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

Beyond the readOnlyHint and openWorldHint annotations, the description reveals important behavior: it returns the caller's own plus public scans, sends no data externally, and deliberately returns an empty list for unknown or unauthorized hashes without distinguishing the two. This visibility protection is significant and well documented.

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?

Three concise sentences, each earning its place: the first states the core purpose, the second defines result scope, and the third explains edge-case behavior. All key information is front-loaded without redundancy.

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 description is complete for a single-parameter lookup tool: it covers the operation, result content, privacy behavior, and empty-result semantics. The output schema handles return structure, and no critical calling context is missing.

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% and the parameter description already clearly defines a 64-character hex SHA-256 digest. The tool description adds no new parameter-level detail beyond what the schema provides, so the baseline score 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 states a specific verb ('Find'), a specific resource (analyses of a SHA-256 digest), and clarifies scope: the caller's own scans plus public scans. This clearly separates it from siblings like submit_scan (which creates scans) and makes its lookup role 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?

The description makes the use case clear: use this when you already have a known SHA-256 digest and want to retrieve existing analyses. 'Sends nothing anywhere' and 'searches scans that already exist' imply a safe, read-only lookup, though it does not explicitly name alternatives or state when not to use it.

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