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Danila Poyarkov 048a8fbbc1
feat(settings): configure tool access, MCP failures, and step limits
* feat(settings): configure tool access and agent step limits

Built-in AI exposed only a hardcoded subset of the tool registry, and the
maximum agent steps was a constant, so users could neither enable
extended tools such as create_component nor adjust long-running tasks.

Built-in AI and the local MCP server now keep independent, locally saved
tool permissions over one shared catalog, with searchable read-only and
side-effect groups and per-target defaults. Chat settings gain a validated
maximum-steps field whose captured value drives the stop condition,
remaining-step warnings, and limit detection for each message.

Tool access, the local server, browser access, and MCP connections are
grouped under a single Automation settings page.

Closes #573
Closes #584

* refactor(settings): split automation into MCP and Tool access pages

The Automation page mixed a permission matrix with server endpoints behind
a Tools/Connections switch, and the view switch was indistinguishable from
the provider switch. The nested scroll region showed three of 110 tools.

Rename the MCP-facing page to MCP and give tool permissions their own Tool
access page. The page owns a fixed toolbar for the target, count, defaults,
and search, so the list uses the full dialog body and no row is clipped.

* fix(automation): explain MCP startup failures with localized guidance

Every startup failure collapsed into "MCP server did not become healthy":
the spawn layer recorded the real error but the runtime discarded it, and
health probes could not distinguish a rejected token from a missing server.
The message also surfaced raw English text as the alert heading.

Classify failures by reason (not installed, denied command, early exit,
startup timeout, rejected token, unexpected response, unreachable) and
render translated heading and guidance from the catalog, keeping captured
stderr or HTTP status as labeled diagnostic detail.

* refactor(ui): share one collapsible disclosure primitive

Six features each wired Reka's collapsible with their own motion classes and
one settings-only theme token, so the same interaction drifted in spacing,
icon size, and reduced-motion handling.

Add AppCollapsible with a family theme and move the settings disclosure and
the model editor's advanced settings onto it. Chat and frame-preset call
sites keep their distinct visuals for a follow-up.

* fix(automation): explain MCP failures with localized details

The failure alert carried raw English error text as its heading, and the
diagnostic payload sat in a sibling block outside the alert with no
relationship to it.

Classify failures by reason, render translated heading and guidance from
the catalog, and keep the payload in a collapsible inside the alert, which
unmounts while collapsed so the live region announces only the summary.
Add a copy action for issue reports.

Find the executable where a graphical launch can: extend PATH with the
common global bin directories before the lookup and report the searched
directories as diagnostic detail.

* fix(automation): keep MCP failure details out of reasons already explained

An unreachable address and a rejected token already name their cause in the
translated guidance, so repeating it under Details added noise. Details now
carry only output the summary cannot: stderr, HTTP status, or an unknown
error message.

* test(settings): browse every MCP failure reason in Storybook

The failure copy lived inside the settings panel, so reviewing the eight
reasons meant reproducing each failure and the mapping could only be
checked through the panel's dependencies.

Extract MCPFailureAlert, which owns the reason-to-copy mapping, detail
visibility, copy action, and restart action, and add a story covering
every reason plus the collapsed-details behavior.

* fix(ui): order alert details above the recovery actions

The alert rendered its action buttons before the details slot, so the
collapsible explanation of a failure appeared under the controls it
explains. Details now render directly after the description.

* fix(automation): correct MCP failure classification and detail

Review follow-ups on the failure diagnostics.

Only 401 and 403 mean the server refused our token; any other status now
reports an unexpected response instead of telling the user to replace a
token that was never the problem.

The install hint rendered the whole diagnostic detail as its package
argument, so searched directories appeared inside the install command.
The install target is now a domain constant and the searched directories
stay as detail, which not-installed failures surface again since they are
the actionable desktop diagnostic.

Exited failures also record the process exit code and signal so copied
diagnostics stay conclusive when stderr is empty. The bundled PATH test
now covers the append branch instead of only the unchanged path.

* feat(settings): accept custom values for presets and retention

Retention was a closed set of three counts while the AI step limit was a
free number, so two bounded numeric preferences looked and behaved
differently for no product reason.

Add a shared preset-or-custom field: presets stay one click, the escape
hatch reveals a validated numeric field, and the model carries only the
resolved number. Diagnostics retention becomes a bounded number (50 to
20,000) with the presets as shortcuts, and the hardcoded revalidation in
the panel is replaced by one domain resolver.

