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

The description states 'Create a checkout URL' implying a non-read mutation, but annotations declare readOnlyHint=true. This is a direct contradiction, violating transparency. No other behavioral traits are disclosed beyond the contradictory creation claim.

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?

Two sentences with clear structure: purpose then a specific usage instruction. While concise, the first sentence is somewhat cryptic (what is the JWT token reference?). No extraneous words, but could be improved.

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?

With 10 parameters and an output schema, the description only covers a single usage scenario (special TLDs). It does not explain the JWT context, how parameters interact, or the checkout flow. The output schema may cover return values, but operational context is lacking.

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 coverage is 60%, and the description adds no parameter-level meaning. It introduces the concept of a 'raw JWT token' which is not a parameter in the schema, potentially confusing the agent. No parameter values or relationships are explained.

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 creates a checkout URL for available domains using a raw JWT token. The verb-resource pairing is specific and distinct from sibling tools which focus on domain info and pricing.

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 provides explicit guidance for special TLDs: 'do not collect field values in chat; tell the customer what checkout will require.' This is a useful behavioral instruction, though it lacks explicit context on when to use this tool vs alternatives (which are absent among siblings).

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