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

With no annotations provided, the description bears full responsibility for behavioral disclosure. It mentions the implementation is reference-grade and wire format normative, but does not explain side effects (e.g., state changes), input requirements, return values, or error behavior. The cryptic 'Layer B' reference adds confusion rather than clarity.

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 at three sentences, with the main purpose front-loaded. It avoids unnecessary words, but the inclusion of cryptic terms like 'C13: prov-absence' and 'Layer B' could be more clearly explained, slightly reducing 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?

Given the tool's complexity (building a cryptographic tree), the description is sparse. It does not explain the structure of the 'events' input, expected output, or preconditions (e.g., sorting requirements). Without an output schema, the agent is left without enough information to correctly invoke the tool.

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% (window_id and events are described in the schema), so the baseline is 3. The description adds no additional parameter meaning beyond what the schema already provides, so it neither enhances nor harms parameter understanding.

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 function: 'Build a sorted Merkle tree for an audit window'. This is a specific verb+resource combination that distinguishes it from sibling tools like attest_absence_prove and attest_absence_verify, which deal with proof generation and verification rather than tree construction.

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 implies usage context — building a tree enables non-membership proofs — but does not explicitly state when to use this tool versus alternatives. The note about 'Reference-grade implementation' and 'production-grade Layer B' hints at intended use cases but lacks clear exclusions or alternative recommendations.

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