* fix(settings): label the preset and custom fields

Replacing the labeled provider field with the shared control left the AI
step limit as a bare select with a detached hint paragraph, outside the
settings group, so nothing on screen said what the number meant. The
accessibility name came from aria-label, which is why behavior tests
passed while the panel was unreadable.

Move both controls into labeled settings rows with their descriptions, and
give the revealed field its own accessible name so the two controls in one
row differ. The specs now assert the control lives inside the row that
names it, which is the check that would have caught this.

* fix(mcp): allow the desktop app origin by default

A server started manually bound the port and answered curl but the app
webview could not use it: no CORS origin was configured, so the browser
blocked every fetch and the app reported the server as unhealthy. The
workaround required an undocumented environment variable.

Allow the desktop app origins by default, accept a comma-separated
override, and document the default in the CLI help and the security notes.
Authenticated requests still need the bearer token, and browsers set Origin
themselves, so only the app webview can present these origins.

* fix(settings): address review findings on the new controls

Copy details awaited nothing and confirmed the copy before the write
finished. VueUse never rejects and falls back to a legacy write, so the
await is what makes the confirmation honest rather than an error branch.

The preset field only left custom mode when a preset arrived; a non-preset
value assigned from the owner left the select showing a value absent from
its options with the field still hidden. The watcher now follows the model
in both directions.

The story play functions queried the revealed field by the row label, which
Testing Library matches as a whole string, so those interactions could not
find it. The Storybook smoke assertion also assumed a button or tab, which
skipped every story built from other primitives.
2026-09-17 23:55:58 +03:00
.claude ci: keep AI disclosure out of co-author credits 2026-09-15 23:12:44 +03:00
.devcontainer chore: add reproducible Dev Container (#510) 2026-08-14 13:19:55 +03:00
.github fix: use official Homebrew cask installation guidance (#712) 2026-09-17 13:36:17 +03:00
.storybook feat: refresh branding with generated platform icons (#707) 2026-09-16 11:54:07 +03:00
.vscode
assets/brand feat: refresh branding with generated platform icons (#707) 2026-09-16 11:54:07 +03:00
desktop feat(settings): configure tool access, MCP failures, and step limits 2026-09-17 23:55:58 +03:00
lint refactor: replace complex conditional object spreads 2026-09-01 19:49:57 +03:00
packages feat(settings): configure tool access, MCP failures, and step limits 2026-09-17 23:55:58 +03:00
public feat: refresh branding with generated platform icons (#707) 2026-09-16 11:54:07 +03:00
scripts refactor(tools): organize internal CLI workflows (#600) 2026-08-29 14:42:44 +03:00
skills/open-pencil feat(settings): configure tool access, MCP failures, and step limits 2026-09-17 23:55:58 +03:00
src feat(settings): configure tool access, MCP failures, and step limits 2026-09-17 23:55:58 +03:00
tests feat(settings): configure tool access, MCP failures, and step limits 2026-09-17 23:55:58 +03:00
tools feat(settings): configure tool access, MCP failures, and step limits 2026-09-17 23:55:58 +03:00
vite chore: merge master into live-editor-regressions 2026-09-16 15:06:30 +03:00
.coderabbit.yaml chore: hide review status chatter and test generation prompts 2026-09-15 21:43:04 +03:00
.gitattributes
.gitignore feat: refresh branding with generated platform icons (#707) 2026-09-16 11:54:07 +03:00
.gitleaks.toml chore(tools): add secret scanning gate 2026-07-01 15:24:06 +03:00
.lfsconfig ci: move Git LFS to provider-neutral gateway 2026-08-01 17:52:08 +03:00
.oxfmtrc.json
AGENTS.md fix: use official Homebrew cask installation guidance (#712) 2026-09-17 13:36:17 +03:00
bun.lock fix: protect unsaved documents and defer credential access (#713) 2026-09-17 15:25:15 +03:00
bunfig.toml refactor(mcp): align transport domain structure 2026-07-25 22:59:59 +03:00
CHANGELOG.md feat(settings): configure tool access, MCP failures, and step limits 2026-09-17 23:55:58 +03:00
commitlint.config.ts ci: keep AI disclosure out of co-author credits 2026-09-15 23:12:44 +03:00
CONTRIBUTING.md docs(testing): define source-owned test architecture 2026-09-16 15:28:47 +03:00
index.html feat: refresh branding with generated platform icons (#707) 2026-09-16 11:54:07 +03:00
knip.json fix(text): finalize font readiness and label shaping (#593) 2026-08-30 14:33:32 +03:00
LICENSE docs: acknowledge OpenPencil contributors in license 2026-08-31 09:11:10 +03:00
oxlint.json refactor: narrow lint policies and consolidate their support 2026-09-14 10:10:27 +03:00
package.json fix: protect unsaved documents and defer credential access (#713) 2026-09-17 15:25:15 +03:00
playwright.config.ts chore: merge master into live-editor-regressions 2026-09-16 00:14:31 +03:00
portless.json chore: add Portless development URLs 2026-08-20 08:15:54 +03:00
README.md fix: use official Homebrew cask installation guidance (#712) 2026-09-17 13:36:17 +03:00
SECURITY.md
steiger.config.ts fix(ui): refine export scale control 2026-07-01 08:08:44 +03:00
tsconfig.json feat(editor): checkpoint live interaction improvements 2026-09-15 11:36:17 +03:00
tsconfig.node.json ci: validate PR commits and streamline package verification 2026-09-15 20:51:33 +03:00
vite.config.ts chore: merge master into live-editor-regressions 2026-09-16 15:06:30 +03:00
wdio.conf.ts test(tauri): add native WebView interaction harness (#532) 2026-08-15 14:17:05 +03:00

