Doop vs Pencil: Features, Pricing & Which Is Better (2026)
A side-by-side comparison of Doop and Pencil — features, pricing, and ideal use cases — to help you decide which AI tool fits your workflow.
Doop
Kevin Goedecke
Open-source infinite design canvas where humans and AI agents design together live, with agents joining through a built-in MCP server.
Key features
- Agent-Native MCP Canvas: Agents connect over an HTTP MCP endpoint with a single command and one browser OAuth approval, then edit the canvas as you, attributed and accountable, with no API keys handed over.
- Streaming Frames: Every section an agent writes renders on the canvas the moment it lands, so you watch the design arrive rather than waiting on a spinner.
- Comments as Tasks: A note left anywhere on the canvas becomes a task the right agent picks up, works on, and replies to with a screenshot, turning feedback directly into the backlog.
- Agent Self-Review: A built-in headless renderer gives agents screenshots of their own frames so they judge fit, spacing and contrast like a senior designer and correct issues before handoff.
- Shared Canvas Memory: Tasks, decisions and comments live on the canvas rather than in one agent's context, so any agent that joins later plugs into the same state and continues.
- Learned Taste Profile: Casual feedback such as 'rounder corners' or 'keep it to the blue' is distilled into a persistent taste profile applied to every new frame and inherited by every agent.
- Live Export URLs: Each frame is a URL that can be embedded in a doc, a post or an og:image and re-renders whenever the design changes, so shared assets never go stale.
- Reference and URL Import: Paste screenshots to have agents distill palette, type and mood into a written brief, or paste a public URL to land an editable snapshot of your existing page on the canvas for side-by-side variants.
Best for
- Agent-Assisted Landing Pages: Steering Claude Code or Codex through hero, pricing and footer frames on one canvas and watching each render live.
- Design Review Loops: Leaving contrast or spacing notes on a frame and letting an agent apply the fix and return a screenshot without a synchronous handoff.
- Redesign Comparison: Importing an existing public page as an editable snapshot so agent-generated variants sit next to the original instead of replacing it blind.
- Team Design Sessions: Multiple people and multiple agents working the same canvas, each seeing what the others' agents are doing in real time.
- Style Consistency: Building a canvas taste profile once so every subsequent frame and every new agent inherits the same corner radius, palette and type decisions.
- Always-Fresh Shared Assets: Embedding live frame URLs in documentation or social posts so the shared image updates automatically when the design changes.
Pencil
Pencil (Pencil Works)
In-IDE design canvas that lets engineers design UI and convert designs directly into code to speed development.
Key features
- In-IDE Design Canvas: Provides a visual design canvas embedded inside developers' IDEs so users can create and edit UI designs without context switching to external design apps.
- Design-to-Code Export: Converts designs into code-friendly artifacts or components (land in code) to reduce manual implementation and speed delivery of production UI.
- Local MCP Server & Discovery: Runs a local MCP-style service that writes config (e.g., ~/.claude.json) so external tools and agents can discover Pencil, read its port/command, and integrate programmatically.
- Auto-Configuration & Port Sync: Supports auto-setup and auto-sync behaviors (project or global scope) so integrations (like OpenCode) automatically add Pencil to their configs and update ports when Pencil restarts.
- Project-Scoped Integration: Can be configured per-project or globally, allowing teams to make Pencil available only within specific repositories or across all projects for consistent workflows.
- Tooling & CLI Support: Exposes status, setup, and sync actions for partner tools and agent plugins (e.g., pencil_status, pencil_setup, pencil_sync) to manage connectivity and lifecycle programmatically.
- Canvas-based UI design embedded into developer workflows/IDEs
- Design-to-code export so visual designs can be converted into code artifacts
- Runs a local MCP/config server and writes runtime config to a file (e.g., ~/.claude.json) for tooling integrations
- Integration plugins (example: OpenCode pencil-sync) that auto-setup Pencil in project/global configs and auto-sync ports after restarts
- CLI/tools for status, setup and sync (pencil_status, pencil_setup, pencil_sync) to manage Pencil integration lifecycle
- Support for project or global scope configuration (config added to ~/.config/opencode/opencode.jsonc or ./opencode.json)
- Automatic port/config backup and validation when updating third-party tool configs
Best for
- IDE-native UI Implementation: Designers and engineers create UI layouts directly inside an IDE and export components to the codebase, eliminating design handoffs and manual translation.
- Agent-enabled Code Generation: Integrate with developer agents or automation (via Pencil's MCP config) to let bots generate, update, or wire up UI code from canvas designs automatically.
- Project-scoped Tooling Integration: Add Pencil to a single project's config to enable team members to access the same design-canvas tooling and keep design artifacts synchronized with that repository.
- Auto-recovery After Restarts: Use automatic port-sync and setup tools so external tooling (like OpenCode) recovers connectivity after Pencil restarts without manual reconfiguration.
- Rapid Prototyping and Iteration: Quickly prototype UI ideas inside the IDE, iterate in-context with code, and validate implementations faster by seeing designs translate to code artifacts immediately.
- Cross-tool Workflow Automation: Connect Pencil with CI, linters, or component libraries via its MCP endpoint to automate tasks like component registration, export, or style enforcement from designs.
- Embed visual design work directly inside developers' IDEs to reduce context switching
- Automatically export or convert canvas designs into code components or project assets
- Auto-configure developer tools and agents to use the locally running Pencil service
- Keep IDE/tooling configurations in sync when Pencil restarts or changes port
- Integrate Pencil with automation agents or local development frameworks to enable programmatic access to designs