Generate QR Code

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, so the safety profile is well-covered. The description adds value by disclosing the payment cost ($0.01 USDC) which is a genuine behavioral trait beyond annotations. It also reveals the return format (PNG base64). No contradiction with annotations found.

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?

Three short sentences with zero waste. Each sentence earns its place: purpose, output format, and cost. Information is front-loaded with the core purpose stated first.

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 relatively simple generate tool, the description is complete: it states purpose, output format, and cost. The output schema exists, so return values don't need elaboration. The _payment parameter is complex but already thoroughly documented in the schema itself. Could mention pagination/limits but none apply to QR generation.

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 all 4 parameters are already documented in the schema, including the size default, format enum, and _payment instructions. The description adds the output-format detail (PNG base64) and cost context, but doesn't add meaning beyond the schema's parameter descriptions. Baseline 3 is appropriate given complete schema coverage.

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 uses a specific verb+resource ('Generate a QR code') with clear scope ('from text or URL'). It also states the output format (PNG image as base64) and distinguishes from the sibling tool qr.generate_styled by implying standard QR generation. Purpose is fully clear.

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 implies usage context (encode text/URL into QR) but offers no explicit when-to-use vs alternatives guidance. There's no mention of when to use qr.generate vs qr.generate_styled, or exclusions. The cost mention ($0.01 USDC on Base) adds a practical usage signal but not comparison guidance.

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