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

Annotations already declare readOnlyHint=true, and the description adds useful behavioral detail beyond that: ambiguous names return candidates and never a silent selection, and only SEC-registered public companies and funds are covered. This helps the agent predict edge-case behavior without contradicting any annotation.

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 compact and front-loaded, with the core purpose stated in the first sentence. Each subsequent sentence adds distinct value: input forms, returned fields, ambiguity handling, scope boundaries, and intended use case. There is no filler or repeated information.

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?

Since there is no output schema, the description compensates by explicitly listing the returned fields: entity name, CIK, SIC industry, state of incorporation, exchanges/tickers, address, and latest SEC filing. It also covers ambiguity handling and scope exclusions, giving an agent enough information to call the tool and interpret its 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?

The schema description covers 100% of the single parameter and already provides examples of ticker, CIK, and company name. The tool description restates that the query can be a ticker, CIK, or company name but adds no additional parameter semantics beyond the schema, so the baseline of 3 applies.

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 a specific verb-resource pair: 'US public company verification via SEC EDGAR', and enumerates both accepted inputs (ticker, CIK, company name) and returned fields. It also distinguishes itself from siblings by limiting scope to SEC-registered public companies and funds, and explicitly excluding private US companies.

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 gives clear usage context: 'Call for KYB and counterparty due diligence on listed US entities.' It also sets boundaries by stating coverage is limited to SEC-registered public companies and funds only. It does not explicitly name alternative tools like verify_uk_company, so it stops short of a full when-to-use versus alternatives statement.

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