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

Annotations already declare readOnlyHint=false, idempotentHint=true and destructiveHint=true, so the safe/unsafe profile is covered. The description adds genuine scope context ('Does not install an integration or prove provider support') and the returned contract, but never explains the destructive side — that previously stored answers are overwritten or that an empty checkout_domains clears storage — which is the one thing an agent invoking a destructive-hinted tool most needs spelled out.

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 sentences, front-loaded with the action and its data payload, followed by limits and a precondition. Slightly redundant in the 'does not install / activation are separate' pairing, but nothing is padding.

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?

There is no output schema, and the description usefully summarizes the return as the reviewed server SDK success-callback contract, plus it states the connected-site prerequisite. The remaining shortfall is the absence of any note on overwrite semantics for a tool flagged destructive.

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 100% with per-field descriptions and three enums, so the schema carries parameter meaning. The description names only a subset of the six fields (payment provider, landing type/route, checkout domains) and adds no format or constraint detail beyond the schema, so the baseline 3 is correct.

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 (Saves) plus the exact resource (checkout and landing answers) and enumerates the fields involved (payment provider, landing type/route, checkout domains), then names the return value. It also draws a boundary against adjacent operations ('Does not install an integration'), which lets an agent separate it from stage_conversion_installation or verify_install without opening a schema.

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?

Gives a clear precondition ('Requires a connected site') and states what this step is not, noting approval and activation are separate. It does not, however, name a specific alternative tool or spell out the when-not scenario, so an agent still infers routing rather than being told it.

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