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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so the safety profile is covered. The description adds real context beyond that: verification is against ChainChoice's published keys, and accepted input is either a ChainChoice-served receipt or an issuer envelope. It stops short of disclosing what a failed or malformed verification produces.

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 tight sentences with the verification action front-loaded and the checks enumerated immediately after. The API-endpoint cross-reference is compact and earns its place.

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?

There is no output schema, so the description carries the burden of describing the result, yet it never says what verification returns (a boolean, a status object, per-check breakdown) or how failures surface. The nested receipt object's internal shape is also left entirely unspecified. Adequate for invocation, incomplete for interpreting the outcome.

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 the baseline is 3, but the description genuinely extends the bare schema text 'The receipt JSON, with its signature' by clarifying the two accepted envelope forms. That distinction affects what the agent should pass and is not present in the input schema.

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 ('Checks a signed receipt') and enumerates the exact checks performed: content-hash match and signature validity. No sibling (get_evidence, get_ranking, search, hand_off) performs validation, so an agent can route to this tool unambiguously.

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?

Implies its use case (verifying a receipt you already hold) and adds a useful anchor by noting it is the same verifier as POST /api/v1/verify. However, there is no explicit when-to-use vs. when-not, no guidance on what to do with a failed check, and no prerequisites stated.

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