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

Annotations declare readOnlyHint=false and destructiveHint=false, which would be puzzling for a lookup; the description usefully explains this by disclosing that the call consumes one prepaid credit. It stops short of covering what happens on failure (is the credit still charged?), whether results are cached, or any rate/credit-exhaustion behavior.

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?

A single front-loaded sentence with zero filler; every clause carries information (return content, scope, cost). It is arguably too terse for a tool that consumes a paid resource, but nothing is wasted.

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, so the description carries the burden of describing the return value, yet 'live web technologies' gives no shape (list, grouped object, confidence fields). For a credit-consuming call with an undocumented liveOnly flag and no error semantics, the definition leaves meaningful gaps an agent would need to call it confidently.

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 only 33%: creditKey is documented in the schema, but 'domain' and 'liveOnly' are bare. The description partially compensates — 'one domain' maps to the domain parameter and 'live web technologies' hints at the liveOnly filter — but it never explains what liveOnly=false returns or what happens when a domain has no detected technologies.

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 states a specific verb and resource ('Returns live web technologies') scoped to 'one domain', so the agent knows exactly what it gets. It does not explicitly differentiate itself from the free 'domain-lookup' sibling, so the paid/credit-based distinction is only implied by the tool name and the credit mention.

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?

Mentioning 'using one prepaid credit' signals a cost tradeoff, which implicitly tells the agent to weigh this against free lookups. However, it never names an alternative tool, never states when this paid variant is preferred, and never states the prerequisite that a credit key must be purchased first (that only appears in the schema).

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