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

Annotations already declare readOnlyHint and openWorldHint, so safety is partly covered; the description adds meaningful context beyond them: the data source (OSV.dev), coverage (vulnerabilities and malware), returned fields, and the pricing/auth model (USDC, x402 or prepaid credits, free trial). The idempotentHint=false tension with readOnly is not addressed, but the pricing and source disclosure are genuine added value.

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?

Front-loads the core action and scope, then return fields, then pricing. Every sentence carries information, though the pricing sentence adds a small amount of noise for an agent focused purely on invocation semantics.

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 and 100% schema coverage, the description need not explain return values or parameter formats; it nonetheless covers scope, source, ecosystems, and cost. An agent has everything needed to decide and call correctly.

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%, so the enum, the 200-item cap, and the exact-version format are already documented in the schema. The description reinforces 'up to 200 exact ... versions' but adds no syntax or semantics beyond what the schema provides; 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 (audit) and resource (whole dependency list), plus concrete scope: up to 200 exact versions across npm, PyPI, crates or Go, checked against OSV.dev. The 'whole dependency list in one call' phrasing distinguishes it from single-package siblings like package-check and dependency-report.

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 batch framing implies when to use it (auditing many packages at once) but there is no explicit when-not guidance and no named alternatives, despite several plausible siblings (package-audit-lockfile, package-check, dependency-verdict) that an agent must differentiate on its own.

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