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

Beyond the annotations (readOnly, idempotent), the description richly discloses behavior: it details return verdicts (confirmed, refuted, etc.), the meaning of could_not_verify and unsupported, that could_not_verify must not be treated as evidence for/against, and that evidence includes verbatim citations and reasoning. This is substantial added transparency for a complex verification tool.

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 quite long but densely packed with necessary information. It is front-loaded with example queries and organized logically: purpose, usage, pipeline routing, return format, edge cases, and efficiency note. Every sentence earns its place, though it could be slightly tightened.

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?

With no output schema, the description fully explains the return value (verdict, actual value with citation, reasoning) and covers edge cases like could_not_verify and unsupported in detail. It also addresses both financial and non-financial claim paths, making it complete for a tool of this complexity.

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% for the two parameters, so the baseline is 3. The description adds meaning by explaining how tolerance_pct interacts with claim wording and suggests setting 1–2 for hallucination detection, which is valuable beyond the schema. This warrants a 4.

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 defines the tool as natural-language claim verification against authoritative sources, with verb 'validate' and resource 'claim'. It gives explicit example queries and distinguishes itself from generic Q&A by detailing specialized financial vs. other factual claim pipelines, and by 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 explains how different claim types are routed (financial vs. other), which is strong usage context. However, it does not explicitly mention exclusions or alternatives, so it falls short of a 5.

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