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 meaningful behavior: results include a version breakdown and CDN distribution, and output is paginated via page/per_page. That is genuine value beyond the structured fields.

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?

A single dense sentence, but the core purpose is front-loaded and each clause adds information (examples, version options, output content, pagination). Slightly overloaded with semicolons but no wasted sentences.

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?

An output schema exists, so return values needn't be spelled out, and the description covers pagination and result content. Still, for a 7-parameter tool it omits any meaning for min_confidence and include_cdn_only, leaving notable gaps an agent cannot fill from the schema.

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% across 7 parameters, so the description must compensate. It documents library_name (with examples and alias handling), version, version_pattern, and the page/per_page pagination intent, but says nothing about min_confidence or include_cdn_only, leaving two parameters undocumented everywhere.

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 ('Find') and resource ('scanned JavaScript detected as a given library') and supplies concrete examples ('react', 'jquery', 'nextjs') including an alias mapping. However, it does not distinguish itself from the very similar siblings search_jsfingerprints_by_library and search_js_fingerprint_by_library_version, which an agent must disambiguate.

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 phrase 'optionally one version or a version pattern' implies when to add the version parameters, which is useful implied guidance. But there is no explicit when-to-use/when-not or routing to the near-duplicate sibling tools, leaving the agent to infer selection.

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