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

Annotations already supply destructiveHint=true, but the description never explains or acknowledges that hint, nor does it describe auth requirements, rate limits, or whether the created link is idempotent. It adds only the notion of 'reusability' and the underlying endpoint, which is modest value beyond the 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?

Two tight sentences with the core purpose front-loaded and no filler. The trailing 'Polar: POST /v1/checkout-links/' endpoint reference is marginally useful for an agent and adds minor noise.

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 five-parameter, fully schema-documented creation tool with no output schema, the description covers the essential purpose and that it yields a reusable URL. It omits any note on the mutation's side effects or the exact response shape, which slightly limits completeness.

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 five parameters are already documented in the schema. The description adds only the 'one or more products' implication, which the array type and schema description already convey; 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?

States a specific verb and resource ('Create a reusable checkout URL for one or more products') and clarifies scope including array-valued products. No sibling creates checkout links, so the agent can immediately distinguish it from the list/get tools around it.

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 'the link you put in a page or an email' gives implied usage context, but there is no explicit when-to-use vs when-not-to-use guidance, no prerequisites (e.g. product ids must exist), and no named alternative to route away from.

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