npm Package Info

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

Annotations already declare readOnly, destructive, idempotent, and openWorld hints. The description adds value by listing the specific data fields returned and clarifying version behavior, which goes beyond what annotations provide. No contradictions.

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 three sentences long, front-loading the core purpose, then adding scale and parameter behavior. No extraneous information; every sentence is necessary.

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 simple tool (2 parameters, output schema present, rich annotations), the description covers the key aspects: what is returned, scoped package support, and version behavior. It could mention that it fetches from the npm registry, but that is implied.

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 clear parameter descriptions. The description reinforces the version default and supports scoped packages, but does not significantly augment the schema’s already informative descriptions.

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 uses the specific verb 'Get' and identifies the resource as 'metadata for any npm package', listing concrete fields. It also mentions scoped packages and version defaults, clearly distinguishing it from sibling tools like 'npm.packages.search' or 'npm.packages.versions'.

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 implies the tool is for fetching metadata of a known package, but does not explicitly state when to use it over alternatives (e.g., 'use search to find packages' or 'use versions to list all versions'). No direct exclusion or when-not-to-use guidance is provided.

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