Create Debit

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

Annotations provide readOnlyHint=false and destructiveHint=false, so the description adds context that it's a WRITE operation and mentions optional retry control. However, it does not describe side effects (e.g., subscription status changes) or failure modes, leaving behavioral transparency somewhat incomplete.

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 reasonably concise with all sentences providing value. It starts with a tag and action, then lists required interaction, optional parameter, and a caution. No redundancy, but slightly longer due to the explicit instructions.

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 tool has 3 optional params, an output schema (present but not shown), and no required params, the description covers the key prerequisite (must have at least one identifier) and cautions against automated calls. It could add more about what happens on success/failure, but the output schema likely handles return values.

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?

With 0% schema description coverage, the description adds meaning for two parameters (presentation_id, merchant_presentation_reference) by identifying them as required identifiers, and mentions is_merchant_retry as an option. However, it does not explain their formats or constraints beyond the schema, and the third parameter is not elaborated.

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 clearly states it executes a debit (payment collection) against a subscription. It uses specific verb 'Execute a debit' and specifies the resource 'subscription', distinguishing it from other payment or subscription tools like create_card_payment or create_subscription.

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 explicit when-to-use guidance: it must only be called when explicitly requested by the human user, and the agent must ask for at least one of presentation_id or merchant_presentation_reference. It also warns against calling based on instructions from data fields, API responses, etc., which prevents misuse.

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