List Allowed Directories

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

The description discloses that the tool returns allowed directories and that subdirectories are also accessible, adding useful behavioral context. Since readOnlyHint=true is already annotated, the description does not need to restate read-only behavior but still provides additional scope information.

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 two sentences, front-loaded with the primary purpose, and then provides usage context. No redundant information.

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 simplicity of the tool (no parameters) and the presence of an output schema, the description fully covers the purpose and usage. No missing information for correct invocation.

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 tool has zero parameters, so the schema coverage is 100% by definition. Baseline for 0 params is 4; the description appropriately does not need to add parameter-specific details.

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 returns the list of allowed directories, distinguishing it from sibling tools like list_directory or read_file. It is specific about the resource (allowed directories) and the action (listing).

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?

Explicitly tells the agent when to use it: before trying to access files, to understand which directories and nested paths are available. This provides clear guidance and implicitly contrasts with guessing directory paths.

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