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

Annotations already declare readOnly, idempotent, non-destructive and closed-world behavior, so the safety profile is covered. The description adds genuinely useful context beyond that: the language-normalization layer with a concrete example ('aussteller' → exhibitor), the corpus boundaries, and the fact that results are ranked and carry reusable ids.

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?

Three sentences, front-loaded with what is searched before the language behavior and the return-value note. The long parenthetical enumerating the guides is dense but each clause carries real information; no sentence is filler.

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?

With no output schema, the description carries the return-value burden and discharges it ('ranked hits with ids usable in get_endpoint / get_guide'). Combined with the searchable-corpus definition and the bilingual query behavior, an agent has everything needed to call this correctly.

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 description coverage is 100% — both query and limit are documented with examples and constraints in the schema itself. The description's language note reinforces the schema's bilingual examples but adds no syntax, format, or defaulting detail beyond it, so baseline 3 applies.

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?

States a precise verb (full-text search) and enumerates the searchable corpus: API modules, endpoint name/path/description, and named guides. This clearly distinguishes it from the retrieval-by-id siblings get_endpoint and get_guide, and from the listing tools.

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 closing sentence routes the agent forward — 'Returns ranked hits with ids usable in get_endpoint / get_guide' — which establishes the intended search-then-fetch workflow. It also tells the agent non-English (German) queries are valid, but never states when to prefer search over list_endpoints/list_modules.

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