Who am I

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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive behavior, so the safety profile is covered. The description adds the useful detail that the result includes name and groups, but it does not go beyond that into edge cases like unauthenticated responses, which would have added further transparency.

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, tight sentence with no filler. The core action, output content, and purpose are all front-loaded, and every word earns its place.

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 parameterless, read-only identity check with comprehensive annotations, the description covers everything an agent needs: what it does, what it returns, and why to call it. There is no missing information that would hinder correct invocation.

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, and the schema coverage is essentially complete. The description implies no input is needed, which matches the empty schema; the baseline of 4 applies because there is nothing for parameter documentation to explain.

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 states a specific action ('Return') and resource ('authenticated user') plus the precise content ('name and groups'). It clearly differentiates from all sibling tools, which operate on projects, resources, logs, or events rather than the caller's identity.

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 clearly frames the tool's use case: confirm which identity the server is using. It does not explicitly list exclusions or alternatives, but the sibling tools are sufficiently different that the intended context is unambiguous.

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