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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so the safety profile is covered elsewhere. The description adds real value by promising per-field provenance of the data, which is a behavioral trait no annotation conveys. It says nothing about behavior on an unknown slug or rate limits.

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?

Content is front-loaded and short, but it is delivered twice (German and English), so a monolingual reader consumes duplicated sentences. The bilingual pattern is defensible for a German-market tool, yet it still costs tokens without adding information.

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 usefully names the returned fields and their provenance. Combined with a fully documented single parameter and rich annotations, an agent has enough to call this correctly; only error/empty-result behavior is unaddressed.

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 100% and the single parameter is already documented as the slug from a search result. The description's added contribution is the negative constraint ('nicht der Firmenname'), which is useful but marginal, 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?

Names a specific verb and resource ('Liefert das vollständige Profil eines Unternehmens') and enumerates the returned content (address, services, certificates, register entry, contact, provenance). The required-slug constraint implicitly separates it from the sibling firmen_suchen, though it never names that sibling explicitly.

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?

Gives a concrete prerequisite: the slug must come from a search result, not the company name. That steers the agent to call firmen_suchen first, but the routing is implied rather than stated as an explicit 'use X then Y' instruction, and there are no when-not conditions.

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