backnotprop__plannotator/AGENTS.md

Plannotator

A plan review UI for Claude Code that intercepts ExitPlanMode via hooks, letting users approve or request changes with annotated feedback. Also provides code review for git diffs and annotation of arbitrary markdown files.

Project Structure

plannotator/
├── apps/
│   ├── hook/                     # Claude Code plugin
│   │   ├── .claude-plugin/plugin.json
│   │   ├── commands/             # Slash commands (plannotator-review.md, plannotator-annotate.md)
│   │   ├── hooks/hooks.json      # PermissionRequest hook config
│   │   ├── server/index.ts       # Entry point (plan + review + annotate subcommands)
│   │   └── dist/                 # Built single-file apps (index.html, review.html)
│   ├── opencode-plugin/          # OpenCode plugin
│   │   ├── commands/             # Slash commands (plannotator-review.md, plannotator-annotate.md)
│   │   ├── index.ts              # Plugin entry with submit_plan tool + review/annotate event handlers
│   │   ├── plannotator.html      # Built plan review app
│   │   └── review-editor.html    # Built code review app
│   ├── marketing/                # Marketing site, docs, and blog (plannotator.ai)
│   │   └── astro.config.mjs      # Astro 5 static site with content collections
│   ├── paste-service/            # Paste service for short URL sharing
│   │   ├── core/                 # Platform-agnostic logic (handler, storage interface, cors)
│   │   ├── stores/               # Storage backends (fs, kv, s3)
│   │   └── targets/              # Deployment entries (bun.ts, cloudflare.ts)
│   ├── review/                   # Standalone review server (for development)
│   │   ├── index.html
│   │   ├── index.tsx
│   │   └── vite.config.ts
│   └── vscode-extension/         # VS Code extension — opens plans in editor tabs
│       ├── bin/                   # Router scripts (open-in-vscode, xdg-open)
│       ├── src/                   # extension.ts, cookie-proxy.ts, ipc-server.ts, panel-manager.ts, editor-annotations.ts, vscode-theme.ts
│       └── package.json           # Extension manifest (publisher: backnotprop)
├── packages/
│   ├── server/                   # Shared server implementation
│   │   ├── index.ts              # startPlannotatorServer(), handleServerReady()
│   │   ├── review.ts             # startReviewServer(), handleReviewServerReady()
│   │   ├── annotate.ts           # startAnnotateServer(), handleAnnotateServerReady()
│   │   ├── storage.ts            # Plan saving to disk (getPlanDir, savePlan, etc.)
│   │   ├── share-url.ts          # Server-side share URL generation for remote sessions
│   │   ├── remote.ts             # isRemoteSession(), getServerPort()
│   │   ├── browser.ts            # openBrowser()
│   │   ├── draft.ts              # Annotation draft persistence (~/.plannotator/drafts/)
│   │   ├── integrations.ts       # Obsidian, Bear integrations
│   │   ├── ide.ts                # VS Code diff integration (openEditorDiff)
│   │   ├── editor-annotations.ts  # VS Code editor annotation endpoints
│   │   └── project.ts            # Project name detection for tags
│   ├── ui/                       # Shared React components
│   │   ├── components/           # Viewer, Toolbar, Settings, etc.
│   │   │   ├── plan-diff/        # PlanDiffBadge, PlanDiffViewer, clean/raw diff views
│   │   │   └── sidebar/          # SidebarContainer, SidebarTabs, VersionBrowser
│   │   ├── utils/                # parser.ts, sharing.ts, storage.ts, planSave.ts, agentSwitch.ts, planDiffEngine.ts
│   │   ├── hooks/                # useSharing.ts, usePlanDiff.ts, useSidebar.ts, useLinkedDoc.ts, useAnnotationDraft.ts, useCodeAnnotationDraft.ts
│   │   └── types.ts
│   ├── shared/                   # Cross-package types (EditorAnnotation)
│   ├── editor/                   # Plan review App.tsx
│   └── review-editor/            # Code review UI
│       ├── App.tsx               # Main review app
│       ├── components/           # DiffViewer, FileTree, ReviewPanel
│       ├── demoData.ts           # Demo diff for standalone mode
│       └── index.css             # Review-specific styles
├── .claude-plugin/marketplace.json  # For marketplace install
└── legacy/                       # Old pre-monorepo code (reference only)

