sanity_check

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

With no annotations, the description carries the full burden and does well: it discloses the verdict taxonomy, that confidence_score is raw consistency, the interpretation policy, auth options (x402 or SANITY_API_KEY), and 429/retry_after rate-limit behavior. It stops short of describing the return payload beyond pointing at `data`.

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?

Densely front-loaded: purpose first, then verdicts, then the action policy, then auth and rate limits, with no filler sentences. It is packed into a few clauses, which is efficient though slightly terse.

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, and the description covers the key return semantics (verdict values, confidence_score meaning) plus auth and rate-limit handling. It leaves the structure of `data` unexplained, but for a single-claim verifier the essentials are 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%, so mode, claim, and context semantics are already fully documented in the schema; the description adds no parameter-level detail beyond what is there. Baseline 3 applies when the schema does the heavy lifting.

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 and resource ("Verify one claim") and the "one claim" scoping implicitly distinguishes it from the sibling sanity_check_batch. It never names that sibling, so the differentiation is inferable rather than explicit.

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?

Provides an explicit decision policy mapping each verdict to an action (act on supported; treat unsupported/insufficient_evidence as unverified; reject contradicted), which is clear when-to-use guidance. It does not say when to prefer the batch sibling or when verification is unnecessary, so no exclusions are given.

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