list_directory

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

With no annotations, the description carries the full burden of behavioral disclosure. It only reveals that the tool shows files and subdirectories, but omits behaviors such as whether hidden files are shown by default (controllable via the showHidden parameter), what the 'simple' vs 'detailed' formats entail, and how errors like nonexistent paths are handled. The description adds minimal context beyond the tool's name.

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 conveys the core function without any redundant information. Every word contributes to the meaning, making it an exemplary model of efficiency. This earns a 5.

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 the lack of annotations and output schema, the description should compensate by explaining return format, defaults, or edge-case behavior. It does none of this. The tool has three parameters and could reasonably be expected to describe its output structure or sorting behavior. The description is minimal and leaves important usage context unaddressed, so a score of 2 reflects its incomplete nature.

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 100%, with each parameter having a clear description. Per the rubric, baseline is 3 when the schema covers parameters fully. The tool description itself adds no parameter semantics beyond what the schema already provides, so a score of 3 is appropriate.

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 tool's purpose: 'Lists the contents of a directory, showing both files and subdirectories.' It uses a specific verb (lists) and resource (directory contents), and the inclusion of both files and subdirectories distinguishes it from file-specific tools like read_file and get_file_info. This meets the 5-point criterion of specific verb+resource with clear differentiation.

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 provides no guidance on when to use this tool versus alternatives. Sibling tools like list_project_files and find_files likely overlap in functionality, but the description does not mention any distinguishing use cases or exclusions. An agent receives no direction on tool selection, resulting in a score of 2 (no guidance).

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