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

With no annotations, the description must carry behavioral disclosure, and it does reveal a real-world consequence: this is a pay-per-use tool costing 5.0 USDC on Base and producing a report with cited web sources. However, it does not describe output format, latency, side effects, or any limitations, and 'PREMIUM' is a label rather than a behavioral explanation.

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 very short and front-loads the primary purpose before cost details. The phrasing is fragmentary ('input=topic.', '[x402: 5.0 USDC on Base, pay-per-use]') but each portion earns its place. The 'PREMIUM:' prefix is mostly marketign labeling rather than functional 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 paid tool, the description covers the critical invocation facts: pass a topic, receive a cited research report, and pay 5 USDC. Missing are output format details, explicit warning that spending money requires user consent, and guidance about which sibling tools are cheaper, free, or more appropriate for lighter research needs. It is adequate for invocation but not rich enough for confident routing among similar report tools.

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's parameter description is only 'service input,' so the description's 'input=topic' is the meaningful explanation. Since there is exactly one parameter, this is sufficient for an agent to construct a valid call. It does not add formatting constraints, but none are needed for a free-form topic string.

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 communicates the deliverable: a full research report with cited web sources, and tells the agent the input is a topic. It is distinct from generic siblings like 'research' or 'report' by emphasizing 'deep' and 'cited web sources,' though it lacks an explicit verb like 'generates.'

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?

There is no statement of when to choose this tool over siblings such as 'research,' 'report,' 'fact-check,' or 'market-intelligence.' The only usage cue is 'input=topic,' which tells what to pass but not which scenario warrants the premium tool. It also does not mention exclusions, cheaper alternatives, or when a non-preMIUM tool would suffice.

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