People Search

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

Annotations already declare the safety profile (read-only, idempotent, open-world, non-destructive), so the bar is lower, yet the description still adds real value: relevance-ranked ordering, the three data sources searched, and the five fields returned. That return-shape disclosure matters especially since there is no output schema.

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 sentences with zero filler, ordered purpose → returns → alternative routing, so the most decision-relevant information leads. Each sentence carries a distinct load.

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?

For a two-parameter, flat, read-only search with complete schema coverage and full annotations, the description supplies the only missing pieces: the result shape (compensating for the absent output schema) and the sibling boundary. Nothing an agent needs to call it correctly is absent.

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 both `query` and `count` (with its default/max bounds) are already fully documented in the schema. The description adds only the framing that `query` covers name, email, or company, which duplicates rather than extends the schema's own wording. Baseline 3 is correct.

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 ('relevance-ranked search') plus the exact resource scope (personal contacts, organisation directory, recent communications) and the backing API. The named return fields let an agent confirm this is a people-lookup tool distinct from search-emails or list-events without opening any schema.

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?

Gives concrete triggering intents ('who is X?', 'who do I email about Y?') and explicitly routes the personal-contact-store-only case to a named sibling with its exact action argument. Nothing about when-to-use is left to inference.

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