Extract Contacts ($0.01)

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

No annotations are provided, so the description carries full burden. It discloses a monetary cost ($0.01 USDC on Base), which is a key behavioral trait. However, it does not mention rate limits, authentication requirements, or output format, leaving gaps in 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?

Two sentences concisely convey purpose and cost. Every word is necessary, and the description is front-loaded with the action and outputs, then the cost. No unnecessary details.

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?

The tool is simple (one param, no output schema), and the description covers core purpose and cost. However, it omits details like whether extraction handles dynamic content, required permissions, or return structure. Given the low complexity, it is mostly complete but has minor gaps.

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 sole parameter (url) is described in the schema as 'Website URL.' The description adds no additional semantics beyond the schema, and with 100% schema coverage, the baseline is 3. The description does not enhance understanding of the parameter beyond its basic type.

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 extracts emails, phone numbers, and social links from any website for lead enrichment. It uses a specific verb (extract) and resource (contacts), and the purpose is well-defined, distinguishing it from sibling tools like extract_text and page_metadata.

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 implies use for lead enrichment and prospecting but provides no explicit when-to-use or when-not-to-use guidance. It does not differentiate from similar siblings like extract_text or site_audit, leaving the agent to infer context.

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