search_companies

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

With no annotations provided, the description carries full burden. It discloses key behaviors: requires Apollo Basic plan (returns 403 on free tier), does not consume credits, and does not return email addresses. This is sufficient for an AI agent to understand side effects and constraints, though it could mention pagination or rate limits.

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 concise with two paragraph-like sections: purpose then prerequisites/caveats. It front-loads the main action and uses line breaks for readability. Every sentence adds information, though the plan requirement could be integrated more seamlessly.

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 no output schema, the description does not explain the structure of results (e.g., company objects, pagination meta). It covers prerequisites, non-consumption of credits, and what not to expect, but lacks details on return format or how to navigate results. This is a notable gap for an AI agent deciding whether to use this tool.

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 baseline is 3. The description summarizes parameters as 'keyword, location, or headcount' but does not add deeper semantics beyond what the schema provides. The schema already describes each parameter with examples and ranges, so the description adds minimal value here.

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 searches Apollo's company database by keyword, location, or headcount. It uses specific verbs and resources, and distinguishes itself from sibling tools like enrich_company and hunter_find_emails_by_domain by noting what it does not do (return emails) and what alternatives exist.

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?

Explicitly states when to use this tool vs alternatives: 'Does NOT return email addresses. To get contacts from results, use hunter_find_emails_by_domain (Hunter) or enrich_company (Apollo) for firmographic details.' Also notes the prerequisite of an Apollo Basic plan, which helps the agent avoid 403 errors.

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