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

Annotations already declare readOnlyHint=true and openWorldHint=true, but the description adds real value beyond them: it discloses the exact data sources probed and states that blocked, unreachable, nonexistent, and no_signals pages are not charged. Cost behavior is agent-relevant context that structured fields do not carry.

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 dense sentences with no filler, front-loaded on the detection scope and followed by the billing caveat. Slightly clause-heavy in the first sentence, but every clause conveys distinct information.

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 single-parameter, read-only detection tool with no output schema, the description covers what is scanned, the scope constraints, and the cost exclusions. It could say more about the shape of the result, but the essential call-time information is present.

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 100% and the single 'domain' parameter is fully documented there (no scheme, path, or port). The description's 'Single domain' adds only a marginal reinforcement of what the schema already establishes, so the baseline 3 applies.

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 (Detect) and enumerates the exact resources examined: technologies, ad pixels, DNS signals from home page, HTTP headers, cookies, and up to two GTM containers. An agent immediately knows what it gets and the scope ('Single domain'), and the only sibling (get_company_open_jobs) is an unrelated domain, so no disambiguation is needed.

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 implies when the tool applies but never says so explicitly. 'Single domain' and 'No browser JavaScript execution' are meaningful constraints that steer selection (no JS-rendered detection), yet there is no explicit when-to-use/when-not framing or named alternative for the JS-rendered case.

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