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

Annotations already establish readOnlyHint=false and destructiveHint=false, so the mutation profile is known. The description adds the useful behavioral fact that the address is validated using country-specific rules. However, it does not disclose upsert semantics, such as whether addressId selects an existing record for update, what happens on validation failure, or whether omitted fields are preserved or overwritten.

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?

Two compact sentences, in German and English, front-load the operation and validation behavior without extraneous detail. The bilingual duplication is justified in a German-context tool and every sentence contributes meaning.

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 12-parameter upsert with no output schema, the description is too thin. It omits create-vs-update selection, country defaulting, validation failure behavior, and any explanation of the listed address attributes. An agent would need to infer or probe the tool to call it correctly in non-trivial cases.

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 only 8%, so the description needed to carry most parameter meaning, but it does not. It only broadly implies that fields like name, street, and city are address-book attributes and that country matters for validation. It fails to explain the create-vs-update role of addressId, the meaning of isDefault, addressType, mandantennummer, or behavior around required fields.

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 states a specific action: 'Creates or updates an address in the partner address book' and adds a distinct behavior, country-specific validation. This clearly separates it from read-only siblings like address_list and address_search_company, and from address_validate, whose exclusive purpose is validation. The bilingual text reinforces the intended resource and operation.

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 makes the usage context clear: call this tool when an address needs to be created or updated in the partner address book. It does not explicitly name alternatives or state when not to use it, such as directing validation-only needs to address_validate. Thus it provides clear context but no exclusions.

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