OpenPencil

Open-source design editor. Opens .fig and .pen design files, includes built-in AI, and ships as a programmable toolkit with a headless Vue SDK for building custom editors.

Status: Active development. Usable today, with some rough edges as features evolve.

Try it online → · Download · Documentation · Roadmap · llms.txt

OpenPencil

Installation

macOS (Homebrew):

brew install --cask openpencil

Or download from the releases page, or use the web app — no install needed.

What it does

  • Opens .fig and .pen files — read and write native Figma files, open supported Pencil documents from the app or OS file browser, copy & paste nodes between apps
  • AI builds designs — describe what you want in chat, 90+ tools create and modify nodes. Connect OpenRouter, Anthropic, OpenAI, Google AI, Z.ai, MiniMax, or compatible endpoints
  • Fully programmable — headless CLI, XPath queries, Figma Plugin API via eval, MCP server for AI agents, and desktop agent integrations for Claude Code, Codex, and Gemini CLI
  • Lint, convert, and extract tokens — inspect documents, lint naming/layout/accessibility, convert between supported formats, analyze colors/typography/spacing/clusters, and extract design tokens
  • Components and variants — create reusable components, group variants into component sets, insert local assets as instances, and switch variants from the inspector
  • Image vectorization — convert image layers into editable vector layers with Recraft or fal.ai
  • Design-to-code export — export selections as JSX/Tailwind, generate token outputs, and map designs into component-oriented code workflows
  • Vue SDK for custom editors — headless components and composables for embedding OpenPencil into other apps or building workflow-specific editing surfaces. Read the SDK docs →
  • Real-time collaboration — P2P via WebRTC, no server, no account. Cursors, presence, follow mode
  • Auto layout & CSS Grid — flex and grid layout via Yoga WASM, with gap, padding, alignment, track sizing
  • ~7 MB desktop app — Tauri v2 for macOS, Windows, Linux. Also runs in the browser as a PWA

CLI

npm install -g @open-pencil/cli
# or: bun add -g @open-pencil/cli

Inspect design files

Browse node trees, search by name or type, dig into properties — all without opening the editor:

openpencil tree design.fig
openpencil find design.pen --type TEXT
openpencil node design.fig --id 1:23
openpencil info design.fig
[0] [page] "Getting started" (0:46566)
  [0] [section] "" (0:46567)
    [0] [frame] "Body" (0:46568)
      [0] [frame] "Introduction" (0:46569)
        [0] [frame] "Introduction Card" (0:46570)
          [0] [frame] "Guidance" (0:46571)

Query with XPath

Use XPath selectors to find nodes by type, attributes, and structure:

openpencil query design.fig "//FRAME"                              # All frames
openpencil query design.fig "//FRAME[@width < 300]"                # Frames under 300px
openpencil query design.fig "//TEXT[contains(@name, 'Button')]"     # Text with 'Button' in name
openpencil query design.fig "//*[@cornerRadius > 0]"               # Rounded corners
openpencil query design.fig "//SECTION//TEXT"                       # Text inside sections

