excalidraw-editor-mcp

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Save Excalidraw canvas

push_canvas

Save the current Excalidraw canvas document to its bound path, using a compare-and-swap mechanism with a base revision and mutation ID to prevent conflicts.

Instructions

Saves the bound standard document with compare-and-swap.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "canvasPath": "<canvasPath>",
      "baseRevision": "<baseRevision>",
      "mutationId": "<mutationId>",
      "document": "<document>"
    },
    "name": "push_canvas"
  }
}

Input Schema

Name	Required	Description
`document`	Yes
`canvasPath`	Yes	Full workspace-relative canvas path under projectPath, for example designs/m3/main.excalidraw. Never pass only main.excalidraw.
`mutationId`	Yes
`baseRevision`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.0.0Sep 7, 2026

TDQS

C2.8/5.0

Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description alone must disclose side effects and failure behavior. It mentions compare-and-swap, but does not explain what happens on revision mismatch, whether the operation creates or updates, or what other side effects occur.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single focused sentence with no filler and front-loaded action. It is maximally concise, even though that brevity reduces clarity in other dimensions.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a complex CAS write tool with a nested document schema and no output schema or annotations, this one-line description is not complete. It omits return behavior, error conditions, and revision handling details.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters2/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Only canvasPath has a schema description; baseRevision, mutationId, and document are undocumented. The compare-and-swap phrase hints at baseRevision and mutationId, but the description does not explain their roles, idempotency, or the expected document structure.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The title and description state a clear action: saving the bound standard document with compare-and-swap. The CAS mention helps distinguish it from ordinary save or copy operations, though 'bound standard document' is somewhat vague.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description gives no guidance on when to use push_canvas versus siblings such as save_canvas_copy, replace_canvas, pull_canvas, or apply_canvas_changes. The compare-and-swap hint is not expanded into concrete selection criteria.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.