List Dir

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

With no annotations provided, the description carries the behavioral disclosure burden. It does state that the tool lists entries with name, is_dir, size, and mtime, which is useful. However, it does not mention behavior for nonexistent paths, permissions, hidden files, or whether symbolic links are followed.

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, front-loaded sentence with no filler. Every word adds meaning: the operation, the target, and the output fields are all conveyed efficiently.

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 tool has a simple interface (one optional parameter) and an output schema, so the description does not need to restate return types. The main missing piece is error behavior for invalid paths, which is a minor concern for a read-only listing tool.

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 0%, so the description must compensate. It clarifies that 'path' refers to a directory, but it does not add details about accepted path formats, the default '.', or edge cases. The single self-descriptive 'path' parameter keeps this from being a critical gap.

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 names a specific verb ('List') and a specific resource ('contents of a directory'), and specifies the returned fields (name, is_dir, size, mtime). This clearly differentiates it from siblings like read_file, stat, and glob_search, which serve different listing/metadata purposes.

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 it should be used when a directory's entries are needed, but it does not explicitly state when to prefer this tool over alternatives like glob_search or stat. There are no exclusions or alternative-routing hints provided.

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