Export

Render to PNG, JPG, WEBP, SVG, .fig, or JSX — or export selections/pages as .fig and convert whole documents between supported formats:

openpencil export design.fig                           # PNG
openpencil export design.fig -f jpg -s 2 -q 90        # JPG at 2x, quality 90
openpencil export design.fig -f fig --page "Page 1"   # Export a page as .fig
openpencil export design.fig -f jsx --style tailwind   # Tailwind JSX
openpencil export design.fig -f html --css tailwind    # Tailwind HTML fragment
openpencil export design.fig -f html --html standalone --assets external # HTML + assets
openpencil convert design.pen output.fig               # Convert between document formats
openpencil import page.html --css styles.css -o page.fig # HTML/CSS → editable .fig

DOM/CSS input flows through @open-pencil/dom-css, so HTML, authored CSS, and Tailwind utility CSS can become editable OpenPencil layers:

openpencil import card.html --css card.css -o card.fig
openpencil import card.html --tailwind "flex flex-col gap-3 w-80 p-6 rounded-xl bg-white" -o card.fig
<div className="flex flex-col gap-4 p-6 bg-white rounded-xl">
  <p className="text-2xl font-bold text-[#1D1B20]">Card Title</p>
  <p className="text-sm text-[#49454F]">Description text</p>
</div>

Lint design files

Catch naming, layout, structure, and accessibility issues from the terminal:

openpencil lint design.fig
openpencil lint design.pen --preset strict
openpencil lint design.fig --rule color-contrast
openpencil lint design.fig --list-rules

Analyze and extract design tokens

Audit an entire design system from the terminal — find inconsistencies, extract the real palette, and spot components waiting to be extracted:

openpencil analyze colors design.fig
openpencil analyze typography design.fig
openpencil analyze spacing design.fig
openpencil analyze clusters design.fig
openpencil analyze overlaps design.fig
openpencil variables design.fig
#1d1b20  ██████████████████████████████ 17155×
#49454f  ██████████████████████████████ 9814×
#ffffff  ██████████████████████████████ 8620×
#6750a4  ██████████████████████████████ 3967×

3771× frame "container" (100% match)
     size: 40×40, structure: Frame > [Frame]

2982× instance "Checkboxes" (100% match)
     size: 48×48, structure: Instance > [Frame]

Script with Figma Plugin API

eval gives you the full Figma Plugin API. Modify the file, write it back:

openpencil eval design.fig -c "figma.currentPage.children.length"
openpencil eval design.fig -c "figma.currentPage.selection.forEach(n => n.opacity = 0.5)" -w

Control the running app

When the desktop app is running, omit the file argument — the CLI connects via RPC and operates on the live canvas. Useful for automation scripts, CI pipelines, or AI agents that need to interact with the editor:

openpencil tree                               # Inspect the live document
openpencil export -f png                      # Screenshot the current canvas
openpencil eval -c "figma.currentPage.name"   # Query the editor

All commands support --json for machine-readable output.

AI & MCP

Built-in chat

Press ⌘J to open the AI assistant. It has 100+ tools that can create shapes, set fills and strokes, manage auto-layout, work with components and variables, run boolean operations, analyze design tokens, and export assets. Bring your own API key for OpenRouter, Anthropic, OpenAI, Google AI, Z.ai, MiniMax, or compatible endpoints. No backend, no account.

Not every provider works in the browser, and not every model streams tool calls correctly. See BYOK provider & model compatibility for measured results — contributions welcome.

Coding agents (desktop)

Use Claude Code, Codex, or Gemini CLI directly in the chat panel. The agent connects to the editor's MCP server and uses all 100+ design tools. Requires the desktop app and the agent CLI installed locally.

Pi is also available as an optional AI SDK Harness provider. Install its companion CLI with npm install -g @open-pencil/harness, then add a Pi model profile in Settings → AI & agents. The companion is installed separately so OpenPencil does not bundle a JavaScript runtime for users who do not enable Harness providers.

Setup (Claude Code):

  1. Install the ACP adapter: npm install -g @agentclientprotocol/claude-agent-acp
  2. Add MCP permission to ~/.claude/settings.json:
    {
      "permissions": {
        "allow": ["mcp__open-pencil__*"]
      }
    }
    
  3. Open the desktop app → CtrlJ → select Claude Code from the provider dropdown

MCP server

Connect Claude Code, Cursor, Windsurf, or any MCP client to inspect, modify, and export design documents headlessly. 100+ tools. Full docs →

Stdio (Claude Code, Cursor, Windsurf):

npm install -g @open-pencil/mcp
claude mcp add --scope user open-pencil -- openpencil-mcp

For other MCP clients:

{
  "mcpServers": {
    "open-pencil": {
      "command": "openpencil-mcp"
    }
  }
}

HTTP (scripts, CI):

openpencil-mcp-http   # Unix socket on macOS/Linux + http://127.0.0.1:7600/mcp

Local clients discover the private Unix socket automatically and fall back to localhost TCP. Set PORT=0 to disable TCP on macOS/Linux.

