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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is covered. The description adds the threshold default (0.7) and clarifies that exclude_exact_matches 'drops identical copies' — useful semantics, but no mention of result ranking, scoring semantics, or result volume behavior.

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?

One dense sentence covering purpose and all three optional params, plus a short use-case sentence. Front-loaded and free of filler, though the parameter clauses are packed into a single run-on sentence.

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 an output schema, so return values need not be described, and annotations cover the safety profile. The description supplies purpose, the key parameter behaviors and a use case, leaving only minor gaps (threshold scale, limit default) for a read-only similarity search.

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 0%, so the description must carry the load and largely does: it explains content_sha256 as the file's content hash, threshold as a similarity floor with default 0.7, limit as a cap on results, and exclude_exact_matches as dropping identical copies. It omits the limit default (10) and the direction/scale of the threshold, so it is strong but not exhaustive.

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?

States a specific verb+resource ('Find JavaScript files similar to the file with this content SHA-256'), which distinguishes it from hash-exact siblings like search_js_fingerprint_by_sha256. However, it never names or contrasts with the near-identical siblings get_jsfingerprint_similar or search_js_fingerprint_by_fuzzy_hash, leaving the agent to infer the difference.

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 closing sentence 'Useful for finding modified versions of a known script' gives an implied use case, which is more than nothing. But there is no when-not guidance, no mention of the fuzzy-hash or normalized-hash alternatives, and no prerequisite stating the file must already be indexed.

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