scan_purl

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

Annotations already declare readOnlyHint=true, so the description does not need to state it is read-only. However, the description adds no behavioral details beyond the purpose, such as rate limits, scope of vulnerabilities (e.g., public vs private), or how results are aggregated.

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?

Two sentences with no superfluous information. The key purpose and a usage example are front-loaded. Every sentence serves a purpose.

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?

For a simple lookup tool with 2 parameters and no output schema, the description adequately conveys the core functionality. However, it does not specify the return format (e.g., list of CVEs with details) or whether the severity parameter is supported. A more complete description would mention output structure or limitations.

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 descriptions for both parameters (purl and severity) with 100% coverage. The description adds a concrete example for purl, but does not elaborate on severity or any default behavior. 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 clearly states the action ('Look up known vulnerabilities'), the resource ('a specific package using its Package URL'), and the context ('checking if a specific dependency version is affected by any CVEs'). This distinguishes it from sibling scanning tools that focus on filesystems or images.

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 provides context ('checking if a specific dependency version is affected by any CVEs') but does not explicitly state when to use this tool versus alternatives like scan_sbom or vulnerability_report. No exclusion criteria or alternatives are mentioned.

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