Installation

Via plugin marketplace (when repo is public):

/plugin marketplace add backnotprop/plannotator

Local testing:

claude --plugin-dir ./apps/hook

Environment Variables

Variable	Description
PLANNOTATOR_REMOTE	Set to 1 or true for remote mode (devcontainer, SSH). Uses fixed port and skips browser open.
PLANNOTATOR_PORT	Fixed port to use. Default: random locally, 19432 for remote sessions.
PLANNOTATOR_BROWSER	Custom browser to open plans in. macOS: app name or path. Linux/Windows: executable path.
PLANNOTATOR_SHARE_URL	Custom base URL for share links (self-hosted portal). Default: https://share.plannotator.ai.
PLANNOTATOR_PASTE_URL	Base URL of the paste service API for short URL sharing. Default: https://plannotator-paste.plannotator.workers.dev.

Legacy: SSH_TTY and SSH_CONNECTION are still detected. Prefer PLANNOTATOR_REMOTE=1 for explicit control.

Devcontainer/SSH usage:

export PLANNOTATOR_REMOTE=1
export PLANNOTATOR_PORT=9999

Plan Review Flow

Claude calls ExitPlanMode
        ↓
PermissionRequest hook fires
        ↓
Bun server reads plan from stdin JSON (tool_input.plan)
        ↓
Server starts on random port, opens browser
        ↓
User reviews plan, optionally adds annotations
        ↓
Approve → stdout: {"hookSpecificOutput":{"decision":{"behavior":"allow"}}}
Deny    → stdout: {"hookSpecificOutput":{"decision":{"behavior":"deny","message":"..."}}}

Code Review Flow

User runs /plannotator-review command
        ↓
Claude Code: plannotator review subcommand runs
OpenCode: event handler intercepts command
        ↓
git diff captures unstaged changes
        ↓
Review server starts, opens browser with diff viewer
        ↓
User annotates code, provides feedback
        ↓
Send Feedback → feedback sent to agent session
Approve → "LGTM" sent to agent session

Annotate Flow

User runs /plannotator-annotate <file.md> command
        ↓
Claude Code: plannotator annotate subcommand runs
OpenCode: event handler intercepts command
        ↓
Markdown file read from disk
        ↓
Annotate server starts (reuses plan editor HTML with mode:"annotate")
        ↓
User annotates markdown, provides feedback
        ↓
Send Annotations → feedback sent to agent session

Server API

Plan Server (packages/server/index.ts)

Endpoint	Method	Purpose
/api/plan	GET	Returns { plan, origin, previousPlan, versionInfo } (plan mode) or { plan, origin, mode: "archive", archivePlans } (archive mode)
/api/plan/version	GET	Fetch specific version (?v=N)
/api/plan/versions	GET	List all versions of current plan
/api/archive/plans	GET	List archived plan decisions (?customPath=)
/api/archive/plan	GET	Fetch archived plan content (?filename=&customPath=)
/api/done	POST	Close archive browser (archive mode only)
/api/approve	POST	Approve plan (body: planSave, agentSwitch, obsidian, bear, feedback)
/api/deny	POST	Deny plan (body: feedback, planSave)
/api/image	GET	Serve image by path query param
/api/upload	POST	Upload image, returns { path, originalName }
/api/obsidian/vaults	GET	Detect available Obsidian vaults
/api/reference/obsidian/files	GET	List vault markdown files as nested tree (?vaultPath=<path>)
/api/reference/obsidian/doc	GET	Read a vault markdown file (?vaultPath=<path>&path=<file>)
/api/plan/vscode-diff	POST	Open diff in VS Code (body: baseVersion)
/api/doc	GET	Serve linked .md/.mdx file (?path=<path>)
/api/draft	GET/POST/DELETE	Auto-save annotation drafts to survive server crashes
/api/editor-annotations	GET	List editor annotations (VS Code only)
/api/editor-annotation	POST/DELETE	Add or remove an editor annotation (VS Code only)

Review Server (packages/server/review.ts)

