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

Annotations only declare readOnlyHint=true, so the description carries real added weight: it discloses that summary contains title plus the first 500 chars of body (truncation), that structuredContent holds only id+title and not the full body, and that an unknown id yields wissen_not_found. These are concrete behavioral traits beyond the annotation.

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?

Labeled fragments (WHAT / REQUIRED / NEXT) front-load the purpose, required input, output caveat, error case, and follow-up in a handful of words. Every sentence earns its place with no 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?

An output schema exists, so return values need not be spelled out, and the description still adds the crucial summary-truncation and structuredContent limitations plus the not-found behavior and a next step. Nothing needed to invoke it correctly is missing.

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%, with the id param and the locale enum both fully documented in the schema. The description repeats only that id is REQUIRED and adds no syntax, sourcing, or locale behavior beyond the schema, so the 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?

The description opens with 'WHAT: One Wissen article', which names the exact resource and its singular scope, implicitly contrasting with the sibling list_wissen. It is clear what the tool fetches, though the verb is implied by the tool name rather than stated.

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 'NEXT:' clause routes the agent to get_ai_page or the canonicalUrl fragment after a lookup, which is useful follow-up guidance. However, it never states when to call this tool versus list_wissen, find_by_keyword, or get_ai_page — the choice is left to inference.

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