documentsSvc.listIssueDocumentRevisions(issue.id, keyParsed.data);
+    res.json(revisions);
+  });
+
+  router.delete("/issues/:id/documents/:key", async (req, res) => {
+    const id = req.params.id as string;
+    const issue = await svc.getById(id);
+    if (!issue) {
+      res.status(404).json({ error: "Issue not found" });
+      return;
+    }
+    assertCompanyAccess(req, issue.companyId);
+    if (req.actor.type !== "board") {
+      res.status(403).json({ error: "Board authentication required" });
+      return;
+    }
+    const keyParsed = issueDocumentKeySchema.safeParse(String(req.params.key ?? "").trim().toLowerCase());
+    if (!keyParsed.success) {
+      res.status(400).json({ error: "Invalid document key", details: keyParsed.error.issues });
+      return;
+    }
+    const removed = await documentsSvc.deleteIssueDocument(issue.id, keyParsed.data);
+    if (!removed) {
+      res.status(404).json({ error: "Document not found" });
+      return;
+    }
+    const actor = getActorInfo(req);
+    await logActivity(db, {
+      companyId: issue.companyId,
+      actorType: actor.actorType,
+      actorId: actor.actorId,
+      agentId: actor.agentId,
+      runId: actor.runId,
+      action: "issue.document_deleted",
+      entityType: "issue",
+      entityId: issue.id,
+      details: {
+        key: removed.key,
+        documentId: removed.id,
+        title: removed.title,
+      },
+    });
+    res.json({ ok: true });
+  });
+
  router.post("/issues/:id/read", async (req, res) => {
    const id = req.params.id as string;
    const issue = await svc.getById(id);
--- a/server/src/services/documents.ts
+++ b/server/src/services/documents.ts
@@ -0,0 +1,427 @@
+import { and, asc, desc, eq } from "drizzle-orm";
+import type { Db } from "@paperclipai/db";
+import { documentRevisions, documents, issueDocuments, issues } from "@paperclipai/db";
+import { issueDocumentKeySchema } from "@paperclipai/shared";
+import { conflict, notFound, unprocessable } from "../errors.js";
+
+function normalizeDocumentKey(key: string) {
+  const normalized = key.trim().toLowerCase();
+  const parsed = issueDocumentKeySchema.safeParse(normalized);
+  if (!parsed.success) {
+    throw unprocessable("Invalid document key", parsed.error.issues);
+  }
+  return parsed.data;
+}
+
+function isUniqueViolation(error: unknown): boolean {
+  return !!error && typeof error === "object" && "code" in error && (error as { code?: string }).code === "23505";
+}
+
+export function extractLegacyPlanBody(description: string | null | undefined) {
+  if (!description) return null;
+  const match = /<plan>\s*([\s\S]*?)\s*<\/plan>/i.exec(description);
+  if (!match) return null;
+  const body = match[1]?.trim();
+  return body ? body : null;
+}
+
+function mapIssueDocumentRow(
+  row: {
+    id: string;
+    companyId: string;
+    issueId: string;
+    key: string;
+    title: string | null;
+    format: string;
+    latestBody: string;
+    latestRevisionId: string | null;
+    latestRevisionNumber: number;
+    createdByAgentId: string | null;
+    createdByUserId: string | null;
+    updatedByAgentId: string | null;
+    updatedByUserId: string | null;
+    createdAt: Date;
+    updatedAt: Date;
+  },
+  includeBody: boolean,
+) {
+  return {
+    id: row.id,
+    companyId: row.companyId,
+    issueId: row.issueId,
+    key: row.key,
+    title: row.title,
+    format: row.format,
+    ...(includeBody ? { body: row.latestBody } : {}),
+    latestRevisionId: row.latestRevisionId ?? "",
+    latestRevisionNumber: row.latestRevisionNumber,
+    createdByAgentId: row.createdByAgentId,
+    createdByUserId: row.createdByUserId,
+    updatedByAgentId: row.updatedByAgentId,
+    updatedByUserId: row.updatedByUserId,
+    createdAt: row.createdAt,
+    updatedAt: row.updatedAt,
+  };
+}
+
+export function documentService(db: Db) {
+  return {
+    getIssueDocumentPayload: async (issue: { id: string; description: string | null }) => {
+      const [planDocument, documentSummaries] = await Promise.all([
+        db
+          .select({
+            id: documents.id,
+            companyId: documents.companyId,
+            issueId: issueDocuments.issueId,
+            key: issueDocuments.key,
+            title: documents.title,
+            format: documents.format,
+            latestBody: documents.latestBody,
+            latestRevisionId: documents.latestRevisionId,
+            latestRevisionNumber: documents.latestRevisionNumber,
+            createdByAgentId: documents.createdByAgentId,
+            createdByUserId: documents.createdByUserId,
+            updatedByAgentId: documents.updatedByAgentId,
+            updatedByUserId: documents.updatedByUserId,
+            createdAt: documents.createdAt,
+            updatedAt: documents.updatedAt,
+          })
+          .from(issueDocuments)
+          .innerJoin(documents, eq(issueDocuments.documentId, documents.id))
+          .where(and(eq(issueDocuments.issueId, issue.id), eq(issueDocuments.key, "plan")))
+          .then((rows) => rows[0] ?? null),
+        db
+          .select({
+            id: documents.id,
+            companyId: documents.companyId,
+            issueId: issueDocuments.issueId,
+            key: issueDocuments.key,
+            title: documents.title,
+            format: documents.format,
+            latestBody: documents.latestBody,
+            latestRevisionId: documents.latestRevisionId,
+            latestRevisionNumber: documents.latestRevisionNumber,
+            createdByAgentId: documents.createdByAgentId,
+            createdByUserId: documents.createdByUserId,
+            updatedByAgentId: documents.updatedByAgentId,
+            updatedByUserId: documents.updatedByUserId,
+            createdAt: documents.createdAt,
+            updatedAt: documents.updatedAt,
+          })
+          .from(issueDocuments)
+          .innerJoin(documents, eq(issueDocuments.documentId, documents.id))
+          .where(eq(issueDocuments.issueId, issue.id))
+          .orderBy(asc(issueDocuments.key), desc(documents.updatedAt)),
+      ]);
+
+      const legacyPlanBody = planDocument ? null : extractLegacyPlanBody(issue.description);
+
+      return {
+        planDocument: planDocument ? mapIssueDocumentRow(planDocument, true) : null,
+        documentSummaries: documentSummaries.map((row) => mapIssueDocumentRow(row, false)),
+        legacyPlanDocument: legacyPlanBody
+          ? {
+              key: "plan" as const,
+              body: legacyPlanBody,
+              source: "issue_description" as const,
+            }
+          : null,
+      };
+    },
+
+    listIssueDocuments: async (issueId: string) => {
+      const rows = await db
+        .select({
+          id: documents.id,
+          companyId: documents.companyId,
+          issueId: issueDocuments.issueId,
+          key: issueDocuments.key,
+          title: documents.title,
+          format: documents.format,
+          latestBody: documents.latestBody,
+          latestRevisionId: documents.latestRevisionId,
+          latestRevisionNumber: documents.latestRevisionNumber,
+          createdByAgentId: documents.createdByAgentId,
+          createdByUserId: documents.createdByUserId,
+          updatedByAgentId: documents.updatedByAgentId,
+          updatedByUserId: documents.updatedByUserId,
+          createdAt: documents.createdAt,
+          updatedAt: documents.updatedAt,
+        })
+        .from(issueDocuments)
+        .innerJoin(documents, eq(issueDocuments.documentId, documents.id))
+        .where(eq(issueDocuments.issueId, issueId))
+        .orderBy(asc(issueDocuments.key), desc(documents.updatedAt));
+      return rows.map((row) => mapIssueDocumentRow(row, true));
+    },
+
+    getIssueDocumentByKey: async (issueId: string, rawKey: string) => {
+      const key = normalizeDocumentKey(rawKey);
+      const row = await db
+        .select({
+          id: documents.id,
+          companyId: documents.companyId,
+          issueId: issueDocuments.issueId,
+          key: issueDocuments.key,
+          title: documents.title,
+          format: documents.format,
+          latestBody: documents.latestBody,
+          latestRevisionId: documents.latestRevisionId,
+          latestRevisionNumber: documents.latestRevisionNumber,
+          createdByAgentId: documents.createdByAgentId,
+          createdByUserId: documents.createdByUserId,
+          updatedByAgentId: documents.updatedByAgentId,
+          updatedByUserId: documents.updatedByUserId,
+          createdAt: documents.createdAt,
+          updatedAt: documents.updatedAt,
+        })
+        .from(issueDocuments)
+        .innerJoin(documents, eq(issueDocuments.documentId, documents.id))
+        .where(and(eq(issueDocuments.issueId, issueId), eq(issueDocuments.key, key)))
+        .then((rows) => rows[0] ?? null);
+      return row ? mapIssueDocumentRow(row, true) : null;
+    },
+
+    listIssueDocumentRevisions: async (issueId: string, rawKey: string) => {
+      const key = normalizeDocumentKey(rawKey);
+      return db
+        .select({
+          id: documentRevisions.id,
+          companyId: documentRevisions.companyId,
+          documentId: documentRevisions.documentId,
+          issueId: issueDocuments.issueId,
+          key: issueDocuments.key,
+          revisionNumber: documentRevisions.revisionNumber,
+          body: documentRevisions.body,
+          changeSummary: documentRevisions.changeSummary,
