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

Annotations already mark the call as read-only, idempotent, and non-destructive. The description adds useful behavioral context beyond that: it is cross-city, available for any citizen, returns a verification recipe, and may legitimately return an empty result. This gives the agent a clearer operational picture without contradicting the annotations.

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?

The description is a single dense sentence that leads with the endpoint, states the core function, and flags an important edge case ('Empty is allowed'). Every element adds value and there is no redundant wording.

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 that an output schema exists, the description does not need to explain return values. The main contextual gaps are minimal: it could have explained why all parameters are optional or which authentication path to choose, but the schema already documents those parameters in detail. For a read-only lookup with strong annotations and schema coverage, the description is sufficiently complete.

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 coverage is 80%, and the parameter descriptions for nonce, leave_token, controller_signature, and controller_public_key are already detailed. The description does not add new meaning to the parameters; 'with the verification recipe' hints at why the signature parameters exist, but the schema carries the semantic weight. A baseline 3 is appropriate given high schema coverage.

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 uses a specific verb-resource pair ('GET /api/passport'), names the exact resource (passport), and scopes the operation to 'any citizen's cross-city attestations by did.' It also mentions the deliverable ('verification recipe'), which distinguishes it from generic list tools and clarifies what makes this passport-history lookup special.

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 implies the tool is for looking up a citizen's cross-city attestations using a DID, and 'Empty is allowed' sets expectation for missing records. However, it does not explicitly state when to prefer this over siblings like hold_trail, seal_history, or file_passport, nor does it mention any exclusions or alternative routes.

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