create_directory

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

Without annotations, the description carries the full burden. It discloses the parent-directory creation behavior, but omits the default project-root restriction and the need for explicit approval for external access, which is only in the schema. It also doesn't state what happens when the directory already exists.

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 that is entirely relevant, with no wasted words. The parenthetical clarification is valuable.

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 creation tool, the description covers the core purpose and the recursive behavior, but it lacks mention of the default project-root boundary and the return value. The schema fills parameter details, but the description alone is minimal for full contextual understanding.

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 both dirPath and allow_external_access having descriptive text. The description itself adds no parameter information beyond the schema, so baseline 3 applies.

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?

Description clearly states 'Create a new directory (Including parent directories).' with a specific verb and resource, and the parent-directory behavior distinguishes it from generic 'create' tools. No sibling tools overlap with this exact operation.

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 its use for creating directories but does not explicitly specify when to use it over alternatives like run_shell with mkdir, nor does it provide exclusion criteria. The parent-directory note gives some context, but no explicit guidance.

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