+          createdByAgentId: documentRevisions.createdByAgentId,
+          createdByUserId: documentRevisions.createdByUserId,
+          createdAt: documentRevisions.createdAt,
+        })
+        .from(issueDocuments)
+        .innerJoin(documents, eq(issueDocuments.documentId, documents.id))
+        .innerJoin(documentRevisions, eq(documentRevisions.documentId, documents.id))
+        .where(and(eq(issueDocuments.issueId, issueId), eq(issueDocuments.key, key)))
+        .orderBy(desc(documentRevisions.revisionNumber));
+    },
+
+    upsertIssueDocument: async (input: {
+      issueId: string;
+      key: string;
+      title?: string | null;
+      format: string;
+      body: string;
+      changeSummary?: string | null;
+      baseRevisionId?: string | null;
+      createdByAgentId?: string | null;
+      createdByUserId?: string | null;
+    }) => {
+      const key = normalizeDocumentKey(input.key);
+      const issue = await db
+        .select({ id: issues.id, companyId: issues.companyId })
+        .from(issues)
+        .where(eq(issues.id, input.issueId))
+        .then((rows) => rows[0] ?? null);
+      if (!issue) throw notFound("Issue not found");
+
+      try {
+        return await db.transaction(async (tx) => {
+          const now = new Date();
+          const existing = await tx
+            .select({
+              id: documents.id,
+              companyId: documents.companyId,
+              issueId: issueDocuments.issueId,
+              key: issueDocuments.key,
+              title: documents.title,
+              format: documents.format,
+              latestBody: documents.latestBody,
+              latestRevisionId: documents.latestRevisionId,
+              latestRevisionNumber: documents.latestRevisionNumber,
+              createdByAgentId: documents.createdByAgentId,
+              createdByUserId: documents.createdByUserId,
+              updatedByAgentId: documents.updatedByAgentId,
+              updatedByUserId: documents.updatedByUserId,
+              createdAt: documents.createdAt,
+              updatedAt: documents.updatedAt,
+            })
+            .from(issueDocuments)
+            .innerJoin(documents, eq(issueDocuments.documentId, documents.id))
+            .where(and(eq(issueDocuments.issueId, issue.id), eq(issueDocuments.key, key)))
+            .then((rows) => rows[0] ?? null);
+
+          if (existing) {
+            if (!input.baseRevisionId) {
+              throw conflict("Document update requires baseRevisionId", {
+                currentRevisionId: existing.latestRevisionId,
+              });
+            }
+            if (input.baseRevisionId !== existing.latestRevisionId) {
+              throw conflict("Document was updated by someone else", {
+                currentRevisionId: existing.latestRevisionId,
+              });
+            }
+
+            const nextRevisionNumber = existing.latestRevisionNumber + 1;
+            const [revision] = await tx
+              .insert(documentRevisions)
+              .values({
+                companyId: issue.companyId,
+                documentId: existing.id,
+                revisionNumber: nextRevisionNumber,
+                body: input.body,
+                changeSummary: input.changeSummary ?? null,
+                createdByAgentId: input.createdByAgentId ?? null,
+                createdByUserId: input.createdByUserId ?? null,
+                createdAt: now,
+              })
+              .returning();
+
+            await tx
+              .update(documents)
+              .set({
+                title: input.title ?? null,
+                format: input.format,
+                latestBody: input.body,
+                latestRevisionId: revision.id,
+                latestRevisionNumber: nextRevisionNumber,
+                updatedByAgentId: input.createdByAgentId ?? null,
+                updatedByUserId: input.createdByUserId ?? null,
+                updatedAt: now,
+              })
+              .where(eq(documents.id, existing.id));
+
+            await tx
+              .update(issueDocuments)
+              .set({ updatedAt: now })
+              .where(eq(issueDocuments.documentId, existing.id));
+
+            return {
+              ...existing,
+              title: input.title ?? null,
+              format: input.format,
+              body: input.body,
+              latestRevisionId: revision.id,
+              latestRevisionNumber: nextRevisionNumber,
+              updatedByAgentId: input.createdByAgentId ?? null,
+              updatedByUserId: input.createdByUserId ?? null,
+              updatedAt: now,
+            };
+          }
+
+          if (input.baseRevisionId) {
+            throw conflict("Document does not exist yet", { key });
+          }
+
+          const [document] = await tx
+            .insert(documents)
+            .values({
+              companyId: issue.companyId,
+              title: input.title ?? null,
+              format: input.format,
+              latestBody: input.body,
+              latestRevisionId: null,
+              latestRevisionNumber: 1,
+              createdByAgentId: input.createdByAgentId ?? null,
+              createdByUserId: input.createdByUserId ?? null,
+              updatedByAgentId: input.createdByAgentId ?? null,
+              updatedByUserId: input.createdByUserId ?? null,
+              createdAt: now,
+              updatedAt: now,
+            })
+            .returning();
+
+          const [revision] = await tx
+            .insert(documentRevisions)
+            .values({
+              companyId: issue.companyId,
+              documentId: document.id,
+              revisionNumber: 1,
+              body: input.body,
+              changeSummary: input.changeSummary ?? null,
+              createdByAgentId: input.createdByAgentId ?? null,
+              createdByUserId: input.createdByUserId ?? null,
+              createdAt: now,
+            })
+            .returning();
+
+          await tx
+            .update(documents)
+            .set({ latestRevisionId: revision.id })
+            .where(eq(documents.id, document.id));
+
+          await tx.insert(issueDocuments).values({
+            companyId: issue.companyId,
+            issueId: issue.id,
+            documentId: document.id,
+            key,
+            createdAt: now,
+            updatedAt: now,
+          });
+
+          return {
+            id: document.id,
+            companyId: issue.companyId,
+            issueId: issue.id,
+            key,
+            title: document.title,
+            format: document.format,
+            body: document.latestBody,
+            latestRevisionId: revision.id,
+            latestRevisionNumber: 1,
+            createdByAgentId: document.createdByAgentId,
+            createdByUserId: document.createdByUserId,
+            updatedByAgentId: document.updatedByAgentId,
+            updatedByUserId: document.updatedByUserId,
+            createdAt: document.createdAt,
+            updatedAt: document.updatedAt,
+          };
+        });
+      } catch (error) {
+        if (isUniqueViolation(error)) {
+          throw conflict("Document key already exists on this issue", { key });
+        }
+        throw error;
+      }
+    },
+
+    deleteIssueDocument: async (issueId: string, rawKey: string) => {
+      const key = normalizeDocumentKey(rawKey);
+      return db.transaction(async (tx) => {
+        const existing = await tx
+          .select({
+            id: documents.id,
+            companyId: documents.companyId,
+            issueId: issueDocuments.issueId,
+            key: issueDocuments.key,
+            title: documents.title,
+            format: documents.format,
+            latestBody: documents.latestBody,
+            latestRevisionId: documents.latestRevisionId,
+            latestRevisionNumber: documents.latestRevisionNumber,
+            createdByAgentId: documents.createdByAgentId,
+            createdByUserId: documents.createdByUserId,
+            updatedByAgentId: documents.updatedByAgentId,
+            updatedByUserId: documents.updatedByUserId,
+            createdAt: documents.createdAt,
+            updatedAt: documents.updatedAt,
+          })
+          .from(issueDocuments)
+          .innerJoin(documents, eq(issueDocuments.documentId, documents.id))
+          .where(and(eq(issueDocuments.issueId, issueId), eq(issueDocuments.key, key)))
+          .then((rows) => rows[0] ?? null);
+
+        if (!existing) return null;
+
+        await tx.delete(issueDocuments).where(eq(issueDocuments.documentId, existing.id));
+        await tx.delete(documents).where(eq(documents.id, existing.id));
+
+        return {
+          ...existing,
+          body: existing.latestBody,
+          latestRevisionId: existing.latestRevisionId ?? "",
+        };
+      });
+    },
+  };
+}
--- a/server/src/services/index.ts
+++ b/server/src/services/index.ts
@@ -1,6 +1,7 @@
 export { companyService } from "./companies.js";
 export { agentService, deduplicateAgentName } from "./agents.js";
 export { assetService } from "./assets.js";
+export { documentService, extractLegacyPlanBody } from "./documents.js";
 export { projectService } from "./projects.js";
 export { issueService, type IssueFilters } from "./issues.js";
 export { issueApprovalService } from "./issue-approvals.js";
--- a/skills/paperclip/SKILL.md
+++ b/skills/paperclip/SKILL.md
@@ -168,31 +168,23 @@ Submitted CTO hire request and linked it for board review.

