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

Annotations already declare readOnlyHint=false, destructiveHint=true, and idempotentHint=true, so the safety profile is covered. The description adds genuinely new behavioral context: it is a partial update where only supplied fields are sent and everything else is preserved, plus the underlying PUT endpoint – context an agent would not get from the annotations alone.

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 very short sentences, front-loaded with the operation type and its most important semantic constraint. No filler.

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 an 8-parameter mutation tool with rich annotations and no output schema, the description covers the key behavioral facts: write operation, partial-update semantics, and endpoint. It does not discuss the destructive/replace behavior of fields like 'background' or error/return shape, leaving a small gap.

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 per-field meanings are already documented. The description still adds semantic value by clarifying the partial-update contract ('only the fields you give are sent; the rest stays'), which the schema's property list alone does not establish.

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: 'change fields of a person', with a 'WRITE:' prefix that separates it from the read-oriented siblings (get_person, list_people). It does not explicitly name a sibling to distinguish from create_person or update_company, so it stops short of the top score.

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?

Usage is only implied by the word 'change' – an agent can infer this is for modifying an existing person rather than creating one. There is no explicit when-to-use/when-not guidance or reference to a preferred alternative.

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