sw_get_categories

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

Annotations declare readOnlyHint=true, and the description adds the 'hierarchical' nature of the list, which is useful but limited. No additional behavioral context like pagination or structure is given, but the read-only trait is already covered by annotations.

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 short sentences that directly state the purpose and practical usage. No filler or redundancy, every word 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?

The tool is simple with no parameters and a read-only annotation. The description adequately conveys what is returned (hierarchical categories) and how to use the result. It does not specify the exact structure, but that is acceptable for this minimal context.

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 zero parameters, the schema fully covers parameter semantics (100% coverage). The description adds value by explaining the purpose of the returned id, which indirectly supports the output usage rather than parameters. Baseline of 4 is appropriate for 0 parameters.

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 retrieves a 'hierarchical list of Splitwise expense categories,' using a specific verb and resource. It differentiates from sibling tools which focus on groups, users, friends, and expenses.

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 explicit workflow guidance: 'Use the returned id as category_id when creating expenses.' This tells when to use the tool, though it does not mention exclusions or alternatives, which are not necessary here.

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