 ## Planning (Required when planning requested)

-If you're asked to make a plan, create that plan in your regular way (e.g. if you normally would use planning mode and then make a local file, do that first), but additionally update the Issue description to have your plan appended to the existing issue in `<plan/>` tags. You MUST keep the original Issue description exactly in tact. ONLY add/edit your plan. If you're asked for plan revisions, update your `<plan/>` with the revision. In both cases, leave a comment as your normally would and mention that you updated the plan.
+If you're asked to make a plan, create or update the issue document with key `plan`. Do not append plans into the issue description anymore. If you're asked for plan revisions, update that same `plan` document. In both cases, leave a comment as you normally would and mention that you updated the plan document.

 If you're asked to make a plan, _do not mark the issue as done_. Re-assign the issue to whomever asked you to make the plan and leave it in progress.

-Example:
+Recommended API flow:

-Original Issue Description:
-
-```
-pls show the costs in either token or dollars on the /issues/{id} page. Make a plan first.
+```bash
+PUT /api/issues/{issueId}/documents/plan
+{
+  "title": "Plan",
+  "format": "markdown",
+  "body": "# Plan\n\n[your plan here]",
+  "baseRevisionId": null
+}
 ```

-After:
-
-```
-pls show the costs in either token or dollars on the /issues/{id} page. Make a plan first.
-
-<plan>
-
-[your plan here]
-
-</plan>
-```
-
-\*make sure to have a newline after/before your <plan/> tags
+If `plan` already exists, fetch the current document first and send its latest `baseRevisionId` when you update it.

 ## Setting Agent Instructions Path

@@ -229,6 +221,10 @@ PATCH /api/agents/{agentId}/instructions-path
 | My assignments                        | `GET /api/companies/:companyId/issues?assigneeAgentId=:id&status=todo,in_progress,blocked` |
 | Checkout task                         | `POST /api/issues/:issueId/checkout`                                                       |
 | Get task + ancestors                  | `GET /api/issues/:issueId`                                                                 |
+| List issue documents                  | `GET /api/issues/:issueId/documents`                                                       |
+| Get issue document                    | `GET /api/issues/:issueId/documents/:key`                                                  |
+| Create/update issue document          | `PUT /api/issues/:issueId/documents/:key`                                                  |
+| Get issue document revisions          | `GET /api/issues/:issueId/documents/:key/revisions`                                        |
 | Get comments                          | `GET /api/issues/:issueId/comments`                                                        |
 | Get specific comment                  | `GET /api/issues/:issueId/comments/:commentId`                                             |
 | Update task                           | `PATCH /api/issues/:issueId` (optional `comment` field)                                    |
--- a/ui/src/api/client.ts
+++ b/ui/src/api/client.ts
@@ -41,6 +41,8 @@ export const api = {
    request<T>(path, { method: "POST", body: JSON.stringify(body) }),
  postForm: <T>(path: string, body: FormData) =>
    request<T>(path, { method: "POST", body }),
+  put: <T>(path: string, body: unknown) =>
+    request<T>(path, { method: "PUT", body: JSON.stringify(body) }),
  patch: <T>(path: string, body: unknown) =>
    request<T>(path, { method: "PATCH", body: JSON.stringify(body) }),
  delete: <T>(path: string) => request<T>(path, { method: "DELETE" }),
--- a/ui/src/api/issues.ts
+++ b/ui/src/api/issues.ts
@@ -1,4 +1,13 @@
-import type { Approval, Issue, IssueAttachment, IssueComment, IssueLabel } from "@paperclipai/shared";
+import type {
+  Approval,
+  DocumentRevision,
+  Issue,
+  IssueAttachment,
+  IssueComment,
+  IssueDocument,
+  IssueLabel,
+  UpsertIssueDocument,
+} from "@paperclipai/shared";
 import { api } from "./client";

 export const issuesApi = {
@@ -53,6 +62,14 @@ export const issuesApi = {
        ...(interrupt === undefined ? {} : { interrupt }),
      },
    ),
+  listDocuments: (id: string) => api.get<IssueDocument[]>(`/issues/${id}/documents`),
+  getDocument: (id: string, key: string) => api.get<IssueDocument>(`/issues/${id}/documents/${encodeURIComponent(key)}`),
+  upsertDocument: (id: string, key: string, data: UpsertIssueDocument) =>
+    api.put<IssueDocument>(`/issues/${id}/documents/${encodeURIComponent(key)}`, data),
+  listDocumentRevisions: (id: string, key: string) =>
+    api.get<DocumentRevision[]>(`/issues/${id}/documents/${encodeURIComponent(key)}/revisions`),
+  deleteDocument: (id: string, key: string) =>
+    api.delete<{ ok: true }>(`/issues/${id}/documents/${encodeURIComponent(key)}`),
  listAttachments: (id: string) => api.get<IssueAttachment[]>(`/issues/${id}/attachments`),
  uploadAttachment: (
    companyId: string,
--- a/ui/src/components/ActivityRow.tsx
+++ b/ui/src/components/ActivityRow.tsx
@@ -12,6 +12,9 @@ const ACTION_VERBS: Record<string, string> = {
  "issue.comment_added": "commented on",
  "issue.attachment_added": "attached file to",
  "issue.attachment_removed": "removed attachment from",
+  "issue.document_created": "created document for",
+  "issue.document_updated": "updated document on",
+  "issue.document_deleted": "deleted document from",
  "issue.commented": "commented on",
  "issue.deleted": "deleted",
  "agent.created": "created",
--- a/ui/src/components/InlineEditor.tsx
+++ b/ui/src/components/InlineEditor.tsx
@@ -1,12 +1,11 @@
 import { useState, useRef, useEffect, useCallback } from "react";
 import { cn } from "../lib/utils";
-import { Button } from "@/components/ui/button";
-import { MarkdownBody } from "./MarkdownBody";
-import { MarkdownEditor, type MentionOption } from "./MarkdownEditor";
