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

Annotations already indicate readOnlyHint, openWorldHint, idempotentHint, destructiveHint. The description adds significant behavioral context: partial failures degrade gracefully, bundlephobia's first measurement may take 5-30s, and sources_failed will list timeout. This goes well beyond annotations.

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?

The description is comprehensive and well-structured, starting with purpose, then usage, ecosystem limitation, and graceful degradation. Slightly verbose but every sentence adds value. Could be tightened while retaining clarity.

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?

Given the lack of output schema, the description details the return information: summary fields, per-advisory detail, links, alternative versions. It also covers error behavior (timeout, sources_failed). This makes the tool fully self-contained and usable without external documentation.

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 100% with descriptions for both parameters. The description adds further context: 'package' accepts scoped packages like @types/node, 'version' defaults to latest when omitted. It also previews return fields, which is helpful since there is no output schema.

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 it is a 'composite should I add this npm package to my project check in ONE call' and specifies the sources (deps.dev, bundlephobia) and what it checks (license, advisories, version history, bundle size). This sets a clear and specific purpose that distinguishes it from sibling tools, which cover different domains.

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?

Explicitly says 'Use whenever an agent asks "is X safe / popular / small" or "what does adding lodash cost me"'. Also notes ecosystem limitation: 'NPM ecosystem only in v1; PyPI / Maven / Cargo / Go fall under deps.dev:version directly', providing clear when-to-use and when-not-to guidance without naming alternative tools.

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