scan_summary

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

The description explicitly notes 'read-only', a key behavioral trait absent from annotations. However, it does not disclose other behaviors such as handling of symlinks, the maxFiles limit, or potential performance implications. With no annotations, the description carries the burden but only partially fulfills it.

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, well-front-loaded sentence. It states the core purpose and two key features without redundancy. Every word contributes value.

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?

With 6 parameters and no output schema, the description covers the core behavior but omits important constraints like maxFiles limit, symlink handling, and the nature of the report. It does not explain how the summary is returned or any resource limitations, leaving the agent with partial contextual understanding.

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 83%, so the baseline is 3. The description mentions 'ignore globs and depth limits', aligning with ignoreGlobs and maxDepth, but adds nothing beyond the schema's existing parameter descriptions. The rootPath parameter lacks a schema description, but the description implies it via 'Scan a directory'.

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 (scan), resource (directory), and outcome (summarize total size, files, dirs). It distinguishes this tool from siblings like top_dirs or top_files by emphasizing a general summary rather than specific rankings.

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 obtaining directory statistics but does not explicitly state when to prefer this tool over alternatives or when not to use it. No exclusions or alternative tool references are provided, leaving the agent to infer context.

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