+import { MarkdownEditor, type MarkdownEditorRef, type MentionOption } from "./MarkdownEditor";
+import { useAutosaveIndicator } from "../hooks/useAutosaveIndicator";

 interface InlineEditorProps {
  value: string;
-  onSave: (value: string) => void;
+  onSave: (value: string) => void | Promise<unknown>;
  as?: "h1" | "h2" | "p" | "span";
  className?: string;
  placeholder?: string;
@@ -17,6 +16,8 @@ interface InlineEditorProps {

 /** Shared padding so display and edit modes occupy the exact same box. */
 const pad = "px-1 -mx-1";
+const markdownPad = "px-1";
+const AUTOSAVE_DEBOUNCE_MS = 900;

 export function InlineEditor({
  value,
@@ -29,12 +30,30 @@ export function InlineEditor({
  mentions,
 }: InlineEditorProps) {
  const [editing, setEditing] = useState(false);
+  const [multilineFocused, setMultilineFocused] = useState(false);
  const [draft, setDraft] = useState(value);
  const inputRef = useRef<HTMLTextAreaElement>(null);
+  const markdownRef = useRef<MarkdownEditorRef>(null);
+  const autosaveDebounceRef = useRef<ReturnType<typeof setTimeout> | null>(null);
+  const {
+    state: autosaveState,
+    markDirty,
+    reset,
+    runSave,
+  } = useAutosaveIndicator();

  useEffect(() => {
+    if (multiline && multilineFocused) return;
    setDraft(value);
-  }, [value]);
+  }, [value, multiline, multilineFocused]);
+
+  useEffect(() => {
+    return () => {
+      if (autosaveDebounceRef.current) {
+        clearTimeout(autosaveDebounceRef.current);
+      }
+    };
+  }, []);

  const autoSize = useCallback((el: HTMLTextAreaElement | null) => {
    if (!el) return;
@@ -52,59 +71,141 @@ export function InlineEditor({
    }
  }, [editing, autoSize]);

-  function commit() {
-    const trimmed = draft.trim();
+  useEffect(() => {
+    if (!editing || !multiline) return;
+    const frame = requestAnimationFrame(() => {
+      markdownRef.current?.focus();
+    });
+    return () => cancelAnimationFrame(frame);
+  }, [editing, multiline]);
+
+  const commit = useCallback(async (nextValue = draft) => {
+    const trimmed = nextValue.trim();
    if (trimmed && trimmed !== value) {
-      onSave(trimmed);
+      await Promise.resolve(onSave(trimmed));
    } else {
      setDraft(value);
    }
+    if (!multiline) {
      setEditing(false);
    }
+  }, [draft, multiline, onSave, value]);

  function handleKeyDown(e: React.KeyboardEvent) {
    if (e.key === "Enter" && !multiline) {
      e.preventDefault();
-      commit();
+      void commit();
    }
    if (e.key === "Escape") {
+      if (autosaveDebounceRef.current) {
+        clearTimeout(autosaveDebounceRef.current);
+      }
+      reset();
      setDraft(value);
+      if (multiline) {
+        setMultilineFocused(false);
+        if (document.activeElement instanceof HTMLElement) {
+          document.activeElement.blur();
+        }
+      } else {
        setEditing(false);
      }
    }
+  }
+
+  useEffect(() => {
+    if (!multiline) return;
+    if (!multilineFocused) return;
+    const trimmed = draft.trim();
+    if (!trimmed || trimmed === value) {
+      if (autosaveState !== "saved") {
+        reset();
+      }
+      return;
+    }
+    markDirty();
+    if (autosaveDebounceRef.current) {
+      clearTimeout(autosaveDebounceRef.current);
+    }
+    autosaveDebounceRef.current = setTimeout(() => {
+      void runSave(() => commit(trimmed));
+    }, AUTOSAVE_DEBOUNCE_MS);
+
+    return () => {
+      if (autosaveDebounceRef.current) {
+        clearTimeout(autosaveDebounceRef.current);
+      }
+    };
+  }, [autosaveState, commit, draft, markDirty, multiline, multilineFocused, reset, runSave, value]);

-  if (editing) {
  if (multiline) {
    return (
-        <div className={cn("space-y-2", pad)}>
+      <div
+        className={cn(
+          markdownPad,
+          "rounded transition-colors",
+          multilineFocused ? "bg-transparent" : "hover:bg-accent/20",
+        )}
+        onFocusCapture={() => setMultilineFocused(true)}
+        onBlurCapture={(event) => {
+          if (event.currentTarget.contains(event.relatedTarget as Node | null)) return;
+          if (autosaveDebounceRef.current) {
+            clearTimeout(autosaveDebounceRef.current);
+          }
+          setMultilineFocused(false);
+          const trimmed = draft.trim();
+          if (!trimmed || trimmed === value) {
+            reset();
+            void commit();
+            return;
+          }
+          void runSave(() => commit());
+        }}
+        onKeyDown={handleKeyDown}
+      >
        <MarkdownEditor
+          ref={markdownRef}
          value={draft}
          onChange={setDraft}
          placeholder={placeholder}
-            contentClassName={className}
+          bordered={false}
+          className="bg-transparent"
+          contentClassName={cn("paperclip-edit-in-place-content", className)}
          imageUploadHandler={imageUploadHandler}
          mentions={mentions}
-            onSubmit={commit}
-          />
-          <div className="flex items-center justify-end gap-2">
-            <Button
-              variant="outline"
-              size="sm"
-              onClick={() => {
-                setDraft(value);
-                setEditing(false);
+          onSubmit={() => {
+            const trimmed = draft.trim();
+            if (!trimmed || trimmed === value) {
+              reset();
+              void commit();
+              return;
+            }
+            void runSave(() => commit());
          }}
+        />
+        <div className="flex min-h-4 items-center justify-end pr-1">
+          <span
+            className={cn(
+              "text-[11px] transition-opacity duration-150",
+              autosaveState === "error" ? "text-destructive" : "text-muted-foreground",
+              autosaveState === "idle" ? "opacity-0" : "opacity-100",
+            )}
          >
-              Cancel
-            </Button>
-            <Button size="sm" onClick={commit}>
-              Save
-            </Button>
+            {autosaveState === "saving"
+              ? "Autosaving..."
