Simulate a tap

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds genuine value beyond that: no analytics recording and no billing impact, plus an enumeration of the decision outcomes returned. It doesn't explain the response shape in more detail, but that's minor here.

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 action and outcome list, then the key 'nothing recorded or billed' reassurance and the ua hint. No filler.

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?

With no output schema, the description usefully enumerates the possible decision outcomes, which compensates well. The remaining gap is the url/slug selection rule, which an agent must infer from the schema alone.

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%, so the schema already documents all three parameters. The description only restates that ua is a preset or raw User-Agent, mirroring the schema. It misses a chance to clarify the url-vs-slug relationship, which the schema does not state explicitly.

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?

Specific verb and resource: 'Dry-run one tap on a link' with the outcomes it evaluates (redirect, in-app-browser escape page, store, preview card). It's clearly distinguishable from siblings in spirit, but it never names near-neighbors like trace_tap or check_link to disambiguate.

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 dry-run framing and 'Nothing is recorded or billed' imply the testing use case, but there's no explicit when-to-use or when-not-to-use, and no mention of trace_tap (the likely live-tracing alternative) or check_link. Usage is inferred rather than stated.

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