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

The annotations already declare readOnlyHint=true and destructiveHint=false, so the safe read-only nature is covered. The description adds transparency by enumerating exactly what the tool returns (addresses, category, monthly budget, retention period, letter count), which is valuable because there is no output schema.

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?

The description is a single clear sentence, but the English sentence fully duplicates the German sentence without adding information. This repetition costs tokens without benefit, though the field list is dense and relevant.

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 a tool with no output schema and three undocumented parameters, the description covers the return fields but leaves critical invocation details unaddressed: how to identify the Mandant, whether mandantId or mandantennummer is preferred, and what the optional reasoning parameter is for. It also does not distinguish when to use this versus list/search siblings.

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 0%, and the description does not explain the meaning or usage of mandantId, mandantennummer, or reasoning. The parameter names are somewhat self-explanatory, but the description adds no input guidance, leaving ambiguity especially because no parameters are marked required.

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 clearly states the operation ('Liefert' / 'Returns') and the resource ('einen Mandanten'), and lists the specific data fields returned. It is distinguishable from sibling tools like mandant_list and mandant_search by its singular framing, though it does not explicitly contrast itself with them.

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 provides no guidance on when to use this tool rather than alternatives such as mandant_list or mandant_search. It also fails to state whether callers should supply mandantId or mandantennummer, or when this single-record getter is appropriate.

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