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

With no annotations, the description carries the burden and largely meets it: it discloses pricing ($0.01 USDC per call via x402), that bad input and upstream errors are not charged, and data provenance/licensing (OSV.dev CC-BY 4.0, deps.dev). It omits auth/wallet setup details implied by x402 and any rate-limit 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?

Front-loaded with the core action and scope, then layers input formats and return shape efficiently with zero filler. The middle sentences are densely packed into run-ons, which slightly hurts scanability but every clause carries information.

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?

No output schema exists, and the description fully compensates by enumerating the return payload (per-package vulnerable flag, vuln count, max severity, max CVSS v3, recommended upgrade, advisory fields, severity totals, unique vulns, skipped entries). An agent has enough to decide, invoke, and interpret results.

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 coverage is already 100%, so the schema documents each parameter, but the description adds real meaning: the three alternative input shapes, worked example strings for the comma format, and the semantic rule that range minimums are used for package.json versions.

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 ('Audit up to 50 dependencies in one call') plus the backing service (OSV.dev querybatch). The batch scope of up to 50 packages implicitly distinguishes it from the single-package siblings package_advisories and vuln_details.

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?

Gives concrete entry paths (items array, packages string, manifest text, or raw POST body) and names the manifest formats accepted, so an agent knows how to invoke it. It stops short of saying when to prefer this over package_advisories or vuln_details for a single package or a deep advisory dive.

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