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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint, so the description doesn't need to repeat safety. It adds real behavioral value by explaining that could_not_verify means the check did not happen, carries verification_error{stage,detail}, and must not be presented as evidence. It also mentions performance characteristics (replaces 4–6 sequential calls) and exact percent-delta math, which are meaningful beyond the structured 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 dense but front-loaded with trigger phrases and a clear purpose statement. The later parts about verdict definitions and the 'IMPORTANT for callers' note are useful but could be slightly tightened; overall every sentence earns its place.

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 claim-verification tool with no output schema, the description adequately explains what returns: a verdict enum, the actual value with a pipeworx:// citation, and reasoning. It also explains the failure mode (could_not_verify vs unsupported). It lacks exhaustive detail on the grounded pipeline's source routing, but that is internal behavior an agent doesn't strictly need to invoke the tool correctly.

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 schema already covers 100% of both parameters with useful descriptions and examples. The description adds context about tolerance_pct's effect on grading and the default cap of 5, which reinforces but doesn't fundamentally extend the schema. Baseline 3 is appropriate because 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?

The description opens with explicit natural-language trigger phrases and identifies the tool's core action: verifying the truth of a claim against authoritative sources. It also distinguishes the two internal paths (SEC EDGAR/XBRL for company-financial claims, grounded pipeline for any other factual claim), which separates it from siblings like resolve_entity or ask_pipeworx_grounded.

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?

It explicitly says to use whenever the agent needs to check whether something a user said is factually correct, and it names the exception path: company-financial claims go through the SEC EDGAR + XBRL fast path, while any other factual claim falls through to the grounded pipeline. It also tells callers what the verdicts mean and which verdict should not be shown as evidence.

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