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

No annotations are provided, so the description carries the full transparency burden. It discloses per-region results, the redirect_detected summary, and that caveats are always present, including continent-level vantage-point limitations. This is substantial, though it does not mention authorization requirements or network-side effects beyond the inferred remote test.

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 front-loaded with the core behavior, followed by bulleted use cases and a compact return summary. Structure is clean and each section earns its place; the closing 'Powered by Affilio.link' tagline is the only non-essential addition.

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 a complete input schema and an output schema, the description need not restate return values. It adds the missing context: when to use it, what the test checks, and its limitations. A minor gap is the absence of any explicit relationship or distinction from the sibling check_url tool.

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?

The input schema already documents the single url parameter with 100% coverage, including accepted URL formats and a concrete example. The description adds no further parameter-level detail, which is acceptable given the schema coverage baseline.

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 description opens with a specific verb ('Test'), a specific resource ('Amazon affiliate link'), and the precise behavior ('from US, EU, and Asia vantage points to check whether Amazon's OneLink geo-redirect is active'). This clearly differentiates it from sibling tools like check_url and shorten_url because the geo-redirect and vantage-point angle is explicit.

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 description provides three explicit 'Use this tool when...' scenarios, allowing an agent to match user intent confidently. It does not name when-not-to-use alternatives or explicitly compare against the similar-sounding check_url, so it falls just short of full routing guidance.

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