Package Vulnerabilities

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 fully covered structurally. The description adds one genuinely useful behavioral fact — the data comes from OSV, which tells the agent about provenance and coverage — but says nothing about breadth (direct vs transitive dependencies), result freshness, or rate limits.

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 short sentences, front-loaded with the core action, with no filler. The trailing ecosystem list is slightly redundant with the schema's ecosystem description, which costs it a point but does let the agent scope the tool without opening the schema.

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?

With an output schema present, return values need no explanation, and annotations carry the safety profile, so the description only needs to establish scope and source — which it does. It is slightly thin on what happens when version is omitted (all versions?) and on dependency scope, but nothing blocks a correct invocation.

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%: name, version, and ecosystem are all documented in the schema, including the exact-name expectation and the version filter semantics. The description's ecosystem enumeration duplicates the schema's own list rather than adding syntax or edge-case detail, so the baseline 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?

States a specific verb and resource ('List known vulnerabilities for a software package') plus the optional version scope and the backing data source (OSV). It is clear on its own, but it never names or contrasts itself with the closest sibling, audit_dependencies, which is also package-oriented.

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?

Usage is only implied: the parenthetical 'optionally a specific version' hints at the version-scoping use case, but there is no when-to-use/when-not guidance and no routing between this, cve_lookup, epss_score, and audit_dependencies. An agent must infer the division of labor from tool names alone.

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