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

Annotations already declare readOnlyHint=true and destructiveHint=false, but the description adds behavioral context beyond that: 'no auth, no state changes, no charges' and 'Public read-only.' These details reassure the agent about side-effect-free operation and access requirements. No contradictions with annotations.

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 consists of two sentences that pack purpose, safety, and prerequisite into under 30 words. It is front-loaded with the primary function and avoids redundancy with the schema or annotations.

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 is simple (one required parameter, read-only, output URL), and the description covers purpose, prerequisite, and safety. With an output schema present and rich annotations, no additional return-format details are needed. The combination of schema, annotations, and description fully supports correct usage.

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 input schema has 100% coverage with a detailed description of product_key, including examples. The tool description adds no new semantic information about the parameter; it only refers to 'a selected offering,' which is already captured in the schema. Therefore, a baseline score of 3 is appropriate.

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 'Return' and identifies the resource as 'the first-party Cannon Studio checkout or inquiry URL' for a selected offering, which clearly distinguishes it from sibling tools like list_offerings or get_pricing_context. The scope is explicit: it's about generating a URL, not modifying or listing.

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 explicitly instructs to use list_offerings first to get a valid product_key, providing a clear prerequisite and sequence. It also states 'Public read-only: no auth, no state changes, no charges,' which sets expectations for safe usage conditions, but it does not enumerate alternative tools or when to avoid this one.

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