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CodePic

by abelce · remote · no sign-in to list tools · v1.0.0 · published by GitHub user abelce

AI agent draws editable hand-drawn diagrams (flowchart, ER, architecture) via MCP, not static images

Changes · 3

7 tools: 3 change things and 4 only read.

Scanned Oct 21, 2026

1 check matched something in the tool definitions. No finding is not a safety guarantee. How the checks work.

claude mcp add --transport http codepic https://codepic.cc/api/mcp/mcp --header 'Authorization: <your-authorization>'

Findings

Matches of fixed checks, with the text they matched.

1 info
  • The description is 2,413 characters long, over the 2,000 this check looks for.

    Matched text

    description ends: "...fill (e.g. #1565c0, #ef4444) → fontColor #ffffff; light fill → fontColor #111827"

    What this check looks for

Tools

Open a tool for its reasons and full description. Descriptions are the publisher's own words, shown as they are.

7 tools

Changes things 3Claude Code: ask
  • create_diagramCreate a custom CodePic hand-drawn style diagram by specifying nodes and edges.1 finding

    Why it is in this group

    • The name "create_diagram" says "create": a word for a change.

    Findings

    • Info

      The description is 2,413 characters long, over the 2,000 this check looks for.

      Matched text

      description ends: "...fill (e.g. #1565c0, #ef4444) → fontColor #ffffff; light fill → fontColor #111827"

      What this check looks for
    Description, as the server wrote it
    Create a custom CodePic hand-drawn style diagram by specifying nodes and edges. Requires API Key authentication. Returns a public view URL. **THIS IS THE DEFAULT TOOL FOR ANY USER-DESCRIBED DIAGRAM.** Whenever the user describes a diagram they want ("draw an A/B test flowchart", "帮我画一个登录流程", "a system architecture with a load balancer and 3 servers", etc.), build it here from their description. Do NOT fall back to `create_from_template` / `list_templates` unless the user explicitly asked for a template. When responding to the user, present the returned URL as a clickable markdown link (e.g. `[Open in CodePic →](URL)`) so the user can click it directly in their AI client (Cursor / Claude / etc.). **Container nesting (IMPORTANT — use whenever possible):** - Set `parentId` on a node to nest it inside another node. ANY node type can be a container. - The parent automatically becomes draggable-as-a-group and users can keep dropping elements into it. - Call `get_shape_catalog` with tag `container-capable` to choose among native structural containers and adaptive semantic shapes such as rectangles, circles, ellipses, diamonds, cylinders, and hexagons. - Parent bounds are expanded automatically using the selected shape's title and outline safe area. - Use absolute canvas coordinates for all nodes — child coordinates are auto-converted to parent-relative. - Set node `name`, `description`, and `tags` when later MCP/Agent reads need stable business semantics beyond visible text. - **Rule**: whenever 2+ nodes logically belong to the same module / component / region, create a container node first and set `parentId` on each child. **Design tips for beautiful diagrams:** - Use semantic types: `button-primary` for CTA buttons (auto blue), `diamond` for decisions - Pick a color palette and apply it consistently — light fill + darker stroke of the same hue: • Blue: fillColor #e3f2fd / #bbdefb, strokeColor #1565c0, fontColor #1565c0 (or #ffffff on dark fill) • Green: fillColor #e8f5e9 / #c8e6c9, strokeColor #2e7d32, fontColor #1b5e20 • Purple: fillColor #f3e5f5 / #e1bee7, strokeColor #6a1b9a, fontColor #4a148c • Neutral: fillColor #f8fafc / #f1f5f9, strokeColor #475569, fontColor #1e293b - Each semantic group (decisions, processes, I/O) should share a fill color to create visual hierarchy - Dark fill (e.g. #1565c0, #ef4444) → fontColor #ffffff; light fill → fontColor #111827
  • create_from_templateCreate a new CodePic diagram from a predefined template.No findings

