list_directory

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

With no annotations, the description carries the full burden. It discloses the output metadata (size, isDirectory, modified date) but does not state edge-case behavior such as error handling for nonexistent paths, whether hidden files are included, or whether it follows symlinks. The verb 'list' implies a non-destructive read, but this is not explicitly confirmed.

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 concise sentence that front-loads the action and resource, then immediately provides the useful metadata detail. No wasted words.

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 simple single-parameter directory listing tool, the description adequately covers purpose and expected output. It lacks edge-case behavior, but the tool's simplicity and the metadata mention make it sufficiently complete for most use cases. No output schema exists, so the description partially fills that gap.

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% and the description does not add meaningful parameter semantics beyond the schema. The schema already states 'Path to the directory to list', and the description only repeats the directory concept. No additional constraints, formats, or usage details are provided.

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 'List all items inside a directory with metadata (size, isDirectory, modified date).' This is a specific verb+resource combination that distinguishes it from siblings like read_file (reads file content) and get_file_info (single item info). The scope is unambiguous.

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 when to use: whenever you need to enumerate directory contents. It does not explicitly mention alternatives or exclusions, but the purpose is clear enough that an agent can infer appropriate usage. Sibling tools like search_files and get_file_info serve different purposes, making the intended use obvious.

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