Add payment method (card on file)

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

With no annotations provided, the description carries full burden. It discloses that the raw card is sent only to the PCI-compliant clearing provider and never stored, which is a key behavioral trait. It also implies a verification step. However, it does not mention what happens on failure, whether existing methods are replaced, or any rate limits.

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?

Two concise sentences with the core action front-loaded. The alternative is mentioned at the end, and there is zero fluff. Every sentence contributes to the agent's understanding.

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 complexity (nested card object, optional plan, security implications), the description covers the essential purpose, the alternative, and the security model. Missing are details about the response format or any prerequisites, but the description is sufficient for an agent to invoke it correctly with the required parameters.

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 coverage is only 33% (only the card object is described). The description does not elaborate on the meaning of organizationName or the optional plan parameter. The card object itself is well-described in the schema, so the description adds little parameter-specific value beyond the schema.

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 action: verify a card with Tranzila and save its token to an organization. It distinguishes itself from the hosted alternative by naming the sibling tool (gambot_create_payment_link) and explaining the difference (agent vs customer entering the card).

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?

Explicitly provides a when-to-use scenario ('so an AI agent with the customer's card can put a payment method on file without the hosted page') and a clear alternative ('For a hosted alternative... use gambot_create_payment_link'). This leaves no ambiguity about when to select this tool.

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