+              : autosaveState === "saved"
+                ? "Saved"
+                : autosaveState === "error"
+                  ? "Could not save"
+                  : "Idle"}
+          </span>
        </div>
      </div>
    );
  }

+  if (editing) {
+
    return (
      <textarea
        ref={inputRef}
@@ -114,7 +215,9 @@ export function InlineEditor({
          setDraft(e.target.value);
          autoSize(e.target);
        }}
-        onBlur={commit}
+        onBlur={() => {
+          void commit();
+        }}
        onKeyDown={handleKeyDown}
        className={cn(
          "w-full bg-transparent rounded outline-none resize-none overflow-hidden",
@@ -135,15 +238,11 @@ export function InlineEditor({
        "cursor-pointer rounded hover:bg-accent/50 transition-colors overflow-hidden",
        pad,
        !value && "text-muted-foreground italic",
-        className
+        className,
      )}
      onClick={() => setEditing(true)}
    >
-      {value && multiline ? (
-        <MarkdownBody>{value}</MarkdownBody>
-      ) : (
-        value || placeholder
-      )}
+      {value || placeholder}
    </DisplayTag>
  );
 }
--- a/ui/src/components/IssueDocumentsSection.tsx
+++ b/ui/src/components/IssueDocumentsSection.tsx
@@ -0,0 +1,510 @@
+import { useCallback, useEffect, useMemo, useRef, useState } from "react";
+import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
+import type { Issue } from "@paperclipai/shared";
+import { issuesApi } from "../api/issues";
+import { useAutosaveIndicator } from "../hooks/useAutosaveIndicator";
+import { queryKeys } from "../lib/queryKeys";
+import { relativeTime } from "../lib/utils";
+import { MarkdownBody } from "./MarkdownBody";
+import { MarkdownEditor, type MentionOption } from "./MarkdownEditor";
+import { Button } from "@/components/ui/button";
+import { Input } from "@/components/ui/input";
+import {
+  DropdownMenu,
+  DropdownMenuContent,
+  DropdownMenuItem,
+  DropdownMenuSeparator,
+  DropdownMenuTrigger,
+} from "@/components/ui/dropdown-menu";
+import { FileText, MoreHorizontal, Plus, Trash2, X } from "lucide-react";
+
+type DraftState = {
+  key: string;
+  title: string;
+  body: string;
+  baseRevisionId: string | null;
+  isNew: boolean;
+};
+
+const DOCUMENT_AUTOSAVE_DEBOUNCE_MS = 900;
+
+function renderBody(body: string, className?: string) {
+  return <MarkdownBody className={className}>{body}</MarkdownBody>;
+}
+
+function isPlanKey(key: string) {
+  return key.trim().toLowerCase() === "plan";
+}
+
+export function IssueDocumentsSection({
+  issue,
+  canDeleteDocuments,
+  mentions,
+  imageUploadHandler,
+}: {
+  issue: Issue;
+  canDeleteDocuments: boolean;
+  mentions?: MentionOption[];
+  imageUploadHandler?: (file: File) => Promise<string>;
+}) {
+  const queryClient = useQueryClient();
+  const [confirmDeleteKey, setConfirmDeleteKey] = useState<string | null>(null);
+  const [error, setError] = useState<string | null>(null);
+  const [draft, setDraft] = useState<DraftState | null>(null);
+  const autosaveDebounceRef = useRef<ReturnType<typeof setTimeout> | null>(null);
+  const {
+    state: autosaveState,
+    markDirty,
+    reset,
+    runSave,
+  } = useAutosaveIndicator();
+
+  const { data: documents } = useQuery({
+    queryKey: queryKeys.issues.documents(issue.id),
+    queryFn: () => issuesApi.listDocuments(issue.id),
+  });
+
+  const invalidateIssueDocuments = () => {
+    queryClient.invalidateQueries({ queryKey: queryKeys.issues.detail(issue.id) });
+    queryClient.invalidateQueries({ queryKey: queryKeys.issues.documents(issue.id) });
+  };
+
+  const upsertDocument = useMutation({
+    mutationFn: async (nextDraft: DraftState) =>
+      issuesApi.upsertDocument(issue.id, nextDraft.key, {
+        title: isPlanKey(nextDraft.key) ? null : nextDraft.title.trim() || null,
+        format: "markdown",
+        body: nextDraft.body,
+        baseRevisionId: nextDraft.baseRevisionId,
+      }),
+  });
+
+  const deleteDocument = useMutation({
+    mutationFn: (key: string) => issuesApi.deleteDocument(issue.id, key),
+    onSuccess: () => {
+      setError(null);
+      setConfirmDeleteKey(null);
+      invalidateIssueDocuments();
+    },
+    onError: (err) => {
+      setError(err instanceof Error ? err.message : "Failed to delete document");
+    },
+  });
+
+  const sortedDocuments = useMemo(() => {
+    return [...(documents ?? [])].sort((a, b) => {
+      if (a.key === "plan" && b.key !== "plan") return -1;
+      if (a.key !== "plan" && b.key === "plan") return 1;
+      return new Date(b.updatedAt).getTime() - new Date(a.updatedAt).getTime();
+    });
+  }, [documents]);
+
+  const hasRealPlan = sortedDocuments.some((doc) => doc.key === "plan");
+
+  const beginNewDocument = () => {
+    reset();
+    setDraft({
+      key: "",
+      title: "",
+      body: "",
+      baseRevisionId: null,
+      isNew: true,
+    });
+    setError(null);
+  };
+
+  const beginEdit = (key: string) => {
+    const doc = sortedDocuments.find((entry) => entry.key === key);
+    if (!doc) return;
+    reset();
+    setDraft({
+      key: doc.key,
+      title: doc.title ?? "",
+      body: doc.body,
+      baseRevisionId: doc.latestRevisionId,
+      isNew: false,
+    });
+    setError(null);
+  };
+
+  const cancelDraft = () => {
+    if (autosaveDebounceRef.current) {
+      clearTimeout(autosaveDebounceRef.current);
+    }
+    reset();
+    setDraft(null);
+    setError(null);
+  };
+
+  const commitDraft = useCallback(async (
+    currentDraft: DraftState | null,
+    options?: { clearAfterSave?: boolean; trackAutosave?: boolean },
+  ) => {
+    if (!currentDraft || upsertDocument.isPending) return false;
+    const normalizedKey = currentDraft.key.trim().toLowerCase();
+    const normalizedBody = currentDraft.body.trim();
+    const normalizedTitle = currentDraft.title.trim();
+
+    if (!normalizedKey || !normalizedBody) {
+      if (currentDraft.isNew) {
+        setError("Document key and body are required");
+      } else if (!normalizedBody) {
+        setError("Document body cannot be empty");
+      }
+      if (options?.trackAutosave) {
+        reset();
+      }
+      return false;
+    }
+
+    const existing = sortedDocuments.find((doc) => doc.key === normalizedKey);
+    if (
+      !currentDraft.isNew &&
+      existing &&
+      existing.body === currentDraft.body &&
+      (existing.title ?? "") === currentDraft.title
+    ) {
+      if (options?.clearAfterSave) {
+        setDraft((value) => (value?.key === normalizedKey ? null : value));
+      }
+      if (options?.trackAutosave) {
+        reset();
+      }
+      return true;
+    }
+
+    const save = async () => {
+      const saved = await upsertDocument.mutateAsync({
+        ...currentDraft,
+        key: normalizedKey,
+        title: isPlanKey(normalizedKey) ? "" : normalizedTitle,
+        body: currentDraft.body,
+      });
+      setError(null);
+      setDraft((value) => {
+        if (!value || value.key !== normalizedKey) return value;
+        if (options?.clearAfterSave) return null;
+        return {
+          key: saved.key,
+          title: saved.title ?? "",
+          body: saved.body,
+          baseRevisionId: saved.latestRevisionId,
+          isNew: false,
+        };
+      });
+      invalidateIssueDocuments();
+    };
+
+    try {
+      if (options?.trackAutosave) {
+        await runSave(save);
+      } else {
+        await save();
+      }
+      return true;
+    } catch (err) {
+      setError(err instanceof Error ? err.message : "Failed to save document");
+      return false;
+    }
+  }, [invalidateIssueDocuments, reset, runSave, sortedDocuments, upsertDocument]);
+
+  const handleDraftBlur = async (event: React.FocusEvent<HTMLDivElement>) => {
+    if (event.currentTarget.contains(event.relatedTarget as Node | null)) return;
+    if (autosaveDebounceRef.current) {
+      clearTimeout(autosaveDebounceRef.current);
+    }
+    await commitDraft(draft, { clearAfterSave: true, trackAutosave: true });
+  };
+
+  const handleDraftKeyDown = async (event: React.KeyboardEvent) => {
+    if (event.key === "Escape") {
+      event.preventDefault();
+      cancelDraft();
+      return;
+    }
+    if ((event.metaKey || event.ctrlKey) && event.key === "Enter") {
+      event.preventDefault();
+      if (autosaveDebounceRef.current) {
+        clearTimeout(autosaveDebounceRef.current);
+      }
+      await commitDraft(draft, { clearAfterSave: false, trackAutosave: true });
+    }
+  };
+
+  useEffect(() => {
+    return () => {
+      if (autosaveDebounceRef.current) {
+        clearTimeout(autosaveDebounceRef.current);
+      }
+    };
+  }, []);
+
+  useEffect(() => {
+    if (!draft || draft.isNew) return;
+    const existing = sortedDocuments.find((doc) => doc.key === draft.key);
+    if (!existing) return;
+    const hasChanges =
+      existing.body !== draft.body ||
+      (existing.title ?? "") !== draft.title;
+    if (!hasChanges) {
+      if (autosaveState !== "saved") {
+        reset();
+      }
+      return;
+    }
+    markDirty();
+    if (autosaveDebounceRef.current) {
+      clearTimeout(autosaveDebounceRef.current);
+    }
+    autosaveDebounceRef.current = setTimeout(() => {
+      void commitDraft(draft, { clearAfterSave: false, trackAutosave: true });
+    }, DOCUMENT_AUTOSAVE_DEBOUNCE_MS);
+
+    return () => {
+      if (autosaveDebounceRef.current) {
+        clearTimeout(autosaveDebounceRef.current);