    Why it is in this group

    • The name "create_from_template" says "create": a word for a change.
    Description, as the server wrote it
    Create a new CodePic diagram from a predefined template. Requires API Key authentication. Returns a public view URL and edit URL. **STRICT USAGE RULE — READ BEFORE CALLING:** Only call this tool when the user has **explicitly** asked to use a template. Explicit signals include phrases like: "use a template", "from template", "用模板", "从模板创建", "list templates and pick one", or the user directly naming/selecting a template slug. If the user merely describes a diagram they want (e.g. "draw an A/B test flowchart", "帮我画一个登录流程", "给我做一个系统架构图"), **DO NOT** call this tool. Call `create_diagram` instead and build the diagram from the user's description. Never silently substitute a template for a described diagram — the user will get a generic result that does not match what they asked for. When responding to the user, present the returned URL as a clickable markdown link (e.g. `[Open in CodePic →](URL)`) so the user can click it directly in their AI client (Cursor / Claude / etc.).
  • update_diagramUpdate an existing CodePic diagram.No findings

    Why it is in this group

    • The name "update_diagram" says "update": a word for a change.
    Description, as the server wrote it
    Update an existing CodePic diagram. You can rename it, replace all nodes/edges, or add/remove individual nodes and edges. Requires API Key authentication. When responding to the user, present the returned URL as a clickable markdown link (e.g. `[Open in CodePic →](URL)`) so the user can click it directly in their AI client (Cursor / Claude / etc.).
Only reads 4Claude Code: allow
  • get_diagramFetch the current state of an existing CodePic diagram.No findings

    Why it is in this group

    • The name "get_diagram" says "get": a word for reading.
    Description, as the server wrote it
    Fetch the current state of an existing CodePic diagram. Returns a compact summary of all elements with their IDs, types, positions, and parent-child relationships. Use this before update_diagram when you need to: add nested children to existing containers, make targeted edits to specific elements, or understand the current structure. Requires API Key authentication.
  • get_shape_catalogReturn compact machine-readable shape metadata for planning a diagram: semantic tags, geometry family, container support, recommended padding, default size, and MCP availability.No findings

    Why it is in this group

    • The name "get_shape_catalog" says "get": a word for reading.
    Description, as the server wrote it
    Return compact machine-readable shape metadata for planning a diagram: semantic tags, geometry family, container support, recommended padding, default size, and MCP availability. Use this before create_diagram when choosing shapes or containers. Unlike get_shape_docs, this tool is concise and filterable.
  • get_shape_docsReturn the full CodePic shape reference — all element types, their fields, data payloads, and JSON examples.No findings

    Why it is in this group

    • The name "get_shape_docs" says "get": a word for reading.
    Description, as the server wrote it
    Return the full CodePic shape reference — all element types, their fields, data payloads, and JSON examples. Call get_shape_catalog first for concise shape selection and container capabilities; use this tool when you need complete fields or type-specific data (e.g. select options, triangle direction, callout tail). No authentication required.
  • list_templatesList all available CodePic diagram templates.No findings

    Why it is in this group

    • The name "list_templates" says "list": a word for reading.
    Description, as the server wrote it
    List all available CodePic diagram templates. Use this ONLY when the user has explicitly asked to browse, list, or pick from templates (e.g. "show me templates", "列出模板"). Do NOT call this as a preparatory step when the user just described a diagram they want — in that case go straight to `create_diagram`. Discovering slugs here is only meaningful before a user-confirmed `create_from_template` call.

This is not a safety rating, and no finding is not a safety guarantee. The groups and findings come from fixed checks of the tool definitions the server returned on the date shown, not from its code or what it does when called. How the checks work.

Install

Pinned to version 1.0.0. Values in angle brackets are yours to fill in.

claude mcp add --transport http codepic https://codepic.cc/api/mcp/mcp --header 'Authorization: <your-authorization>'

Run in a terminal.

Claude Code permissions

Allow the reads, ask before a change, deny the deletes. Paste into .claude/settings.json.

.claude/settings.json
{
  "permissions": {
    "allow": [
      "mcp__codepic__get_shape_docs",
      "mcp__codepic__get_shape_catalog",
      "mcp__codepic__list_templates",
      "mcp__codepic__get_diagram"
    ],
    "ask": [
      "mcp__codepic__create_from_template",
      "mcp__codepic__create_diagram",
      "mcp__codepic__update_diagram"
    ],
    "deny": []
  }
}

Tools that only read are allowed, tools that change things ask first, tools that delete or cancel are denied. It assumes the server is installed as codepic. Review it before you use it.