ap_fs_mkdir

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

With no annotations provided, the description carries the full burden. It adds the useful behavioral nuance that the operation runs 'as the ArmorPaint process', implying its filesystem context. However, it does not mention error behavior, whether existing directories are tolerated, or whether parent directories are created.

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?

A single sentence with no wasted words. The core action is front-loaded, and the example usage directly follows. Every element earns its place.

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 one-parameter filesystem creation tool with no output schema, the description is sufficiently complete for an agent to invoke it correctly. The path format is fully documented in the schema, and the purpose is clear. Minor gaps like return value or existence handling do not materially hinder 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?

Schema description coverage is 100%, and the path parameter is already well documented in the schema: absolute path, forward slashes, and automatic backslash conversion. The description adds no parameter semantics beyond the schema, so baseline 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?

Description states a precise verb and resource: 'Create a directory (as the ArmorPaint process)'. It clearly distinguishes this tool from filesystem read siblings like ap_fs_list and ap_fs_stat, and the example 'before an export' reinforces its purpose.

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: create a directory as the ArmorPaint process, e.g., before an export. It does not explicitly name alternatives or exclusions, but none are needed since the tool name and sibling set make the read-vs-write distinction obvious.

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