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

Substantially exceeds the annotations: it discloses that whoami makes no network call and returns no secrets, that claim is one-way, and critically that logout only clears the locally saved key/profile while leaving it un-revoked on the relay. That side-effect scoping is exactly the behavioral detail an agent needs before mutating.

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 front-loaded sentence with a tight 'Agent identity and binding' opener followed by one clause per action. Dense but every clause carries information; no filler or repetition.

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-output-schema tool it covers all three actions, their side effects, and the key offline-vs-revoked distinction that an agent could otherwise get wrong. Nothing needed to call it correctly is missing.

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 description coverage is 100% and the description's action text duplicates the enum's own schema description nearly verbatim, so it adds little semantic value beyond the structured field. The `code` parameter is likewise already documented as required for claim. Baseline 3 applies when the schema does the heavy lifting.

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 the resource (agent identity/binding) and enumerates all three actions with a specific verb-plus-effect for each: whoami resolves relay URL/profile/key state, claim binds to a human, logout clears local state. It even distinguishes itself from the sibling `key` tool's revoke action.

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?

It gives clear per-action context and one explicit routing rule (use the `key` tool's revoke, not logout, to actually revoke a key). It does not spell out when each action is appropriate beyond that, but for a three-action identity tool the conditions are largely self-evident.

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