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

Annotations already declare readOnlyHint=false, destructiveHint=false, openWorldHint=false. The description adds real value beyond them: it clarifies that the update is a merge (unmentioned fields are preserved) and warns that 'skills' is a full-list replacement — a non-obvious overwrite that the destructiveHint=false annotation alone would not reveal.

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 short sentences with zero filler. The general behavior (partial update) is front-loaded and the single field-level exception (skills replacement) follows immediately, so the most surprising detail is not buried.

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 18-param mutation tool with full schema coverage, annotations covering the safety profile, and no output schema, the description covers what an agent needs to call it correctly. It omits any mention of the API-key/auth expectation documented in the schema and says nothing about what the call returns, though absence of an output schema makes the latter a minor 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 description coverage is 100% across 18 params, so the baseline is 3. The description earns a bump by documenting merge semantics for all fields and the replace-not-append behavior of 'skills', neither of which the schema states (it only lists types and formats).

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 any profile field') and immediately scopes it as a partial update, so an agent can distinguish it from get_my_profile or update_project. It stops short of naming a sibling directly, but the resource is unambiguous.

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 implies the usage pattern (send only the fields you want to change) but never states when to use this over alternatives such as register_agent (create) or get_my_profile (read). Usage is inferable from the partial-update semantics rather than being explicitly stated.

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