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

Annotations already declare read-only, idempotent, open-world, and non-destructive behavior. The description adds substantial context beyond this: the structured SEC EDGAR/XBRL path for financial claims, the grounded pipeline fallback, return verdict values, and crucial semantics around 'could_not_verify' (meaning the check didn't happen) vs. 'unsupported'. This is rich, non-redundant behavioral transparency.

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 well-structured: it starts with natural-language examples, then explains the pipeline, return values, error semantics, and replacements. Every sentence provides useful information, though a few could be tightened. Overall it is appropriately sized for the tool's complexity and front-loaded with actionable examples.

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?

Given the tool's complexity (two paths, multiple verdicts, error states), the description is exceptionally complete. It covers return values, error semantics, the difference between 'could_not_verify' and 'unsupported', and even explains why it replaces multiple sequential calls. No output schema exists, so this description carries full responsibility and does so admirably.

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%, so the baseline is 3. The description itself does not add parameter-specific semantics; all parameter details (e.g., tolerance_pct override and default) are already fully described in the input schema. No additional meaning is provided in the description beyond what the schema supplies.

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 uses a specific verb phrase ('natural-language claim verification') and defines the resource (fact-checking against authoritative sources). It clearly distinguishes from sibling tools by focusing on 'fact check' / 'verify the claim' and explicitly mentions it replaces 4–6 sequential calls, making it the go-to tool for claim validation.

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: 'Use whenever the agent needs to check whether something a user said is factually correct.' It also differentiates internal routing for company-financial claims vs. other factual claims, giving clear context. However, it does not explicitly name alternative tools or provide when-not-to-use scenarios, so it stops short of a perfect 5.

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