list_categories

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

No annotations are provided, so the description must convey behavioral traits on its own. The verb 'List' implies a read-only operation, and the description adds purpose, but it does not explicitly state whether the operation is safe, what side effects (if any) exist, or whether permissions are required. For a simple read operation, this is adequate but not rich.

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 plus a brief parameter note, with no wasted words. The main purpose is front-loaded, and the structure (description followed by Args) is clean and easy to scan.

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 list tool with a single parameter and an output schema, the description provides all necessary context: what it lists, why to use it, and how to use the parameter. The output schema covers return values, so no further explanation is needed.

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 input schema provides only type and requirement, with no description for course_id. The description compensates fully by explaining the parameter's meaning and how to find it, explicitly referencing list_courses. This is clear and actionable.

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 function: listing thread categories and subcategories for a course. The verb 'List' plus the specific resource 'thread categories and subcategories' is specific and distinguishes it from siblings that manage threads themselves.

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 explicitly says to use this tool to find valid category names before creating or recategorising threads, which provides clear usage context. It does not mention exclusions or alternative tools for the same purpose, but it does reference list_courses for finding the course ID, offering relevant contextual guidance.

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