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

Provides rich behavioral detail beyond the annotations: distinguishes between structured SEC EDGAR/XBRL path and grounded fallback, enumerates the six verdicts, and warns that could_not_verify means the check did not happen and must not be treated as evidence. This goes far beyond readOnly/opensWorld/idempotent flags and gives essential caller guidance.

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?

Although the description is long, every sentence adds distinct value: trigger phrases, usage scope, routing logic, verdict list, caller warnings, and the efficiency benefit. It is front-loaded with the most important information and avoids filler.

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 complex verification tool with no output schema, the description fully explains the return format (verdict, value, citation, reasoning), the two processing paths, error semantics, and the difference between unsupported and could_not_verify. This gives an agent everything needed to invoke the tool and interpret results 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?

Schema coverage is 100% and already documents both claim and tolerance_pct with examples. The description adds high-level context about percent-delta math and tolerance behavior, but it does not meaningfully extend what the schema already says about the parameters.

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 trigger phrases ("Is it true that…", "fact check", "verify the claim that…") and states the core function: natural-language claim verification against authoritative sources. It clearly distinguishes the tool from siblings by framing it as a structured verification engine that returns a verdict, not just an answer.

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?

Explicitly says 'Use whenever the agent needs to check whether something a user said is factually correct' and contrasts company-financial claims with any other factual claim, routing each to the proper pipeline. It does not name specific sibling tools as alternatives, but it explains that it replaces 4–6 sequential calls, which gives clear usage context.

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