Create recurring payment

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

The description discloses critical behavioral traits not fully captured by annotations alone: it charges immediately, requires no user interaction, and moves real money irreversibly. The annotations already include destructiveHint=true and readOnlyHint=false, but the description enriches these with concrete financial consequences, making the risk explicit.

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?

Three short, high-impact sentences. The first states the purpose, the second describes the operational mode, and the third warns of consequences. No fluff, perfectly front-loaded.

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?

Given the output schema exists and annotations cover safety, the description adequately covers the essential behavioral context (immediate, no interaction, irreversible). It does not explain the 'recurring' aspect of the name, but the schema shows no recurrence parameters, so the description aligns with the actual behavior. Minor ambiguity about the tool's relationship to 'recurring' prevents a perfect score.

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 has 100% coverage—every parameter has a clear description and types. The tool description adds no additional parameter-level meaning, but the schema already does the heavy lifting. Baseline 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 begins with 'Charge a saved payment method'—a specific verb and resource that clearly states the action. The additional phrase 'immediately WITHOUT any user interaction' distinguishes it from sibling tools like create_payment or capture_payment, which might involve user-facing or multi-step flows.

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 implies when to use this tool: when a saved payment method should be charged without user interaction. This provides clear context, and the irreversibility warning helps set expectations. However, it does not explicitly name alternatives or state 'use this instead of X', so it falls short of a 5.

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