Update a payment link

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

The annotations already declare the mutation profile: readOnlyHint=false, destructiveHint=true, idempotentHint=true, and openWorldHint=true. The description adds a useful behavioral constraint that a live key will be refused, but it does not explain which updates are destructive, how partial updates behave, or any rate limits or permissions beyond the test-key restriction.

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 is two sentences with no filler and places the purpose first, followed by the test-key constraint. It is structurally efficient, though its brevity leaves important gaps that are reflected in other dimensions rather than in wasted language.

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 destructive 8-parameter update tool with only 25% schema description coverage, no output schema, and nested metadata semantics, this description is far too sparse. It does not describe update behavior, field-level effects, return shape, or how omitted versus provided fields are handled.

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 only 25% across 8 parameters, and the description provides no parameter semantics at all. Six parameters are undocumented in the schema and entirely absent from the description, so an agent gets no help understanding fields like quantity, success_url, or collect_name.

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 first sentence, "Update a payment link," restates the tool name and title without adding any distinguishing detail. It does not clarify what kinds of updates are possible or how this differs from create_payment_link, list_payment_links, or pay_links.

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 only guidance is the operational note "Test keys only: refused with a live key." It does not explain when to use this update tool versus alternatives such as creating a new payment link or using pay_links.

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