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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false, but the description adds significant behavioral detail beyond that: the two pipeline routes, the availability of verification_error{stage,detail}, the semantic difference between could_not_verify and unsupported, and the fact that the tool replaces 4–6 sequential calls. No contradiction with annotations.

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 long but information-dense and well-structured. It front-loads with natural-language examples for quick recognition, then explains scope, routing, return values, and warnings. Every sentence carries meaningful content, though the length could be trimmed slightly without losing essential guidance.

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 fully carries the burden of explaining return values. It enumerates all six verdicts, explains the meaning of could_not_verify and unsupported, mentions the citation format (pipeworx://), and describes routing for both financial and non-financial claims. The description is complete for a complex verification tool with 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?

The input schema already provides 100% parameter description coverage for both claim and tolerance_pct, including tolerance ranges, default behavior, and override for hallucination detection. The tool description does not add parameter-level meaning beyond the schema; it only gives broader pipeline context. Per the baseline for high schema coverage, 3 is appropriate.

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 clearly states the tool's purpose: natural-language claim verification that returns a verdict. It opens with concrete example phrasings ('fact check', 'verify the claim that…'), names the resource (factual claims), and distinguishes itself from sibling tools by describing its two routing paths (SEC EDGAR structured path vs. general grounded fallback) and noting it replaces 4–6 sequential calls.

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 explicitly states when to use it: 'Use whenever the agent needs to check whether something a user said is factually correct.' It also provides routing guidance (financial vs. non-financial claims) and warns callers about the crucial distinction between could_not_verify and unsupported, telling them not to treat could_not_verify as evidence. This gives clear when-to-use and when-not-to-misinterpret guidance.

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