+      }
+    };
+  }, [autosaveState, commitDraft, draft, markDirty, reset, sortedDocuments]);
+
+  const documentBodyShellClassName = "mt-3 overflow-hidden rounded-md border border-border bg-background";
+  const documentBodyPaddingClassName = "px-3 py-3";
+  const documentBodyContentClassName = "paperclip-edit-in-place-content min-h-[220px] text-[15px] leading-7";
+
+  return (
+    <div className="space-y-3">
+      <div className="flex items-center justify-between gap-2">
+        <h3 className="text-sm font-medium text-muted-foreground">Documents</h3>
+        <Button variant="outline" size="sm" onClick={beginNewDocument}>
+          <Plus className="mr-1.5 h-3.5 w-3.5" />
+          New document
+        </Button>
+      </div>
+
+      {error && <p className="text-xs text-destructive">{error}</p>}
+
+      {draft?.isNew && (
+        <div
+          className="space-y-3 rounded-lg border border-border bg-accent/10 p-3"
+          onBlurCapture={handleDraftBlur}
+          onKeyDown={handleDraftKeyDown}
+        >
+          <Input
+            autoFocus
+            value={draft.key}
+            onChange={(event) =>
+              setDraft((current) => current ? { ...current, key: event.target.value.toLowerCase() } : current)
+            }
+            placeholder="Document key"
+          />
+          {!isPlanKey(draft.key) && (
+            <Input
+              value={draft.title}
+              onChange={(event) =>
+                setDraft((current) => current ? { ...current, title: event.target.value } : current)
+              }
+              placeholder="Optional title"
+            />
+          )}
+          <MarkdownEditor
+            value={draft.body}
+            onChange={(body) =>
+              setDraft((current) => current ? { ...current, body } : current)
+            }
+            placeholder="Markdown body"
+            bordered={false}
+            className="bg-transparent"
+            contentClassName="min-h-[220px] px-3 py-3 text-[15px] leading-7"
+            mentions={mentions}
+            imageUploadHandler={imageUploadHandler}
+            onSubmit={() => void commitDraft(draft, { clearAfterSave: false, trackAutosave: false })}
+          />
+          <div className="flex items-center justify-end gap-2">
+            <Button variant="outline" size="sm" onClick={cancelDraft}>
+              <X className="mr-1.5 h-3.5 w-3.5" />
+              Cancel
+            </Button>
+            <Button
+              size="sm"
+              onClick={() => void commitDraft(draft, { clearAfterSave: false, trackAutosave: false })}
+              disabled={upsertDocument.isPending}
+            >
+              {upsertDocument.isPending ? "Saving..." : "Create document"}
+            </Button>
+          </div>
+        </div>
+      )}
+
+      {sortedDocuments.length === 0 && !issue.legacyPlanDocument ? (
+        <p className="text-xs text-muted-foreground">No documents yet.</p>
+      ) : null}
+
+      {!hasRealPlan && issue.legacyPlanDocument ? (
+        <div className="rounded-lg border border-amber-500/30 bg-amber-500/5 p-3">
+          <div className="mb-2 flex items-center gap-2">
+            <FileText className="h-4 w-4 text-amber-600" />
+            <span className="rounded-full border border-amber-500/30 px-2 py-0.5 font-mono text-[10px] uppercase tracking-[0.16em] text-amber-700 dark:text-amber-300">
+              PLAN
+            </span>
+          </div>
+          <div className={documentBodyPaddingClassName}>
+            {renderBody(issue.legacyPlanDocument.body, documentBodyContentClassName)}
+          </div>
+        </div>
+      ) : null}
+
+      <div className="space-y-3">
+        {sortedDocuments.map((doc) => {
+          const activeDraft = draft?.key === doc.key && !draft.isNew ? draft : null;
+          const showTitle = !isPlanKey(doc.key) && !!doc.title?.trim();
+
+          return (
+            <div key={doc.id} className="rounded-lg border border-border p-3">
+              <div className="flex items-start justify-between gap-3">
+                <div className="min-w-0">
+                  <div className="flex items-center gap-2">
+                    <span className="rounded-full border border-border px-2 py-0.5 font-mono text-[10px] uppercase tracking-[0.16em] text-muted-foreground">
+                      {doc.key}
+                    </span>
+                    <span className="text-[11px] text-muted-foreground">
+                      rev {doc.latestRevisionNumber} • updated {relativeTime(doc.updatedAt)}
+                    </span>
+                  </div>
+                  {showTitle && <p className="mt-2 text-sm font-medium">{doc.title}</p>}
+                </div>
+                {canDeleteDocuments && (
+                  <DropdownMenu>
+                    <DropdownMenuTrigger asChild>
+                      <Button
+                        variant="ghost"
+                        size="icon-xs"
+                        className="text-muted-foreground"
+                        title="Document actions"
+                      >
+                        <MoreHorizontal className="h-3.5 w-3.5" />
+                      </Button>
+                    </DropdownMenuTrigger>
+                    <DropdownMenuContent align="end">
+                      <DropdownMenuSeparator />
+                      <DropdownMenuItem
+                        variant="destructive"
+                        onClick={() => setConfirmDeleteKey(doc.key)}
+                      >
+                        <Trash2 className="h-3.5 w-3.5" />
+                        Delete document
+                      </DropdownMenuItem>
+                    </DropdownMenuContent>
+                  </DropdownMenu>
+                )}
+              </div>
+
+              <div
+                className="mt-3 space-y-3"
+                onFocusCapture={() => {
+                  if (!activeDraft) {
+                    beginEdit(doc.key);
+                  }
+                }}
+                onBlurCapture={async (event) => {
+                  if (activeDraft) {
+                    await handleDraftBlur(event);
+                  }
+                }}
+                onKeyDown={async (event) => {
+                  if (activeDraft) {
+                    await handleDraftKeyDown(event);
+                  }
+                }}
+              >
+                {activeDraft && !isPlanKey(doc.key) && (
+                  <Input
+                    value={activeDraft.title}
+                    onChange={(event) => {
+                      markDirty();
+                      setDraft((current) => current ? { ...current, title: event.target.value } : current);
+                    }}
+                    placeholder="Optional title"
+                  />
+                )}
+                <div
+                  className={`${documentBodyShellClassName} ${documentBodyPaddingClassName} ${
+                    activeDraft ? "" : "hover:bg-accent/10"
+                  }`}
+                >
+                  <MarkdownEditor
+                    value={activeDraft?.body ?? doc.body}
+                    onChange={(body) => {
+                      markDirty();
+                      setDraft((current) => {
+                        if (current && current.key === doc.key && !current.isNew) {
+                          return { ...current, body };
+                        }
+                        return {
+                          key: doc.key,
+                          title: doc.title ?? "",
+                          body,
+                          baseRevisionId: doc.latestRevisionId,
+                          isNew: false,
+                        };
+                      });
+                    }}
+                    placeholder="Markdown body"
+                    bordered={false}
+                    className="bg-transparent"
+                    contentClassName={documentBodyContentClassName}
+                    mentions={mentions}
+                    imageUploadHandler={imageUploadHandler}
+                    onSubmit={() => void commitDraft(activeDraft ?? draft, { clearAfterSave: false, trackAutosave: true })}
+                  />
+                </div>
+                <div className="flex min-h-4 items-center justify-end px-1">
+                  <span
+                    className={`text-[11px] transition-opacity duration-150 ${
+                      autosaveState === "error" ? "text-destructive" : "text-muted-foreground"
+                    } ${activeDraft ? "opacity-100" : "opacity-0"}`}
+                  >
+                    {activeDraft
+                      ? autosaveState === "saving"
+                        ? "Autosaving..."
+                        : autosaveState === "saved"
+                          ? "Saved"
+                          : autosaveState === "error"
+                            ? "Could not save"
+                            : ""
+                      : ""}
+                  </span>
+                </div>
+              </div>
+
+              {confirmDeleteKey === doc.key && (
+                <div className="mt-3 flex items-center justify-between gap-3 rounded-md border border-destructive/20 bg-destructive/5 px-4 py-3">
+                  <p className="text-sm text-destructive font-medium">
+                    Delete this document? This cannot be undone.
