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

Annotations only carry readOnlyHint=true, so the description usefully adds that the endpoint returns organisations only by default and that include_persons must be set to receive individual persons. This is meaningful non-obvious behavioural context beyond the annotations.

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 tight sentences, front-loaded with the resource and categories, then the key default-vs-expanded behaviour and the raw endpoint. 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?

For an 11-parameter read tool with no output schema and only a readOnlyHint annotation, the description covers the essential quirk (default organisation-only results). It could say more about pagination or the shape of results, but it is adequate.

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%, so all 11 parameters are already documented, including the include_persons default and category_id values. The description restates include_persons rather than adding syntax or format detail 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?

States a specific verb (List) and resource (contacts) and enumerates the contact categories returned, so the agent knows exactly what this fetches. It doesn't explicitly contrast itself with the sibling sevdesk_get_contact, but the list-vs-get distinction is clear from the name and description.

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 notes the default behaviour and how include_persons changes results, which is useful invocation guidance. However, it gives no when-to-use direction relative to alternatives like sevdesk_get_contact or the list_communication_ways siblings, leaving routing partly to inference.

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