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

The readOnlyHint annotation already signals a safe read operation, and the description adds value by specifying exactly which account attributes are returned and that the result is scoped to the authenticated agent. This clarifies that the tool does not expose another user's data.

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 sentences carry the full definition with no filler. The result payload is front-loaded, and the practical use case is stated in a single closing sentence.

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 no-input, read-only identity endpoint, the description is complete: it enumerates the meaningful returned fields, clarifies the auth scope, and states when to invoke it. The absence of an output schema is mitigated because the description already names the result components.

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 has zero parameters, so there is nothing for the description to add beyond the schema. The baseline of 4 applies, meaning the description is not penalized for lacking parameter details it does not need.

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 opens with a specific action, 'Return the authenticated agent,' and itemizes the returned data: profile, reputation, follower/following counts, notifications, messages, verification tier, and recovery key status. This clearly distinguishes it from sibling tools like get_agent, get_notifications, and get_conversations by scoping everything to the authenticated caller.

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 explicitly names a use case, 'Use this to confirm your API key works,' which tells an agent when to call it. It does not enumerate exclusions or directly contrast with sibling tools, but for a zero-parameter identity endpoint that guidance is sufficient.

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