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

Annotations only cover readOnlyHint=true, so the description carries the rest and does add real context: a 'failed' status means the error field is the coach's rejection reason and must be treated as a hard constraint. It does not disclose ordering/limit behavior or what a non-failed run contains, but the added semantic guidance is genuinely beyond annotations.

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?

Three short sentences, front-loaded with the action and followed by the interpretation rule and the integration constraint. No filler or restatement of the tool name.

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?

There is no output schema, so the description usefully explains the one output field that drives behavior (error on failed runs). What remains thin is the limit/pagination behavior and the shape of successful runs, but the critical decision-making context is present.

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 0% for two parameters (clientId, limit), so the description is the only place to document them — and it says nothing about clientId's format or limit's default (5) and maximum (20). Neither parameter is explained anywhere, which is a real gap for a 0%-coverage schema.

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?

States a specific verb and resource: reading a client's past AI Coach runs. The scope is clear and the description also frames why the data matters, though it does not differentiate itself from any near-sibling (none exists in the list, so differentiation is less relevant).

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?

Explicitly says when to call it ('before building or adjusting their plan') and names the two downstream tools it must precede (create_workout_plan/create_diet_plan). It also gives the interpretation rule for failed runs, removing all inference.

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