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

No annotations are provided, so the description carries the full burden of disclosing behavior. It states that the tool 'Verify a non-membership proof,' implying a read-only check, but it does not disclose the return value, error handling, side effects, or permissions required. The phrases 'Reference-grade implementation' and 'wire format normative' provide some context about quality and standards, but they do not describe the tool's runtime behavior or outcomes.

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, leading with the core purpose in the first sentence, followed by two short contextual statements about implementation grade and wire format. Each sentence contributes useful information without excessive length. The structure is front-loaded and easy to scan.

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?

The tool has no output schema and no annotations, yet the description does not explain what the tool returns (e.g., boolean, void), how it signals invalid proofs, or any side effects. It also omits details about edge cases, such as handling of malformed proof objects or invalid root hex strings. Given the tool's complexity (nested proof object, specific domain), the description is incomplete for an agent to confidently invoke it without further assumptions.

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?

The input schema already provides clear descriptions for both parameters: 'proof' is 'Non-membership proof from attest_absence_prove' and 'root_hex' is 'Expected Merkle root (hex)'. The description adds no additional semantic detail beyond what the schema offers. With schema description coverage at 100%, the baseline of 3 is appropriate.

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's verb and object: 'Verify a non-membership proof against an expected Merkle root (C13).' This distinguishes it from sibling verification tools (e.g., attest_custody_verify, attest_passport_verify) because it explicitly targets non-membership proofs for absence attestations. The mention of 'C13' adds concreteness, making the 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?

Usage context is implied rather than explicit. The description indicates this tool verifies non-membership proofs, and the input schema references attest_absence_prove as the source of the proof, suggesting it is the counterpart to that tool. However, it does not explicitly state when to use this over other verification tools or when not to use it. The note 'production-grade is Layer B' implies a higher-grade alternative exists but does not directly say 'use that instead for production.'

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