List ICD-11 Chapters

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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint, so the agent knows the operation is safe. The description adds scope details (28 chapters, all areas of medicine, top-level) but does not disclose further behavioral characteristics like ordering, pagination, or output structure. This is acceptable given the annotations, but the added behavioral context is minimal.

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 concise and well-structured. The first sentence clearly states the action, followed by a bulleted list of use cases. The final sentence provides factual context about the 28 chapters. Every sentence serves a purpose, with no fluff or redundancy.

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 listing tool with no required parameters, a full output schema, and comprehensive sibling context, the description covers the essential aspects: what it does, when to use it, and its scope. The use cases are sufficient for an agent to select this tool over siblings. The output schema handles return value expectations.

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 has a single 'language' parameter with 100% description coverage, including default, enum values, and behavior (official translations, no machine translation). The description adds no additional parameter semantics beyond the schema, so the baseline of 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?

The description clearly states 'List all ICD-11 chapters (top-level categories)', specifying the exact verb and resource. It distinguishes this tool from siblings like icd11_lookup (which looks up specific codes) by emphasizing top-level categories and offering use cases like 'overview' and 'navigate to disease categories'.

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?

Provides explicit use cases: get an overview, find which chapter covers a body system, and navigate to specific disease categories. This gives clear context for when to use the tool. It does not name alternative tools, but the implied boundaries (e.g., not for code-level lookup) are evident from the use cases.

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