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

Annotations only carry title and destructiveHint=true, so the description must shoulder most of the behavioral load. It usefully discloses the side effect (creates a payable link) and the return value (a URL), but says nothing about idempotency handling, expiry semantics, or permissions.

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, front-loaded sentences that lead with the action and the outcome. The capitalized emphasis is slightly noisy but no sentence is wasted.

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 creation tool with 11 mostly-optional parameters, full schema documentation, and no output schema, the description covers the essential outcome (hosted link plus URL). Remaining gaps (idempotency, auth, expiry) are minor given the rich schema.

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% across all 11 parameters, including nuances like minor units for amount, so the schema already does the heavy lifting. The description adds no parameter-level detail beyond that, making the baseline 3 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 ('CREATES a hosted Payment Link'), clarifies the financial intent ('COLLECT MONEY'), and names the backing endpoint (POST /payment-links). It separates itself from checkout_create_payment by emphasizing the hosted, shareable link, though it does not name siblings 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?

Usage is implied by 'Returns a URL to share with the customer', which suggests the send-a-link scenario, but there is no explicit when-to-use versus checkout_create_payment or other collection siblings, and no preconditions (auth, idempotency) are stated.

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