firestarter_payment_method

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

Beyond the annotations, the description adds meaningful output and channel details: "Returns a no-login Stripe setup link (works from any channel - WhatsApp, Slack, Telegram) plus a dashboard link." It also clarifies that the card is not needed until order is parked at awaiting_payment_method. However, it does not explicitly describe potential side effects beyond generating a link, despite readOnlyHint=false suggesting mutating 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 front-loaded with the core purpose in the first sentence, then logically organized into warnings, usage triggers, and output details. Every sentence carries distinct information—order constraint, exclusions, when-to-use, and return format—without fluff or repetition that pads length.

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 no output schema and sparse annotations, the description covers all necessary context: what it does, when to use it, when not to, how it fits into the broader purchase flow (after firestarter_execute, before awaiting_payment_method), expected output format (Stripe link, dashboard link), and cross-channel compatibility. This is sufficient for an agent to successfully select and invoke the tool.

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 tool has zero parameters, so the schema is trivially 100% covered and the description does not need to describe parameter syntax. According to the rubric, 0 params earns a baseline of 4. The description adds no parameter-specific information, which is appropriate here.

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 verb+resource: "Check the buyer's payment method status and get a link to add or update their card." It also clearly differentiates this tool from siblings by emphasizing that the card is the "LAST step of a purchase, NOT a precondition," connecting it to purchasing flow context unlike other tools.

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?

Provides explicit when-to-use guidance: "Use this tool when the buyer asks about payment or an order is waiting on a card." It also gives explicit when-not-to-use: "Do NOT collect a card up front just to browse, quote, or compare shipping — none of those need one." It even names the prerequisite tool firestarter_execute and the required step of letting the buyer pick shipping_option_index before card collection.

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