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

Annotations already cover readOnly and idempotent, so the safety bar is low; the description still adds real behavioral value by enumerating the returned field set, asserting location is never included (even when cloaked), specifying case-insensitive matching, and documenting the player_not_found error path.

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 core action, then fields, then exclusions, then alternatives. The parenthetical field list is long but earns its place as a substitute for an absent output schema; only minor redundancy in 'public profile ... the website shows'.

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 no output schema, the description fully compensates by listing returned fields, stating the privacy guarantee (no location), noting match behavior, and covering the not-found case. An agent has everything needed to call and interpret it correctly.

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 parameters are already documented. The description's only parameter-related note (case-insensitivity) merely restates the schema's own 'case-insensitive' description, adding no new semantics beyond the 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+resource ('look up another pilot's public profile by username') and enumerates exactly what is returned. It distinguishes itself from siblings like get_status and faction_info by scoping to 'another pilot' and noting that location data is never present.

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 clear context (look up by username) and routes the agent to alternatives for the adjacent task of locating a pilot ('look around with get_nearby or scan'). It does not explicitly say when *not* to use this profile lookup versus, e.g., viewing one's own profile, but the operating condition is clear.

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