Things MCP Server

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

With no annotations provided, the description carries full burden for behavioral disclosure. While 'Create' implies a write operation, it doesn't specify permissions needed, whether todos are immediately saved or require confirmation, what happens on duplicate titles, or error conditions. The description mentions parameter precedence ('heading_id takes precedence over heading') which adds some behavioral context, but overall leaves significant gaps for a mutation tool.

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 appropriately sized but not optimally structured. The initial sentence clearly states the purpose, but the parameter documentation could be better organized. While each parameter explanation is concise, the list format is functional but not particularly elegant. Every sentence earns its place, but the structure could be more front-loaded with critical information.

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 (10 parameters, mutation operation) and the presence of an output schema (which handles return values), the description is moderately complete. It excels at parameter documentation but lacks behavioral context for a mutation tool with no annotations. The combination of good parameter semantics but missing behavioral guidance results in an incomplete picture for proper tool invocation.

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 0% schema description coverage, the description provides excellent parameter semantics that fully compensate. It explains all 10 parameters with clear meanings, including special formats for 'when' (today, tomorrow, evening, anytime, someday, or YYYY-MM-DD) and 'deadline' (YYYY-MM-DD), plus important behavioral details like precedence rules for heading_id vs heading. This goes well beyond what the bare schema provides.

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 ('Create') and resource ('new todo in Things'), making the purpose specific and understandable. However, it doesn't explicitly differentiate from sibling tools like 'add_project' or 'update_todo', which would require mentioning this is specifically for todos (not projects) and creates new items (not updates existing ones).

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 provides no guidance on when to use this tool versus alternatives. It doesn't mention when to choose 'add_todo' over 'add_project' for different item types, or when to use 'update_todo' instead for modifying existing todos. There's also no mention of prerequisites or contextual constraints for creating todos.

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