+                  </p>
+                  <div className="flex items-center gap-2 shrink-0">
+                    <Button
+                      variant="ghost"
+                      size="sm"
+                      onClick={() => setConfirmDeleteKey(null)}
+                      disabled={deleteDocument.isPending}
+                    >
+                      Cancel
+                    </Button>
+                    <Button
+                      variant="destructive"
+                      size="sm"
+                      onClick={() => deleteDocument.mutate(doc.key)}
+                      disabled={deleteDocument.isPending}
+                    >
+                      {deleteDocument.isPending ? "Deleting..." : "Delete"}
+                    </Button>
+                  </div>
+                </div>
+              )}
+            </div>
+          );
+        })}
+      </div>
+    </div>
+  );
+}
--- a/ui/src/hooks/useAutosaveIndicator.ts
+++ b/ui/src/hooks/useAutosaveIndicator.ts
@@ -0,0 +1,72 @@
+import { useCallback, useEffect, useRef, useState } from "react";
+
+export type AutosaveState = "idle" | "saving" | "saved" | "error";
+
+const SAVING_DELAY_MS = 250;
+const SAVED_LINGER_MS = 1600;
+
+export function useAutosaveIndicator() {
+  const [state, setState] = useState<AutosaveState>("idle");
+  const saveIdRef = useRef(0);
+  const savingTimerRef = useRef<ReturnType<typeof setTimeout> | null>(null);
+  const clearSavedTimerRef = useRef<ReturnType<typeof setTimeout> | null>(null);
+
+  const clearTimers = useCallback(() => {
+    if (savingTimerRef.current) {
+      clearTimeout(savingTimerRef.current);
+      savingTimerRef.current = null;
+    }
+    if (clearSavedTimerRef.current) {
+      clearTimeout(clearSavedTimerRef.current);
+      clearSavedTimerRef.current = null;
+    }
+  }, []);
+
+  useEffect(() => clearTimers, [clearTimers]);
+
+  const reset = useCallback(() => {
+    saveIdRef.current += 1;
+    clearTimers();
+    setState("idle");
+  }, [clearTimers]);
+
+  const markDirty = useCallback(() => {
+    clearTimers();
+    setState("idle");
+  }, [clearTimers]);
+
+  const runSave = useCallback(async (save: () => Promise<void>) => {
+    const saveId = saveIdRef.current + 1;
+    saveIdRef.current = saveId;
+    clearTimers();
+    savingTimerRef.current = setTimeout(() => {
+      if (saveIdRef.current === saveId) {
+        setState("saving");
+      }
+    }, SAVING_DELAY_MS);
+
+    try {
+      await save();
+      if (saveIdRef.current !== saveId) return;
+      clearTimers();
+      setState("saved");
+      clearSavedTimerRef.current = setTimeout(() => {
+        if (saveIdRef.current === saveId) {
+          setState("idle");
+        }
+      }, SAVED_LINGER_MS);
+    } catch (error) {
+      if (saveIdRef.current !== saveId) throw error;
+      clearTimers();
+      setState("error");
+      throw error;
+    }
+  }, [clearTimers]);
+
+  return {
+    state,
+    markDirty,
+    reset,
+    runSave,
+  };
+}
--- a/ui/src/index.css
+++ b/ui/src/index.css
@@ -307,6 +307,11 @@
  color: inherit;
 }

+.paperclip-edit-in-place-content {
+  font-size: 0.9375rem;
+  line-height: 1.75rem;
+}
+
 .paperclip-mdxeditor-content > *:first-child {
  margin-top: 0;
 }
@@ -317,11 +322,11 @@

 .paperclip-mdxeditor-content p {
  margin: 0;
-  line-height: 1.4;
+  line-height: inherit;
 }

 .paperclip-mdxeditor-content p + p {
-  margin-top: 0.6rem;
+  margin-top: 1.1em;
 }

 .paperclip-mdxeditor-content a.paperclip-project-mention-chip {
@@ -342,8 +347,8 @@

 .paperclip-mdxeditor-content ul,
 .paperclip-mdxeditor-content ol {
-  margin: 0.35rem 0;
-  padding-left: 1.1rem;
+  margin: 1.1em 0;
+  padding-left: 1.6em;
 }

 .paperclip-mdxeditor-content ul {
@@ -356,32 +361,46 @@

 .paperclip-mdxeditor-content li {
  display: list-item;
-  margin: 0.15rem 0;
-  line-height: 1.4;
+  margin: 0.3em 0;
+  line-height: inherit;
 }

 .paperclip-mdxeditor-content li::marker {
  color: var(--muted-foreground);
 }

-.paperclip-mdxeditor-content h1,
-.paperclip-mdxeditor-content h2,
-.paperclip-mdxeditor-content h3 {
-  margin: 0.4rem 0 0.25rem;
+.paperclip-mdxeditor-content h1 {
+  margin: 0 0 0.9em;
+  font-size: 1.75em;
+  font-weight: 700;
+  line-height: 1.2;
+}
+
+.paperclip-mdxeditor-content h2 {
+  margin: 0 0 0.85em;
+  font-size: 1.35em;
+  font-weight: 700;
  line-height: 1.3;
 }

+.paperclip-mdxeditor-content h3 {
+  margin: 0 0 0.8em;
+  font-size: 1.15em;
+  font-weight: 600;
+  line-height: 1.35;
+}
+
 .paperclip-mdxeditor-content img {
  max-height: 18rem;
  border-radius: calc(var(--radius) - 2px);
 }

 .paperclip-mdxeditor-content blockquote {
-  margin: 0.45rem 0;
-  padding-left: 0.7rem;
-  border-left: 2px solid var(--border);
+  margin: 1.2em 0;
+  padding-left: 1em;
+  border-left: 3px solid var(--border);
  color: var(--muted-foreground);
-  line-height: 1.4;
+  line-height: inherit;
 }

 .paperclip-mdxeditor-content code {
--- a/ui/src/lib/queryKeys.ts
+++ b/ui/src/lib/queryKeys.ts
@@ -27,6 +27,8 @@ export const queryKeys = {
    detail: (id: string) => ["issues", "detail", id] as const,
    comments: (issueId: string) => ["issues", "comments", issueId] as const,
    attachments: (issueId: string) => ["issues", "attachments", issueId] as const,
+    documents: (issueId: string) => ["issues", "documents", issueId] as const,
+    documentRevisions: (issueId: string, key: string) => ["issues", "document-revisions", issueId, key] as const,
    activity: (issueId: string) => ["issues", "activity", issueId] as const,
    runs: (issueId: string) => ["issues", "runs", issueId] as const,
    approvals: (issueId: string) => ["issues", "approvals", issueId] as const,
--- a/ui/src/pages/IssueDetail.tsx
+++ b/ui/src/pages/IssueDetail.tsx
@@ -1,4 +1,4 @@
-import { useEffect, useMemo, useRef, useState, type ChangeEvent } from "react";
+import { useEffect, useMemo, useRef, useState, type ChangeEvent, type DragEvent } from "react";
 import { Link, useLocation, useNavigate, useParams } from "@/lib/router";
 import { useQuery, useMutation, useQueryClient } from "@tanstack/react-query";
 import { issuesApi } from "../api/issues";
@@ -16,6 +16,7 @@ import { useProjectOrder } from "../hooks/useProjectOrder";
 import { relativeTime, cn, formatTokens } from "../lib/utils";
 import { InlineEditor } from "../components/InlineEditor";
 import { CommentThread } from "../components/CommentThread";
+import { IssueDocumentsSection } from "../components/IssueDocumentsSection";
 import { IssueProperties } from "../components/IssueProperties";
 import { LiveRunWidget } from "../components/LiveRunWidget";
 import type { MentionOption } from "../components/MarkdownEditor";
@@ -60,6 +61,9 @@ const ACTION_LABELS: Record<string, string> = {
  "issue.comment_added": "added a comment",
  "issue.attachment_added": "added an attachment",
  "issue.attachment_removed": "removed an attachment",
+  "issue.document_created": "created a document",
+  "issue.document_updated": "updated a document",
+  "issue.document_deleted": "deleted a document",
  "issue.deleted": "deleted the issue",
  "agent.created": "created an agent",
  "agent.updated": "updated the agent",
@@ -97,6 +101,36 @@ function truncate(text: string, max: number): string {
  return text.slice(0, max - 1) + "\u2026";
 }

+function isMarkdownFile(file: File) {
+  const name = file.name.toLowerCase();
+  return (
+    name.endsWith(".md") ||
+    name.endsWith(".markdown") ||
+    file.type === "text/markdown"
+  );
+}
+
+function fileBaseName(filename: string) {
+  return filename.replace(/\.[^.]+$/, "");
+}
+
+function slugifyDocumentKey(input: string) {
+  const slug = input
+    .trim()
