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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, so the safety profile is fully covered. The description adds valuable behavioral context: it intentionally withholds contact details and explains that the server resolves the recipient from the customer master, so the agent doesn't need the address to send. It also implies the tool returns fields like ID, name, location, and whether an email is stored. No contradiction with 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?

The description is compact and front-loads the core purpose. The capitalized warning is somewhat loud but earns its place because it prevents duplicate creation. The last sentence about contact data is relevant but could be considered slightly redundant; overall it's efficient and well-structured.

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 read-only search tool with a simple schema and no output schema, the description is largely complete: it states what it returns, what it deliberately omits, and how the outputs are used downstream. A minor gap is not enumerating the exact output fields or ordering behavior, but the tool's simplicity and annotation coverage make this acceptable.

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 the schema already documents both 'suche' and 'anzahl' clearly. The description adds a usage nuance: omitting 'suche' returns the most recently created customers, which slightly extends the schema's wording. Beyond that, it doesn't need to add more parameter detail because the schema covers it.

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 verb+resource: it finds customers of the business by name, company, or location and returns their identifier. It clearly distinguishes its purpose from sibling tools like kunde_anlegen by explaining the ID is required by rechnung_anlegen, angebot_anlegen, and auftrag_anlegen. No tautology or ambiguity.

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 gives explicit guidance: search first, then create. It warns against using kunde_anlegen when the existing entry is not found, and explains the consequence (duplicate records with separate invoice history). It also states when not to expect contact data and why, which helps agents decide if this tool is sufficient.

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