decode_paybysquare

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

No annotations are provided, so the description carries the disclosure burden. It clearly states the input format and that payment data is returned, but it does not explain error behavior, output structure, or any processing limitations. This is minimal but acceptable for a simple decoding tool.

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?

A single, front-loaded sentence conveys the action, input format, and result without filler. Every part earns its place.

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 one simple parameter and no output schema, so the description should clarify what 'payment data' contains for downstream use. The current phrase is functional but vague; an agent may not know what fields or format to expect from the decoded data.

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%, so the schema already documents imageBase64 adequately. The description's reference to 'base64-encoded PNG image' adds no meaning beyond what the parameter schema already provides.

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?

Description states a specific verb ('Decode'), a clear resource ('PayBySquare QR code'), and the input format ('base64-encoded PNG image'). This distinguishes it from sibling generate_paybysquare, which creates rather than decodes.

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?

Usage is implied by the verb and resource: the tool is for decoding a base64-encoded PayBySquare QR image. However, it does not explicitly mention alternatives like generate_paybysquare, check_compliance, or verify_roundtrip, nor does it say 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.