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

Annotations already provide key behavioral information (readOnlyHint=true, destructiveHint=false, idempotentHint=true, openWorldHint=true). The description adds minimal behavioral insight beyond listing returned data. It does not disclose rate limits, data freshness, or potential limitations.

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 two sentences, efficient but somewhat list-like. It front-loads the main purpose and key data points. Could be slightly more structured (e.g., separating company data vs. email data) but is not overly verbose.

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 rich output schema (not shown but implied), the description provides adequate context. It mentions 50M+ domains indexed, giving a sense of coverage. It lacks details on pagination, rate limits, or data update frequency, but for a tool of this complexity, the description is sufficiently complete.

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% with clear parameter descriptions. The tool description does not add significant new information about the parameters beyond what the schema already provides. It mentions email confidence scores but does not elaborate on how they are calculated or their meaning.

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 states the tool finds professional email addresses and company data for any domain, listing specific data points (organization name, industry, employee count, tech stack, social profiles, email pattern, verified contact emails with confidence scores, positions, departments, seniority levels). The name and title ('business.hunter.company', 'Company Email & Enrichment by Domain') reinforce the purpose.

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 explains what the tool does but does not provide guidance on when to use it versus sibling tools like email validation or other business lookups. No explicit when-to-use, when-not-to-use, or alternative tools are mentioned.

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