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

Annotations already declare readOnlyHint and destructiveHint, and the description is fully consistent with them. It adds meaningful behavioral context by enumerating what information is returned and prescribing the follow-up action when the balance is insufficient, which is genuinely useful for agent behavior.

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 well-structured: returned fields are front-loaded, and the conditional action follows clearly. The only real inefficiency is that the English sentence largely duplicates the German sentence, adding length without new information.

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?

There is no output schema, so the description carries the burden of explaining the result, and it does so by listing the key return values: balance, daily limit, reset time, and pricing model. For a read-only tool with one optional parameter, an agent has enough information to invoke it and act on the result.

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?

There is one optional 'reasoning' parameter with 0% schema description coverage, and the description does not explain it. The name is self-explanatory and the parameter is optional, so the gap is minor, but the description still adds no semantic value beyond what the schema field name implies.

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 opens with a specific verb ('Liefert' / 'Returns') and names the exact resource: the current wallet status, including balance, daily cap, reset time, and pricing model. It is clearly distinguishable from the sibling wallet_topup_link, which is a top-up action rather than a read-only status check.

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 explicitly states the decision rule: if the balance is below the planned sending costs, call wallet_topup_link and give the human the top-up link. This gives the agent a concrete condition for choosing the relevant alternative, going beyond a vague 'use when needed'.

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