Wait for checkout

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

Annotations already indicate readOnlyHint: true and openWorldHint: true. The description adds value by specifying the return shape ({ status, terminal, timed_out }), explaining timeout behavior ('returns timed_out:true rather than being killed'), and stating the required scope. This goes beyond annotations, though it doesn't detail progress emission mechanisms.

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 extremely concise: two sentences that cover purpose, behavior, return shape, and scope. Every sentence is necessary and front-loaded with the core action. No wasted words.

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 parameters, output schema present, annotations provided), the description covers the essential aspects: core behavior, return shape, timeout semantics, and required scope. It omits details about progress emission and error handling for invalid checkout_id, but these are minor gaps given the context.

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 100%, so the schema already documents both parameters well. The description adds contextual meaning for timeout_seconds by clarifying that exceeding it returns timed_out:true instead of an error, which is valuable beyond the schema's description of min/max/default.

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 the tool's purpose: 'Wait server-side for a checkout to reach a terminal status, emitting progress.' It uses a specific verb ('wait') and resource ('checkout'), and distinguishes itself from sibling tools by explicitly contrasting with 'no client-side polling.' This makes the purpose unambiguous and distinct.

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 usage guidance by contrasting with polling ('One call — no client-side polling') and specifying the required scope ('merchant_read'). However, it does not explicitly list alternative tools or conditions when not to use this tool, which would enhance clarity.

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