List Directory

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

The readOnlyHint annotation indicates no modifications, and the description does not contradict this. It adds the constraint of working only within allowed directories, which is useful context beyond the annotation.

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 concise and well-structured, with the purpose stated first and the prefix detail second. The third sentence contains some redundant fluff about being essential, but overall it is efficient.

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?

The description mentions the [FILE] and [DIR] prefixes but does not specify whether the listing is recursive or how the paths are formatted. It also lacks information about error handling or the exact output structure, leaving some gaps.

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?

The only parameter 'path' is described merely as 'a specified path' in the description, with no details on format (relative/absolute) or constraints. Since the schema has no description, the tool description fails to adequately define the parameter semantics.

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 that the tool lists files and directories in a given path and highlights the [FILE] and [DIR] prefixes. It distinguishes from sibling tools by focusing on a simple listing, though it doesn't explicitly contrast with directory_tree or list_directory_with_sizes.

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 exploring directory structure and finding files, but it does not explicitly specify when to prefer this over search_files or directory_tree. It provides a constraint that it only works within allowed directories, but lacks direct comparisons to alternatives.

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