NPM Sentinel MCP

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

Annotations already provide readOnlyHint=true, openWorldHint=true, and idempotentHint=true, indicating it's a safe, idempotent read operation that can handle unknown packages. The description adds value by specifying the metrics (quality, maintenance, popularity) used for scoring, which isn't covered by annotations, but doesn't detail rate limits, auth needs, or output format.

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 directly states the tool's purpose without unnecessary words. It's front-loaded and every part contributes to understanding, making it highly concise and well-structured.

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 (retrieving consolidated scores), annotations cover safety and idempotency, and the input schema is fully described, the description adequately explains what it does. However, without an output schema, it doesn't detail the return format or scoring scale, leaving some gaps in completeness.

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 input schema fully documents the single parameter 'packages'. The description doesn't add any parameter-specific details beyond what's in the schema, such as format examples or constraints, 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 action ('Get consolidated package score') and the resource ('package'), specifying it's based on quality, maintenance, and popularity metrics. However, it doesn't explicitly differentiate from sibling tools like 'npmQuality', 'npmMaintenance', or 'npmTrends' which might cover similar aspects individually, making it clear but not fully sibling-distinctive.

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 like 'npmQuality' or 'npmMaintenance', nor does it mention any prerequisites or exclusions. It's a basic statement of function without contextual usage advice.

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