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

The description discloses behavioral traits: it only checks the signature, requires exact metadata, and warns against sending file bytes. Without annotations, this adequately covers the tool's safety and idempotency, though it could mention if the tool has side effects or rate limits.

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 concise and front-loaded with the main purpose. It uses two paragraphs efficiently, but the second paragraph could be slightly tighter. Overall, it earns its length without being verbose.

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?

Despite clear purpose and parameter details, the description lacks information about return values or output behavior. Since there is no output schema, the agent would benefit from knowing what the tool returns (e.g., boolean success). This gap mildly reduces completeness.

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% with detailed parameter descriptions. The description adds contextual value by explaining the requirement for exact metadata matching and the format of the attestation string, complementing the schema. The added meaning lifts it above the baseline of 3.

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 clearly states the tool verifies the HMAC signature of an attestation, specifying what it confirms (authenticity and integrity of the attestation string and metadata) and what it does not (file matching). It distinguishes itself from other tools by focusing solely on signature verification.

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?

Guidance is provided on when to use this tool (for HMAC verification) and when additional steps are needed (local file hash checking). It also emphasizes exact metadata matching. However, it does not explicitly compare to sibling tools like 'attest_hash' or 'create_certificate_pdf', which could clarify alternatives.

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