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

Annotations already state destructiveHint=true and readOnlyHint=false, so the destructive nature is covered. The description adds one useful behavioral detail: cancellation releases the reserved amount. However, it does not discuss irreversibility, permissions, or what happens when no matching scheduled send exists, so the addition is modest.

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 two short bilingual sentences with no wasted words. It front-loads the main action and the cancellation side effect, and it avoids repeating schema-level parameter details.

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 dual-mode tool with no required top-level parameters and no output schema, the description is minimal: it does not state that action is practically required, describe list versus cancel responses, or clarify that cancel is the destructive branch. The schema compensates for some of this, so the description is adequate but has clear gaps.

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?

The input schema already describes action, dryRun, scheduleId, and statusFilter with 80% coverage. The tool description adds little parameter-level meaning beyond connecting cancellation to the release of the reserved amount. With high schema coverage, a baseline of 3 is appropriate.

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 uses specific verbs ('listet auf', 'bricht ab') and a clear resource ('geplanten Sendungen des Partners'), and adds a meaningful side effect ('reservierte Summe wird freigegeben'). It clearly distinguishes the list and cancel behaviors, so an agent can tell what this tool does without relying on the name alone.

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 choose this tool over sibling tools such as letter_schedule or order_cancel, and it does not mention exclusions, prerequisites, or alternative tools. The intended use is only implied by the name and action enum.

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