npm_downloads_bulk

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false. The description adds operational constraints: 128 package limit, scoped packages unsupported, and the bulk endpoint nature. These are valuable behavioral details beyond annotations, though return format and pagination are not covered.

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?

Two sentences, front-loaded with purpose, then critical constraints. No filler or repetition of schema details.

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?

For a read-only bulk query tool with full schema coverage and safety annotations, the description covers the key use case, constraints (128 max, no scoped packages), and points to an alternative for unsupported packages. It does not describe the exact output shape, but no output schema exists and the task is simple enough that this is minor.

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%: packages and period are already described ('Array of package names to compare (unscoped only)' and 'Period (default: last-week)'). The description adds no new parameter-level meaning beyond reinforcing the unscoped constraint and the bulk limit, which already appears in schema maxItems. Baseline 3 applies when schema covers parameters.

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?

Description opens with a specific verb 'Compare' and resource 'download counts for multiple packages over a period', clearly distinguishing it from single-package siblings like npm_downloads. The explicit 128-package limit and scoped-package exclusion further clarify scope.

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 states that scoped packages are not supported and instructs to call npm_downloads separately per scoped package, providing a clear when-not and alternative. However, it does not explicitly contrast with using npm_downloads for single unscoped packages, though the bulk purpose is evident.

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