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

Annotations already declare readOnly/openWorld/idempotent/non-destructive. The description adds valuable behavioral context: safe polling, status transitions, exact returned payload, and a clear statement that no payment or billing data is ever returned. This goes well beyond the annotation baseline.

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 dense but every sentence contributes: purpose, mandatory sequencing, trust boundary, polling guidance, return payload, customer-facing instructions, and failed-case handling. It is well-organized and front-loaded with the core purpose.

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?

With no output schema, the description carries full responsibility for explaining return values, and it does so thoroughly: status values, the esim block, install_instructions, escalation block, and the absence of payment data. All necessary behavior is covered.

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 description coverage is 100% and already explains that session_id is the Stripe checkout session id returned by create_checkout, including the 'cs_' prefix. The description reinforces this provenance but does not add meaningfully new parameter-level detail, so 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 states a specific action and resource: check the status of a Stripe checkout session created by `create_checkout`. It clearly distinguishes this tool from siblings by focusing on order status polling and explicitly references the related creation tool.

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 gives explicit when-to-use guidance: MUST be called after sending payment_url, never trust user claims of payment, safe to poll, and what to do with delivered/failed results. This is direct operational guidance that leaves little ambiguity.

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