listdir

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

With no annotations, the description discloses skipping hidden and build/vendor directories, default flat listing, max_depth default, and relative_paths token savings. It does not cover error handling or permissions, but the key behaviors are transparent.

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?

Six sentences total. The first sentence states purpose, followed by concise parameter guidance. No redundant or filler content. Front-loaded with most important info.

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 no output schema, the description explains output formats (flat vs tree). It covers all parameters, default values, and behavioral notes (skipping dirs). Missing error handling or permissions, but sufficient for typical usage.

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 coverage is 100%, so baseline is 3. The description adds value by explaining defaults (flat, max_depth, relative_paths) and the token-efficiency rationale, improving semantic understanding beyond parameter names.

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 begins with 'Lists directory contents,' a clear verb+resource pair. It distinguishes from sibling tools like glob, grep, and file_info by focusing on listing directory contents with optional tree structure.

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 explains default behavior (flat listing) and when to use alternatives (flat=false for tree, relative_paths to save tokens). It provides context on token efficiency and traversal depth but lacks explicit when-not-to-use or alternative tool references.

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