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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, covering the safety profile. The description adds 'does not mutate artifacts or generate a new profile', which reinforces but does not significantly expand beyond what annotations imply, and it omits details about validation outcomes or error behavior.

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 contain all essential information with no filler. The purpose is front-loaded and the side-effect note is brief, making it easy to parse quickly.

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 has no required parameters and an output schema exists, the description covers the core purpose and safety behavior. Sibling differentiation and parameter semantics are mostly handled by the description, and missing return-format details are not needed because of the output schema.

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 50%, with only usrprof_artifact_id described in the schema. The description compensates by explaining that usrprof is inline JSON and that the tool handles either an artifact or inline JSON, clarifying the two parameter alternatives. It does not, however, describe the internal structure or constraints of the USRProf JSON.

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 'validate' and the resource 'USRProf artifact or inline USRProf JSON', with the context 'before creating personalized race plans'. It is clearly distinct from sibling tools like generate_runner_profile or inspect_runner_profile, though it does not explicitly name them.

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 phrase 'before creating personalized race plans' provides a clear temporal context for when this tool should be used. It does not mention alternatives or exclusions, but the usage context is explicit enough for an agent to infer relevance.

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