scan_directory

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

No annotations are provided, so the description carries the full burden. It states that the tool reads files from the filesystem (access behavior), returns security scores and findings, and mentions truncation. However, it does not disclose whether the tool is entirely non-destructive, any authentication or permissions required, or other side effects like network access or rate limits.

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 including an example. It is front-loaded with the main purpose, and every sentence serves a purpose: stating action, explaining input and behavior, noting truncation, and giving an example. No waste.

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 tool with 5 parameters and no output schema, the description covers the key output features (security score A-F, findings, fileRanking) but does not enumerate all possible result fields. It provides enough context for basic usage but could be more complete regarding error handling or structure of findings.

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 baseline is 3. The description adds value with an example usage and a note about fileRanking for truncated results, but does not provide additional semantics beyond what the schema already offers for parameters like recursive, exclude, format, and baseline.

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 'Scan all files in a directory on disk for security vulnerabilities', which is a specific verb+resource action. This distinguishes it from sibling tools like 'scan_file' (single file) and 'scan_dependencies' (dependencies).

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 usage context: 'Pass a directory path — reads files from filesystem' and notes that results may be truncated for large projects, suggesting when to check fileRanking. However, it does not explicitly guide when to use this tool vs alternatives like scanning individual files or dependency scans.

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