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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, openWorld), so the bar is lower. The description still adds useful disclosure about data scope, enumerating what the payload contains and explicitly stating 'No contact details', which is meaningful privacy/behavioral context an agent cannot infer from annotations.

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 dense sentence with the identifier rule front-loaded followed by the return payload. It is on the long side, but each clause (username source, rank format, field list, no-contact caveat) carries distinct information rather than padding.

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?

There is no output schema, so the description takes on the burden of describing the return shape and does so thoroughly: About text, skill test ranks with N of M and top X%, headline, city, education, talents, experience, canonical URL. Combined with the identifier explanation, an agent has everything needed to call and interpret it.

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% and the schema already names the parameter, but the description adds real meaning by pinning username to the URL fragment 'the part after /y/ in https://www.youth4work.com/y/{username}', which reduces ambiguity about the identifier's format.

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: fetch the public profile of one member identified by username. It also scopes the resource as public-only and explains the username's origin, which lets an agent separate this from siblings like search_talent or get_college.

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: this retrieves exactly one member and the username is the segment after /y/ in the profile URL. It does not explicitly say when to use this versus search_talent for discovery-style lookups, so routing guidance is implied rather than stated.

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