mcp-shield

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

With no annotations provided, the description carries full burden and does well by disclosing key behaviors: it downloads packages, performs multiple security checks, and returns a structured report with severity ratings. It doesn't mention performance characteristics, rate limits, or authentication needs, but covers the core operational behavior adequately for a scanning tool.

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, dense sentence that efficiently conveys purpose, scope, and output without wasted words. It's front-loaded with the core action and resource, making it immediately understandable while remaining appropriately sized for the tool's complexity.

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, no annotations, and no output schema, the description does well by explaining what the tool does and what it returns. However, it could better address behavioral aspects like error handling or performance expectations to be fully complete for a security scanning operation.

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%, so the schema already documents both parameters thoroughly. The description adds no additional parameter semantics beyond what's in the schema, maintaining the baseline score of 3 for adequate but not enhanced parameter documentation.

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 specific action ('Download an npm MCP server package and scan it') and resource ('npm MCP server package'), with detailed scope ('for backdoors, exfiltration code, obfuscation, dangerous code execution, and supply chain risks'). It distinguishes from sibling tools like 'audit_supply_chain' by focusing on package scanning rather than broader supply chain auditing.

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 usage for npm package security scanning, but provides no explicit guidance on when to use this tool versus alternatives like 'audit_supply_chain' or 'scan_directory'. It doesn't mention prerequisites, exclusions, or comparative scenarios, leaving usage context to inference.

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