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

With no annotations, the description carries the full behavioral burden. It usefully discloses the core guarantee that unverifiable claims are discarded and never returned as truth, and it names the pay-per-use price (0.08 USDC on Base via x402), which is important context. However, the description is truncated mid-word ('and verifie'), never explains failure behavior, latency, or how partial verification is represented, so the behavioral picture is materially incomplete.

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 short, but the opening clause is promotional rather than informative, and the second sentence is visibly truncated, weakening structure and completeness. The useful content is front-loaded, but the truncation prevents a higher score.

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?

No output schema exists, so the description should explain return values; it lists source URL, date, verbatim quote, and verification_score, which is helpful. But the sentence cuts off at 'and verifie', leaving the output contract partially unspecified for a tool with no annotations and no output schema.

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?

There is one parameter and schema description coverage is 100%, so the schema already documents the input fully, including the JSON query form with dominio and max_claims. The description adds no parameter-specific meaning, but baseline 4 applies when there is a single fully documented parameter.

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 that the tool returns machine-verifiable JSON with cited claims and a verification score, but it does so through a marketing frame ('The answer your agent can act on without fear') rather than a plain statement of what the tool does. It never explicitly says it verifies a question or claim, leaving that to the input schema, and it does not distinguish itself from siblings like fact-check or fact-check-quick.

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 explicit when-to-use or when-not-to-use guidance, and no comparison to the many adjacent verification and fact-check siblings. An agent must infer usage entirely from the output description.

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