Things App MCP

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

Annotations provide openWorldHint=true, indicating the tool can handle unknown parameters, but the description adds minimal behavioral context beyond stating authentication requirements. It doesn't disclose mutation effects, rate limits, or other behavioral traits. However, it doesn't contradict annotations, so it earns a baseline score for adding some value without rich disclosure.

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 a single, efficient sentence that front-loads the core purpose and key requirements. It avoids unnecessary words, though it could be slightly more structured by separating purpose from prerequisites. Overall, it's appropriately sized with zero waste.

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?

Given the tool's complexity (18 parameters, mutation operation) and lack of output schema, the description is minimally adequate. It covers authentication and ID requirements but doesn't explain update behaviors, side effects, or return values. With annotations providing only openWorldHint, more context on mutation impact would improve completeness for this non-trivial tool.

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?

With 100% schema description coverage, the input schema fully documents all 18 parameters. The description adds no parameter-specific information beyond mentioning 'project ID' and 'auth-token' in general terms. This meets the baseline of 3 since the schema does the heavy lifting, but the description doesn't enhance understanding of parameter semantics.

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 action ('Update an existing project') and resource ('in Things'), which provides a specific verb+resource combination. However, it doesn't distinguish this tool from its sibling 'update-todo' or explain what differentiates project updates from todo updates, missing full sibling differentiation.

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 description mentions that the tool 'Requires the project ID and your Things auth-token,' which provides basic prerequisites but no guidance on when to use this tool versus alternatives like 'update-todo' or other project-related tools. There's no explicit when/when-not usage context or named alternatives.

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