topics_index

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It does not mention any side effects, readonly behavior, or caching. For a zero-parameter tool, it is adequate but lacks detail on output structure or update frequency, though an output schema exists.

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: three sentences covering purpose, scope, and usage guidance. No redundant phrases, and the structure is front-loaded with the core function.

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?

Given the tool has no parameters and an output schema exists, the description provides sufficient context: it explains what the tool returns (topic-code mapping), lists covered areas, and suggests downstream tools. No additional information is necessary for 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?

There are no parameters, so schema coverage is trivially 100%. The description adds no parameter information because none exist. With zero parameters, a baseline of 4 is appropriate; the description does not need to add parameter semantics.

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 it is a curated index that maps topics to indicator codes, listing a broad range of health system topics. This distinguishes it from siblings like get_indicator_metadata or compare_countries, which operate on individual codes rather than providing a topic-to-code mapping.

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 tells the user to pass returned codes to get_indicator_metadata or compare_countries, providing clear next steps. While it doesn't explicitly state when not to use this tool, the context implies it is the starting point for topic exploration, and no alternatives are mentioned, which is acceptable given its unique role.

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