update-body-measurement

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

Reveals key behaviors: omitted fields become null, 404 for nonexistent date. No annotation support, so carries full burden; still informative though missing auth/rate limits.

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?

Two sentences: first states action, second details side effects and error condition. No redundant 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?

Covers essential: purpose, overwrite semantics, 404. No output schema but mutation tools typically need less. Sufficient for a tool with 18 params.

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 covers all parameters with units. Description adds value beyond schema by explaining global overwrite behavior and date existence requirement.

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?

Explicitly states update action on an existing body measurement entry, distinguishing from create/get siblings. Adds unique behaviors: overwrite and 404 on missing date.

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?

Clear about overwrite behavior and 404 error, guiding when to call. Lacks explicit alternative (e.g., use create-body-measurement if new date), but implied.

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