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

Annotations declare readOnlyHint=true, openWorldHint=true, idempotentHint=true, and destructiveHint=false, establishing a safe, read-only profile. The description adds crucial behavioral context beyond annotations: it builds drafts only from the user's own CV and the advert, leaves unknown details as bracketed prompts, and states that nothing is sent or stored. This is exactly the kind of operational detail an agent needs.

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?

Front-loaded with the purpose and example triggers, then quickly moves to construction rules and constraints. Every sentence adds value: no repetition of schema details, no filler. The structure is dense and informative.

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?

With 15 parameters, no required fields, and no output schema, the description must tell the agent how to call it and what to expect. It does: the draft is generated from provided materials, missing info becomes placeholders, and the tool does not apply or store anything. This covers all the critical gaps for a zero-required-parameter tool.

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 coverage is 100%, so the baseline is 3. The description goes further by explaining how parameters are used: the CV lines and advert are the only source material, missing personal details become [bracketed] prompts, and common questions are used if 'questions' is omitted. This adds meaningful semantics beyond the schema's field descriptions.

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 specific verbs and resources: drafting a cover letter and application answers. The tool name and description are aligned, and it's clearly distinguished from siblings like write_job_advert (writing for employers) and match_cv (matching, not drafting). The description includes example invocations that pin down the exact use case.

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 gives direct invocation examples ('write my cover letter for this job', 'help me answer these application questions') that tell the agent exactly when to use it. However, it doesn't explicitly compare to alternatives like apply_kit or match_cv, leaving some ambiguity about when to prefer one over the other.

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