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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds context beyond them: the operation is free, keyless, and scoped to publicly reachable pages, plus a hint about a free daily limit being liftable via api_key (in the schema). It does not describe output shape beyond "funnel map," but that is largely the annotations' remaining gap rather than a contradiction.

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 capability and immediately followed by value/return information. The closing clause about nodes noting what a connected check can verify is slightly abstract but earns its place by signaling the funnel map's cross-references.

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 carries the burden of explaining what comes back, and it does so at a high level (a funnel map whose nodes link to verifiable checks). Combined with the schema's rate-limit note, an agent has enough to call this correctly, though the exact shape of the returned map remains unspecified.

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%, including the url example and the api_key rate-limit explanation, so the schema does the heavy lifting. The description adds only that the target must be a public site, which is useful but marginal beyond the schema.

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 concrete verb ("detects") and a well-scoped resource (the revenue stack / funnel map of a public site), and enumerates the detection categories (payment processor, CRM, email, booking, analytics, ad pixels). It stops short of naming which sibling to use instead, so it is clear but not sibling-differentiating.

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?

"Free and needs no key" gives a cost/auth signal that helps an agent decide whether to call it, and the url-based input implies the use case. But there is no explicit when-to-use versus run_revenue_check or get_latest_findings, so the routing decision is left to inference.

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