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

Annotations already declare readOnlyHint=true and openWorldHint=true, and the description adds valuable behavioral detail: ambiguous name searches return candidates and never silently select a company. It also discloses the authoritative data source and the EDGAR coverage boundary, which go beyond what annotations convey.

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: it states the core function, return fields, ambiguity behavior, scope boundary, and use case in a few ordered sentences. Every sentence adds useful information without 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?

With a single parameter and no output schema, the description does the necessary work: it enumerates the returned fields, explains behavior on ambiguous input, and constrains scope. An agent would know what to pass and what to expect from the result.

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% and the schema already explains that query is a ticker, CIK, or company name with examples. The tool description repeats this rather than adding new parameter-level meaning, 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 and resource: 'US public company verification via the SEC EDGAR system.' It clearly distinguishes itself from siblings like verify_uk_company by specifying US jurisdiction and public-company scope, and it enumerates concrete return fields such as CIK, SIC code, and listed exchanges.

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 states the intended use ('Use for KYB and counterparty due diligence on listed US entities') and explicitly defines when NOT to use it ('NOT private US companies, which register at the state level'). This gives an agent clear routing criteria relative to other tools.

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