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

Beyond the read-only/idempotent annotations, it discloses the 404 error conditions and explains why a protected account yields 404 (posts and connections visible only to approved accounts). It also states the billing model, including the extra charge when a numeric id is used, which annotations cannot express.

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 return contents, then error behavior, then cost, which is a sensible ordering for an agent reading top-down. It is fairly dense and the protected-account clause reads like an inline aside, but no sentence is pure 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?

With no output schema, the description compensates by enumerating exactly which fields come back: country attribution, connection to X, username-change count, and verification. Combined with the error conditions and cost model, an agent has everything needed to call it and interpret the result.

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 accepted forms of `user` (handle, numeric id, profile URL) are already documented in the schema and not repeated. The description's only real parameter insight is the billing consequence of passing a numeric id, which is a marginal addition over the schema.

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 (get) and a clearly bounded resource: the 'About this account' panel contents, enumerated as country attribution, connection to X, username-change count, and identity verification. This distinguishes it from get_x_user's general profile, though the description never names that sibling explicitly, leaving the distinction implicit 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?

'Useful for judging whether an account is what it claims to be' gives a concrete decision context for calling it, which is more than most entries provide. It falls short of a full when/when-not rule because it never tells the agent to prefer get_x_user for ordinary profile data or to skip this call when authenticity is not in question.

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