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

Annotations already mark it read-only, idempotent, and non-destructive, and the description adds useful behavioral context: verification is offline and tampered claims fail. It does not contradict the annotations and provides a meaningful safety and behavior hint.

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 two short sentences plus a sibling pointer, front-loading the core purpose. 'Tampered claims fail' and the sibling note are both informative without padding. The only minor ambiguity is the cryptic '2c', but it does not undermine overall clarity.

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 simple read-only verification tool with a complete input schema and an output schema present, the description covers the key behavior and relationship to vc_attest. It does not elaborate on the output format, but that is handled by the output schema, and '2c' is not explained, leaving a small gap.

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%, so the baseline applies and the description need not repeat parameter details. The description's 'signed attestation' and 'Tampered claims fail' loosely contextualize the claim, but it adds no parameter-specific syntax beyond the 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?

The description states a specific action and object: 'Verify a signed attestation offline', which clearly distinguishes it from the sibling vc_attest. The statement 'Tampered claims fail' makes the verification outcome explicit. This is more than a tautology and gives an agent enough to know what the tool is for.

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 sibling reference 'Sibling: vc_attest' plus the schema note that the claim is 'returned by vc_attest' imply a verification-after-creation workflow. This is clear context, though it stops short of explicitly stating when not to use the tool or listing alternatives beyond the one sibling.

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