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

readOnlyHint=true already tells the agent this is a safe read. The description adds the upstream endpoint mapping (GET /CommunicationWay), which is mild context, but says nothing about paging behavior, sorting, or what the payload contains. With annotations covering safety, this is adequate but thin.

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?

One sentence plus the endpoint reference; the parenthetical clarification of 'communication ways' is front-loaded where it matters, and no words are wasted.

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 should hint at the return shape or volume, but it only says 'List'. Pagination-relevant parameters (limit, offset, count_all) exist in the schema, so the agent can infer paging, but a one-clause note about the returned collection would round this out.

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% and seven parameters (type, embed, limit, offset, count_all, main_only, contact_id) are all documented in the schema itself. The description only adds 'optionally for one contact', which loosely maps to contact_id, so it contributes nothing beyond the schema baseline.

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) plus resource (communication ways) and immediately disambiguates the jargon by enumerating examples: email addresses, phone and mobile numbers, websites. It also names the contact-scoping option. It does not, however, explicitly differentiate itself from the write-side sibling sevdesk_add_communication_way or from sevdesk_get_contact.

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 phrase 'optionally for one contact' implies the main use case (all communication ways vs. one contact's), which is implied guidance rather than explicit. It never states when to prefer this over sevdesk_get_contact or sevdesk_list_communication_way_keys, and there are no exclusions or prerequisites.

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