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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so the safety profile is covered. The description adds that the response includes 'full details and relationships', which hints at response shape, but says nothing about behavior on missing IDs, permission requirements, or cost of expanding relationships (which the schema covers only for the include param).

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?

A single sentence with the key constraint ('by ID') and the payoff ('full details and relationships') front-loaded. Nothing extraneous.

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 an output schema present, annotations covering safety, and full parameter documentation, the description does not need to explain return values. It is nearly complete for a simple getter; the only missing piece is guidance for not-found or ID-resolution cases.

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 both the id and include parameters are already documented, including the 25-record truncation note. The description adds only the loose phrase 'with full details and relationships', which does not clarify the include semantics beyond the schema baseline.

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 ('Get a single person by ID') plus a scope note ('full details and relationships'), which distinguishes it from the sibling list-people-tool. It never names the sibling explicitly, so the differentiation is implied rather than stated.

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?

'By ID' implies the caller must already have an identifier, which implicitly separates this from list/search flows. However, there is no explicit guidance on when to prefer list-people-tool versus this tool, nor on what to do when the ID is unknown.

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