+    .toLowerCase()
+    .replace(/[^a-z0-9]+/g, "-")
+    .replace(/^-+|-+$/g, "");
+  return slug || "document";
+}
+
+function titleizeFilename(input: string) {
+  return input
+    .split(/[-_ ]+/g)
+    .filter(Boolean)
+    .map((part) => part.charAt(0).toUpperCase() + part.slice(1))
+    .join(" ");
+}
+
 function formatAction(action: string, details?: Record<string, unknown> | null): string {
  if (action === "issue.updated" && details) {
    const previous = (details._previous ?? {}) as Record<string, unknown>;
@@ -130,6 +164,14 @@ function formatAction(action: string, details?: Record<string, unknown> | null):

    if (parts.length > 0) return parts.join(", ");
  }
+  if (
+    (action === "issue.document_created" || action === "issue.document_updated" || action === "issue.document_deleted") &&
+    details
+  ) {
+    const key = typeof details.key === "string" ? details.key : "document";
+    const title = typeof details.title === "string" && details.title ? ` (${details.title})` : "";
+    return `${ACTION_LABELS[action] ?? action} ${key}${title}`;
+  }
  return ACTION_LABELS[action] ?? action.replace(/[._]/g, " ");
 }

@@ -160,6 +202,7 @@ export function IssueDetail() {
    cost: false,
  });
  const [attachmentError, setAttachmentError] = useState<string | null>(null);
+  const [attachmentDragActive, setAttachmentDragActive] = useState(false);
  const fileInputRef = useRef<HTMLInputElement | null>(null);
  const lastMarkedReadIssueIdRef = useRef<string | null>(null);

@@ -384,6 +427,7 @@ export function IssueDetail() {
    queryClient.invalidateQueries({ queryKey: queryKeys.issues.runs(issueId!) });
    queryClient.invalidateQueries({ queryKey: queryKeys.issues.approvals(issueId!) });
    queryClient.invalidateQueries({ queryKey: queryKeys.issues.attachments(issueId!) });
+    queryClient.invalidateQueries({ queryKey: queryKeys.issues.documents(issueId!) });
    queryClient.invalidateQueries({ queryKey: queryKeys.issues.liveRuns(issueId!) });
    queryClient.invalidateQueries({ queryKey: queryKeys.issues.activeRun(issueId!) });
    if (selectedCompanyId) {
@@ -458,6 +502,30 @@ export function IssueDetail() {
    },
  });

+  const importMarkdownDocument = useMutation({
+    mutationFn: async (file: File) => {
+      const baseName = fileBaseName(file.name);
+      const key = slugifyDocumentKey(baseName);
+      const existing = (issue?.documentSummaries ?? []).find((doc) => doc.key === key) ?? null;
+      const body = await file.text();
+      const inferredTitle = titleizeFilename(baseName);
+      const nextTitle = existing?.title ?? inferredTitle ?? null;
+      return issuesApi.upsertDocument(issueId!, key, {
+        title: key === "plan" ? null : nextTitle,
+        format: "markdown",
+        body,
+        baseRevisionId: existing?.latestRevisionId ?? null,
+      });
+    },
+    onSuccess: () => {
+      setAttachmentError(null);
+      invalidateIssue();
+    },
+    onError: (err) => {
+      setAttachmentError(err instanceof Error ? err.message : "Document import failed");
+    },
+  });
+
  const deleteAttachment = useMutation({
    mutationFn: (attachmentId: string) => issuesApi.deleteAttachment(attachmentId),
    onSuccess: () => {
@@ -509,14 +577,34 @@ export function IssueDetail() {
  const ancestors = issue.ancestors ?? [];

  const handleFilePicked = async (evt: ChangeEvent<HTMLInputElement>) => {
-    const file = evt.target.files?.[0];
-    if (!file) return;
+    const files = evt.target.files;
+    if (!files || files.length === 0) return;
+    for (const file of Array.from(files)) {
+      if (isMarkdownFile(file)) {
+        await importMarkdownDocument.mutateAsync(file);
+      } else {
        await uploadAttachment.mutateAsync(file);
+      }
+    }
    if (fileInputRef.current) {
      fileInputRef.current.value = "";
    }
  };

+  const handleAttachmentDrop = async (evt: DragEvent<HTMLDivElement>) => {
+    evt.preventDefault();
+    setAttachmentDragActive(false);
+    const files = evt.dataTransfer.files;
+    if (!files || files.length === 0) return;
+    for (const file of Array.from(files)) {
+      if (isMarkdownFile(file)) {
+        await importMarkdownDocument.mutateAsync(file);
+      } else {
+        await uploadAttachment.mutateAsync(file);
+      }
+    }
+  };
+
  const isImageAttachment = (attachment: IssueAttachment) => attachment.contentType.startsWith("image/");

  return (
@@ -658,14 +746,14 @@ export function IssueDetail() {

        <InlineEditor
          value={issue.title}
-          onSave={(title) => updateIssue.mutate({ title })}
+          onSave={(title) => updateIssue.mutateAsync({ title })}
          as="h2"
          className="text-xl font-bold"
        />

        <InlineEditor
          value={issue.description ?? ""}
-          onSave={(description) => updateIssue.mutate({ description })}
+          onSave={(description) => updateIssue.mutateAsync({ description })}
          as="p"
          className="text-[15px] leading-7 text-foreground"
          placeholder="Add a description..."
@@ -678,25 +766,62 @@ export function IssueDetail() {
        />
      </div>

-      <div className="space-y-3">
+      <IssueDocumentsSection
+        issue={issue}
+        canDeleteDocuments={Boolean(session?.user?.id)}
+        mentions={mentionOptions}
+        imageUploadHandler={async (file) => {
+          const attachment = await uploadAttachment.mutateAsync(file);
+          return attachment.contentPath;
+        }}
+      />
+
+      <div
+        className={cn(
+          "space-y-3 rounded-lg transition-colors",
+        )}
+        onDragEnter={(evt) => {
+          evt.preventDefault();
+          setAttachmentDragActive(true);
+        }}
+        onDragOver={(evt) => {
+          evt.preventDefault();
+          setAttachmentDragActive(true);
+        }}
+        onDragLeave={(evt) => {
+          if (evt.currentTarget.contains(evt.relatedTarget as Node | null)) return;
+          setAttachmentDragActive(false);
+        }}
+        onDrop={(evt) => void handleAttachmentDrop(evt)}
+      >
        <div className="flex items-center justify-between gap-2">
          <h3 className="text-sm font-medium text-muted-foreground">Attachments</h3>
-          <div className="flex items-center gap-2">
+          <div
+            className={cn(
+              "rounded-md border border-dashed border-border p-1 transition-colors",
+              attachmentDragActive && "border-primary bg-primary/5",
+            )}
+          >
            <input
              ref={fileInputRef}
              type="file"
-              accept="image/png,image/jpeg,image/webp,image/gif"
+              accept="image/*,application/pdf,text/plain,text/markdown,application/json,text/csv,text/html,.md,.markdown"
              className="hidden"
              onChange={handleFilePicked}
+              multiple
            />
            <Button
              variant="outline"
              size="sm"
              onClick={() => fileInputRef.current?.click()}
-              disabled={uploadAttachment.isPending}
+              disabled={uploadAttachment.isPending || importMarkdownDocument.isPending}
+              className={cn(
+                "border-transparent bg-transparent shadow-none",
+                attachmentDragActive && "bg-transparent",
+              )}
            >
              <Paperclip className="h-3.5 w-3.5 mr-1.5" />
-              {uploadAttachment.isPending ? "Uploading..." : "Upload image"}
+              {uploadAttachment.isPending || importMarkdownDocument.isPending ? "Uploading..." : "Upload attachment"}
            </Button>
          </div>
        </div>