Create Directory

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

The description adds valuable behavioral context beyond annotations: it explains idempotent behavior ('if directory already exists, succeeds silently'), mentions creating nested directories, and specifies the constraint about allowed directories. While annotations cover readOnlyHint, idempotentHint, and destructiveHint, the description provides practical implementation details that enhance understanding.

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 efficiently structured with four concise sentences, each adding distinct value: core functionality, idempotent behavior, use cases, and constraints. There's no redundancy or wasted words, and key information is front-loaded.

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 tool's moderate complexity, comprehensive annotations, and existence of an output schema, the description provides complete contextual understanding. It covers purpose, behavior, constraints, and use cases without needing to explain return values (handled by output schema) or repeat annotation information.

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?

With 0% schema description coverage for the single 'path' parameter, the description compensates by explaining what the path represents ('directory or nested directories') and the operational context ('within allowed directories'). It doesn't provide format examples or syntax details, but adds meaningful semantic context beyond the bare schema.

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 with specific verbs ('create', 'ensure exists') and resource ('directory'), distinguishing it from siblings like list_directory or move_file. It explicitly mentions creating nested directories, which differentiates it from simpler file operations.

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 clear context for when to use this tool ('setting up directory structures', 'ensuring required paths exist') and mentions constraints ('only works within allowed directories'). However, it doesn't explicitly state when NOT to use it or name specific alternatives among the sibling tools.

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