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

Annotations already declare readOnlyHint=true and openWorldHint=false, but the description adds something they cannot: the call requires a bearer token with scope 'read'. That auth prerequisite is exactly the kind of extra behavioral context that matters before invocation. It stops short of describing the full profile payload.

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?

Two tightly bracketed clauses with no filler, and the core statement ('Your profile') is front-loaded. The dense parenthetical style is efficient but slightly terse to parse compared with plain prose.

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 a zero-param identity tool with no output schema, the description covers the resource returned, one meaningful status value, and the auth requirement. It omits the rest of the profile shape, which stops it short of fully self-contained.

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?

The tool takes zero parameters, so the schema-baseline of 4 applies. The description does not invent parameter details but does surface the 'status' field's meaning in the returned profile, which is a useful semantic hint.

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?

The description names a concrete resource ('Your profile'), which immediately separates it from sibling lookups like get_agent or agents_by_tag by signaling the call is scoped to the caller. It is clear enough to act on, though it never explicitly contrasts itself with those siblings.

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?

'status pending = finish signup first' names both the triggering condition and the alternative action, effectively routing the agent to the finish_signup sibling. There is no explicit when-not guidance, but the conditional is actionable.

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