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

Annotations only give destructiveHint=true, so the description earns credit by disclosing that the operation is reversible and, importantly, that it runs no verification. It stops short of explaining what is overwritten or how partial updates behave, and 'reversible' sits in mild tension with destructiveHint=true rather than fully contradicting it (something can be destructive to old values yet undoable).

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?

One tight sentence with the purpose front-loaded and a single parenthetical for behavioral caveats and endpoint. Nothing is wasted.

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?

Adequate but with clear gaps: for a mutation tool with nested objects and no output schema, the description does not clarify partial-vs-replace update semantics or what the response returns. The rich schema covers the inputs, so the missing pieces are secondary, keeping this at minimum-viable-plus.

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 100%, so all eight parameters are already documented and the baseline is 3. The description adds no field-level meaning beyond restating the applicant_id path parameter, so the schema does the heavy lifting.

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 ('Updates an applicant's details') that is plainly distinct from the create/get/list siblings, and pins it to the PUT /applicants/{applicant_id} endpoint. It is clear but does not explicitly name an alternative the way a top-tier definition would.

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?

No explicit when-to-use / when-not-to-use or named alternatives; the guidance is implied by the verb. It does add one useful scoping cue ('runs no verification'), telling the agent this call won't trigger a check, which is real usage context but not a full decision rule.

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