whoami

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

No annotations provided, but description indicates a read-only operation returning profile info. It does not mention side effects, but with zero parameters and output schema, the behavior is well-understood. The description is clear enough for a simple tool.

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 short sentences with no fluff. The first sentence states purpose, the second provides usage context. Highly efficient.

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?

Given zero parameters and an output schema, the description is complete. It explains what the tool does and when to use it. No missing information for effective use.

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 has no parameters and 100% coverage, so description need not add parameter info. It correctly omits parameter details since there are none.

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?

Clearly states the tool returns the user profile for the current API key. The verb 'return' and resource 'user profile' are specific. However, it does not differentiate from siblings since no other tool returns user info.

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?

Explicitly states it's useful as a sanity check after configuring a new key, providing clear context for when to use it. No alternatives or exclusions are mentioned, but given no other sibling does this, it's sufficient.

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