npmPackageReadme

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

Annotations already provide strong behavioral hints (readOnlyHint: true, openWorldHint: true, idempotentHint: true), so the description doesn't need to repeat safety information. The description adds value by specifying what content is retrieved ('README content'), but doesn't provide additional context about rate limits, authentication needs, or what happens with invalid package names beyond what annotations imply.

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 a single, efficient sentence that immediately communicates the core functionality without any wasted words. It's perfectly front-loaded with the essential information, making it easy for an agent to parse and understand quickly.

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 tool's moderate complexity (single parameter, read-only operation) and rich annotations covering safety and behavior, the description is adequate but minimal. Without an output schema, it doesn't describe what format the README content returns in (e.g., markdown, HTML, plain text), which could be important context for an agent processing the 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?

With 100% schema description coverage, the parameter 'packages' is already well-documented in the schema as 'List of package names to get READMEs for'. The description doesn't add any meaningful parameter semantics beyond what the schema provides, such as format examples, package name validation rules, or handling of multiple packages, so it meets the baseline for high schema coverage.

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 the verb ('Get') and resource ('README content for NPM packages'), making the purpose immediately understandable. However, it doesn't explicitly distinguish this tool from similar siblings like 'npmRepoStats' or 'npmSearch' that might also provide README-related information, which prevents a perfect score.

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 provides no guidance on when to use this tool versus alternatives. With multiple sibling tools like 'npmSearch' (which might return package metadata including READMEs) or 'npmRepoStats' (which could include repository documentation), there's no indication of when this specific README-focused tool is preferred, leaving usage context unclear.

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