list_categories

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

No annotations are provided, so the description carries the full burden for behavioral disclosure. The description implies a read-only operation by saying 'List' and 'Returns categories with their tool counts,' but it does not explicitly state that it causes no side effects or requires no special permissions. Since this is a simple listing tool, the lack of explicit safety language is acceptable but leaves room for ambiguity.

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 exactly two sentences, front-loaded with the primary action ('List all tool categories in the graph'), and adds only relevant additional detail about return values and use case. Every word earns its place—no redundancy or fluff.

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?

The tool is simple with no parameters and an output schema also exists, so the description does not need to detail return structures. The description explains what is returned (categories with tool counts), why it is useful (understanding the tool landscape), and when to use it (before searching). This is complete for the tool's complexity.

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 and the input schema is an empty object with 100% schema description coverage. Since there are no parameters to explain, the description does not need to add parameter semantics. The baseline for no parameters is 4, which 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?

The description clearly states the tool's function: 'List all tool categories in the graph.' The verb 'List' is specific, the resource is 'tool categories in the graph,' and the scope is explicit. It also distinguishes itself from siblings like search_tools by positioning categories as an overview tool before searching.

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 the tool: 'useful for understanding the available tool landscape before searching.' This implies using it as a precursor to search_tools, but it does not explicitly mention when not to use it or name alternative tools directly. Still, the usage context is evident.

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