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

With no annotations, the description carries the full transparency burden. It discloses a required header ('x-anygas-receipt: 1'), the conditional trigger (IF Robyn refuses), and a critical limitation: 'It proves the refusal HAPPENED; it does not claim the refusal was correct.' This is meaningful behavioral context, though it omits return format and authentication requirements.

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 action and remains focused. The extended rationale about blame and proving external blockage is helpful but slightly verbose; still, each sentence contributes to understanding the tool's value and proper use.

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?

The tool has a single parameter, no output schema, and no annotations, so the description must cover the full context. It explains the setup, when it applies, and a key semantic limit, but it does not describe the verification result format, failure behavior, or how to interpret the outcome, leaving notable gaps for a no-output-schema 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 schema covers 100% of the single required parameter 'receipt,' described as 'the full refusalReceipt object as returned.' The description adds context about the receipt's contents (what was asked, when, and why) and its purpose, but the schema already provides the essential semantics, so the value added is marginal.

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 starts with 'Check a signed refusal receipt,' which clearly identifies the tool's primary action and target resource. It distinguishes this tool from siblings by focusing specifically on refusal receipts and explaining their evidentiary role, making its purpose unmistakable.

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 explains when this tool is relevant: when Robyn refuses a request and the provider denies, and it emphasizes that the receipt proves external blockage versus agent failure. It provides clear context for use, though it does not explicitly name alternative tools or state when not to use it.

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