File access: Set OPENPENCIL_MCP_ROOT to scope file operations (open_file, new_document, export path param) to a directory. Defaults to the current working directory.

AI agent skill

Teach your AI coding agent to use OpenPencil — inspect designs, export assets, analyze tokens, modify .fig files:

npx skills add open-pencil/open-pencil

Works with Claude Code, Cursor, Windsurf, Codex, and any agent that supports skills.

For documentation-aware agents, the docs site publishes llms.txt, llms-full.txt, and per-page Markdown files generated from the VitePress docs.

Collaboration

Share a link to co-edit in real time. No server, no account — peers connect directly via WebRTC.

  1. Click the share button in the top-right panel
  2. Share the generated link (app.openpencil.dev/share/<room-id>)
  3. Collaborators see your cursor, selection, and edits in real time
  4. Click a peer's avatar to follow their viewport

Why

Figma is a closed platform that actively fights programmatic access. Their MCP server is read-only. figma-use added full read/write automation via CDP — then Figma 126 killed CDP. Your design files are in a proprietary binary format that only their software can fully read. Your workflows break when they decide to ship a point release.

OpenPencil is the alternative: open source (MIT), reads .fig files natively, every operation is scriptable, and your data never leaves your machine.

See the roadmap for product direction and current Figma compatibility gaps.

Contributing

Setup

bun install
bun run dev:portless  # Web editor at https://open-pencil.localhost
bun run dev           # Direct Vite server at http://localhost:1420
bun run tauri dev     # Desktop app (requires Rust)

The first Portless run creates and trusts a local HTTPS certificate. Linked Git worktrees automatically receive branch-prefixed URLs such as https://fix-ui.open-pencil.localhost, so concurrent development servers do not compete for port 1420. Their development MCP bridges are exposed through matching sibling URLs such as https://fix-ui.mcp.open-pencil.localhost, with isolated TCP ports and runtime socket files. Run bunx portless doctor if local routing or certificate trust fails.

Alternatively, open the repository in any Dev Container-compatible tool. The container pins Bun, installs the workspace dependencies, and forwards the direct web editor on port 1420. Start it with bun run dev after the container is ready.

The Dev Container supports the web editor, packages, CLI, and automated checks. Native Tauri development still requires the host setup described below because desktop windows and platform WebView dependencies are not provided in the container.

Quality gates

Command Description
bun run check Lint + typecheck
bun run test E2E visual regression
bun run test:unit Unit tests
bun run format Code formatting

Project structure

packages/
  scene-graph/    @open-pencil/scene-graph — nodes, primitives, hit testing, copy/snap/undo
  pen/            @open-pencil/pen — Pencil document format helpers
  kiwi/           @open-pencil/kiwi — Kiwi runtime and low-level .fig container parsing
  fig/            @open-pencil/fig — .fig archives, SceneGraph conversion, instances, metadata
  core/           @open-pencil/core — editor engine, renderer, layout, tools, RPC, document I/O
  dom-css/        @open-pencil/dom-css — HTML/CSS/Tailwind to editable design documents
  vue/            @open-pencil/vue — headless Vue SDK
  cli/            @open-pencil/cli — headless CLI
  mcp/            @open-pencil/mcp — MCP server (stdio + HTTP)
  docs/           Documentation site (openpencil.dev)
src/              Vue app (editor shell, AI, collaboration, document I/O)
desktop/          Tauri v2 desktop app (Rust + config)
tests/            E2E, visual, engine, and integration tests

Tech stack

Layer Tech
Rendering Skia (CanvasKit WASM)
Layout Yoga WASM (flex + grid via fork)
UI Vue 3, Reka UI, Tailwind CSS 4
File format Kiwi binary + Zstd + ZIP
Collaboration Trystero (WebRTC P2P) + Yjs (CRDT)
Desktop Tauri v2
AI/MCP Multi-provider (Anthropic, OpenAI, Google AI, OpenRouter), MCP SDK, Hono

Desktop builds

Requires Rust and platform-specific prerequisites (Tauri v2 guide).

bun run tauri build

Acknowledgments

Thanks to @sld0Ant (Anton Soldatov) for creating and maintaining the documentation site.

License

OpenPencil is licensed under the MIT License.

Copyright (c) 2026 Danila Poyarkov and OpenPencil contributors.