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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so safety basics are covered. The description adds a critical security rule ('Never collect card or bank details') and clarifies that it operates on accepted quotes, which is valuable context beyond the annotations. It does not disclose return format, but an output schema exists.

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, front-loaded with the key purpose and followed by a clear safety rule. There is minimal waste, though the first sentence is a fragment ('Invoices for...') rather than a complete clause, which slightly reduces clarity.

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?

Given the simplicity (one parameter), rich annotations, and presence of an output schema, the description provides sufficient context to call the tool correctly. It could explicitly state that it returns a payment link URL and when to use it over get_my_quote, but otherwise it is complete.

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%, and the single parameter quoteLink is fully documented in the schema with a warning not to guess. The description adds no parameter-specific information beyond what the schema already provides, so the baseline 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 states that the tool returns invoices for an accepted Kolmo quote, including amount, status, and the payment page. The verb is implicit (returns/retrieves), but the resource and scope are clear. It distinguishes from get_my_quote by focusing on accepted quotes and payment details, though it doesn't name the sibling explicitly.

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 phrase 'for an accepted Kolmo quote' implies a usage condition, but there is no explicit guidance on when to use this tool versus alternatives like get_my_quote or respond_to_quote. The rule 'Never collect card or bank details' is a behavioral constraint, not usage guidance.

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