subscriptions__create_checkout_link

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

With no annotations, the description carries the full burden. It discloses that the tool never charges a card and fails closed under certain conditions, but does not mention authentication, rate limits, or side effects beyond creating a session.

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 two sentences, front-loaded with purpose, and every sentence adds value. The bracketed prefix provides context without redundancy.

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's simplicity (2 params, no output schema), the description covers the core behavior and failure conditions well. However, it lacks detail on the response format and authentication prerequisites.

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 0%, so the description should add meaning to parameters. While the parameter names are somewhat self-explanatory, the description only implicitly references plan_id (via 'Draft plans') and does not explicitly describe account_ref or their expected formats.

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 'Prepare a Stripe-hosted subscription Checkout URL', which is a specific verb and resource. It also distinguishes itself from sibling tools like subscriptions__customer_portal_link or subscriptions__record_subscription by focusing on creating a checkout link for new subscriptions.

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 lists failure conditions (draft plans, missing owner approval, etc.) that help the agent know when the tool will not work, but it does not explicitly compare to alternatives or provide guidance on when to use this tool over others.

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