Endpoint	Method	Purpose
/api/diff	GET	Returns { rawPatch, gitRef, origin }
/api/file-content	GET	Returns { oldContent, newContent } for expandable diff context
/api/git-add	POST	Stage/unstage a file (body: { filePath, undo? })
/api/feedback	POST	Submit review (body: feedback, annotations, agentSwitch)
/api/image	GET	Serve image by path query param
/api/upload	POST	Upload image, returns { path, originalName }
/api/draft	GET/POST/DELETE	Auto-save annotation drafts to survive server crashes
/api/editor-annotations	GET	List editor annotations (VS Code only)
/api/editor-annotation	POST/DELETE	Add or remove an editor annotation (VS Code only)

Annotate Server (packages/server/annotate.ts)

Endpoint	Method	Purpose
/api/plan	GET	Returns { plan, origin, mode: "annotate", filePath }
/api/feedback	POST	Submit annotations (body: feedback, annotations)
/api/image	GET	Serve image by path query param
/api/upload	POST	Upload image, returns { path, originalName }
/api/draft	GET/POST/DELETE	Auto-save annotation drafts to survive server crashes

All servers use random ports locally or fixed port (19432) in remote mode.

Paste Service (apps/paste-service/)

Endpoint	Method	Purpose
/api/paste	POST	Store compressed plan data, returns { id }
/api/paste/:id	GET	Retrieve stored compressed data

Runs as a separate service on port 19433 (self-hosted) or as a Cloudflare Worker (hosted).

Plan Version History

Every plan is automatically saved to ~/.plannotator/history/{project}/{slug}/ on arrival, before the user sees the UI. Versions are numbered sequentially (001.md, 002.md, etc.). The slug is derived from the plan's first # Heading + today's date via generateSlug(), scoped by project name (git repo or cwd). Same heading on the same day = same slug = same plan being iterated on. Identical resubmissions are deduplicated (no new file if content matches the latest version).

This powers the version history API (/api/plan/version, /api/plan/versions) and the plan diff system.

History saves independently of the planSave user setting (which controls decision snapshots in ~/.plannotator/plans/). Storage functions live in packages/shared/storage.ts (runtime-agnostic, re-exported by packages/server/storage.ts). Pi copies the shared files at build time. Slug format: {sanitized-heading}-YYYY-MM-DD (heading first for readability).

Plan Diff

When a user denies a plan and Claude resubmits, the UI shows what changed between versions. A +N/-M badge appears below the document card; clicking it toggles between normal view and diff view.

Diff engine (packages/ui/utils/planDiffEngine.ts): Uses the diff npm package (diffLines()) to compute line-level diffs. Groups consecutive remove+add into "modified" blocks. Returns PlanDiffBlock[] and PlanDiffStats.

Two view modes (toggle via PlanDiffModeSwitcher):

• Rendered (PlanCleanDiffView): Color-coded left borders — green (added), red (removed/strikethrough), yellow (modified)
• Raw (PlanRawDiffView): Monospace +/- lines, git-style

State (packages/ui/hooks/usePlanDiff.ts): Manages base version selection, diff computation, and version fetching. The server sends previousPlan with the initial /api/plan response; the hook auto-diffs against it. Users can select any prior version from the sidebar Version Browser.

Sidebar (packages/ui/hooks/useSidebar.ts): Shared left sidebar with two tabs — Table of Contents and Version Browser. The "Auto-open Sidebar" setting controls whether it opens on load (TOC tab only).

Data Types

Location: packages/ui/types.ts

enum AnnotationType {
  DELETION = "DELETION",
  INSERTION = "INSERTION",
  REPLACEMENT = "REPLACEMENT",
  COMMENT = "COMMENT",
  GLOBAL_COMMENT = "GLOBAL_COMMENT",
}

interface ImageAttachment {
  path: string;   // temp file path
  name: string;   // human-readable label (e.g., "login-mockup")
}

interface Annotation {
  id: string;
  blockId: string;
  startOffset: number;
  endOffset: number;
  type: AnnotationType;
  text?: string; // For comment/replacement/insertion
  originalText: string; // The selected text
  createdA: number; // Timestamp
  author?: string; // Tater identity
  images?: ImageAttachment[]; // Attached images with names
  startMeta?: { parentTagName; parentIndex; textOffset };
  endMeta?: { parentTagName; parentIndex; textOffset };
}

interface Block {
  id: string;
  type: "paragraph" | "heading" | "blockquote" | "list-item" | "code" | "hr";
  content: string;
  level?: number; // For headings (1-6)
  language?: string; // For code blocks
  order: number;
  startLine: number;
}

Markdown Parser

Location: packages/ui/utils/parser.ts

parseMarkdownToBlocks(markdown) splits markdown into Block objects. Handles:

• Headings (#, ##, etc.)
• Code blocks (``` with language extraction)
• List items (-, *, 1.)
• Blockquotes (>)
• Horizontal rules (---)
• Paragraphs (default)

exportAnnotations(blocks, annotations, globalAttachments) generates human-readable feedback for Claude. Images are referenced by name: [image-name] /tmp/path....

