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

The description states 'This reads state and moves nothing,' which aligns perfectly with the readOnlyHint, idempotentHint, and destructiveHint annotations. It goes beyond annotations by explaining the meaning of each possible status (funded, completed, gone home, expired) and how they relate to the money, adding valuable behavioral context for the agent.

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 longer than average but each sentence contributes meaningful context, explaining the statuses and usage. It is front-loaded with the core purpose and then expands on details. While not maximally concise, it is well-organized and avoids 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?

For a tool with only two parameters and no output schema, the description is exceptionally complete. It covers the purpose, the meaning of each status, the exact usage pattern (polling after mail click), and the read-only nature. There is nothing an agent needs to call it correctly that is missing.

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 schema already covers both parameters with descriptions (100% coverage). The description adds marginal value by emphasizing that order_ref comes from checkout_intent, but this is already stated in the schema's parameter description. Therefore, the description does not significantly enhance understanding 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 clearly states the tool's purpose: checking the status of an order and explaining what each status means for the money. It names the specific resource (order) and the action (check status), and it distinguishes itself from sibling tools like checkout_intent by focusing on reading state rather than creating intents.

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 usage guidance: pass the shop and order_ref returned by checkout_intent, and poll after the human says they clicked the mail. It also notes that the tool reads state and moves nothing, implying it should not be used for actions. However, it does not explicitly name alternative tools for different scenarios, so it falls just short of a 5.

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