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

The annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile and the fact that data comes from an external catalogue are covered. The description confirms that this is a read-only reference lookup, but adds nothing about result volume, caching, or fallback behavior when no theme matches.

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?

Two short sentences, zero filler, with the output shape stated first and the downstream use second. Nothing can be removed without losing meaning.

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?

An output schema exists, so return values need no explanation, and the tool is a simple reference lookup with only three parameters. The only real gap is the lack of guidance on match behavior for `query` and on whether an empty result is possible.

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?

Schema coverage is 67%; market and language are documented in the schema, including the 'ask when unknown' note for market. The description only clarifies that `query` is an optional free-text filter, and does not explain matching semantics (prefix vs substring) or how language affects theme names, so it adds little beyond the schema.

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 states a specific verb and resource ('Find catalogue theme IDs and names') and names the payload (IDs and names), so the agent knows what comes back. It does not explicitly name a sibling like search_sets, but the phrase 'narrow a set search' still signals the relationship to it.

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?

'optionally by text' and 'can be used to narrow a set search' imply when this tool is useful: resolving a theme before filtering returns from search_sets. However, it never states when not to use it, or whether a bare list is returned with no query, so the routing guidance is implied rather than explicit.

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