Annotation System

Selection mode: User selects text → toolbar appears → choose annotation type Redline mode: User selects text → auto-creates DELETION annotation

Text highlighting uses web-highlighter library. Code blocks use manual <mark> wrapping (web-highlighter can't select inside <pre>).

URL Sharing

Location: packages/ui/utils/sharing.ts, packages/ui/hooks/useSharing.ts

Shares full plan + annotations via URL hash using deflate compression. For large plans, short URLs are created via the paste service (user must explicitly confirm).

Payload format:

// Image in shareable format: plain string (old) or [path, name] tuple (new)
type ShareableImage = string | [string, string];

interface SharePayload {
  p: string; // Plan markdown
  a: ShareableAnnotation[]; // Compact annotations
  g?: ShareableImage[]; // Global attachments
}

type ShareableAnnotation =
  | ["D", string, string | null, ShareableImage[]?] // [type, original, author, images?]
  | ["R", string, string, string | null, ShareableImage[]?] // [type, original, replacement, author, images?]
  | ["C", string, string, string | null, ShareableImage[]?] // [type, original, comment, author, images?]
  | ["I", string, string, string | null, ShareableImage[]?] // [type, context, newText, author, images?]
  | ["G", string, string | null, ShareableImage[]?]; // [type, comment, author, images?]

Compression pipeline:

1. JSON.stringify(payload)
2. CompressionStream('deflate-raw')
3. Base64 encode
4. URL-safe: replace +/= with -_

On load from shared URL:

1. Parse hash, decompress, restore annotations
2. Find text positions in rendered DOM via text search
3. Apply <mark> highlights
4. Clear hash from URL (prevents re-parse on refresh)

Settings Persistence

Location: packages/ui/utils/storage.ts, planSave.ts, agentSwitch.ts

Uses cookies (not localStorage) because each hook invocation runs on a random port. Settings include identity, plan saving (enabled/custom path), and agent switching (OpenCode only).

Syntax Highlighting

Code blocks use bundled highlight.js. Language is extracted from fence (```rust) and applied as language-{lang}class. Each block highlighted individually viahljs.highlightElement().

Requirements

• Bun runtime
• Claude Code with plugin/hooks support, or OpenCode
• Cross-platform: macOS (open), Linux (xdg-open), Windows (start)

Development

bun install

# Run any app
bun run dev:hook       # Hook server (plan review)
bun run dev:review     # Review editor (code review)
bun run dev:portal     # Portal editor
bun run dev:marketing  # Marketing site
bun run dev:vscode     # VS Code extension (watch mode)

Build

bun run build:hook       # Single-file HTML for hook server
bun run build:review     # Code review editor
bun run build:opencode   # OpenCode plugin (copies HTML from hook + review)
bun run build:portal     # Static build for share.plannotator.ai
bun run build:marketing  # Static build for plannotator.ai
bun run build:vscode     # VS Code extension bundle
bun run package:vscode   # Package .vsix for marketplace
bun run build            # Build hook + opencode (main targets)

Important: The OpenCode plugin copies pre-built HTML from apps/hook/dist/ and apps/review/dist/. When making UI changes (in packages/ui/, packages/editor/, or packages/review-editor/), you must rebuild the hook/review first:

bun run build:hook && bun run build:opencode   # For UI changes

Running only build:opencode will copy stale HTML files.

Marketing Site

apps/marketing/ is the plannotator.ai website — landing page, documentation, and blog. Built with Astro 5 (static output, zero client JS except a theme toggle island). Docs are markdown files in src/content/docs/, blog posts in src/content/blog/, both using Astro content collections. Tailwind CSS v4 via @tailwindcss/vite. Deploys to S3/CloudFront via GitHub Actions on push to main.

Test plugin locally

claude --plugin-dir ./apps/hook