Excalidraw MCP Server

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

With no annotations provided, the description carries full burden and does well by disclosing return values (elements, state, version, session ID), multi-session support behavior, and default session usage. It doesn't mention rate limits, authentication needs, or error conditions, but covers core behavioral aspects adequately.

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

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

The description is efficiently structured with clear sections (Returns, Usage scenarios, Multi-session support), front-loaded with the core purpose, and every sentence adds value without redundancy. It's appropriately sized for the tool's complexity.

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

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

For a read-only tool with 1 parameter and no output schema, the description is mostly complete—it explains purpose, usage, returns, and behavior. However, without annotations or output schema, it could benefit from mentioning response format details or error handling, leaving minor gaps.

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

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

Schema description coverage is 100%, so the schema already documents the sessionId parameter. The description adds marginal value by explaining 'If not provided, uses default session,' which slightly elaborates beyond the schema's 'If not provided, uses default session.' Baseline 3 is appropriate when schema does the heavy lifting.

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

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

The description clearly states the verb 'retrieve' and resource 'complete information about the current diagram scene,' distinguishing it from siblings like list_sessions (lists sessions) or update_element (modifies elements). It specifies it returns comprehensive scene data rather than partial information.

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

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

The 'Usage scenarios' section provides clear context for when to use this tool (viewing content, analyzing structure, obtaining IDs for updates/deletion). However, it doesn't explicitly mention when NOT to use it or name specific alternatives like list_sessions for session overviews.

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