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

Annotations provide idempotentHint=true and readOnlyHint=false, but the description adds significant behavioral context: the identical response shape for all statuses, the 'unknown' handling without errors, and the monetization via x402 with payment details. These go beyond annotations and help the agent understand side effects (payment) and error behavior.

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 block but efficiently front-loads the core purpose before adding response shape, monetization, and endpoint details. It is longer than minimal but every sentence adds value, with no redundancy. The structure flows logically from what to how to payment.

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 the tool's simplicity and the presence of an output schema, the description covers the key aspects: statuses, response shape, error behavior, payment requirements, and endpoint. It does not explain the parameters, but the output schema and the tool's self-evident purpose reduce the need. It is complete for an agent to invoke correctly.

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 only 33% (only agent_wallet is described). The description does not explain agent_id or idempotency_key, which are required. While agent_id is self-explanatory from the tool name, idempotency_key is a common but not universally understood parameter. The description does not compensate for the low schema coverage, leaving a gap in parameter meaning.

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 verb and resource: 'Check an Agent ID's current standing' with explicit statuses (valid, revoked, expired, unknown). It clearly distinguishes from sibling tools like agentid_issue, renew, and revoke by focusing on verification. The response shape is also described, making the tool's purpose unambiguous.

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 when to use the tool (to check status) and provides context about unknown IDs never erroring. However, it does not explicitly mention alternatives or when not to use it. Since the purpose is obvious and it names no exclusion conditions, it is clear but lacks explicit sibling differentiation.

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