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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so safety is covered. The description still adds non-obvious behavior: house probes are excluded from results and an empty result is valid rather than an error. 'No proof' usefully clarifies that the optional proof params need not be supplied for a listing.

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?

Five short, front-loaded sentences with zero filler. The core purpose leads, then the alternative, then the two edge-case guarantees, then the safety note.

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 zero-required-param list tool with an output schema and full annotation coverage, the description supplies everything relevant: purpose, sibling routing, result exclusions, empty-result semantics, and auth posture. Nothing an agent needs 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 coverage is 100%, so all four parameters (nonce, leave_token, controller_signature, controller_public_key) are already documented in the schema. The description's 'no proof' note implicitly frames these as optional, but adds no format or usage detail beyond that. Baseline 3 is appropriate 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?

States a specific verb and resource ('Lists all published citizen cards') and frames it as the capability board. It explicitly distinguishes itself from the sibling card_get ('for one card use card_get') and adds a scope exclusion ('House probes are not listed'), so an agent can route without opening either schema.

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?

Gives the selection condition ('find a citizen by what they say they do') and names the alternative for the single-card case. 'House probes are not listed' and 'Empty is allowed' set explicit boundary expectations, leaving little to inference.

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