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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, establishing a safe read-only profile. The description adds valuable behavior beyond annotations: default TXT filtering, honest pre-filter count, next_calls chain logic, conditional emission of ssl_check/tech_fingerprint, and rate limits. No contradiction.

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?

Description is well-structured and front-loaded with the core purpose. Each of the five sentences serves a distinct role: purpose, filtering semantics, usage alternative, next_calls guidance, and return summary. No wasted words for a tool with this complexity.

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 tool's complexity and the presence of an output schema, the description covers all necessary context: return categories (DNS, WHOIS, SSL, risk score, etc.), next_calls chaining, default filtering behavior, and rate limits. It is complete for an agent to select and invoke the tool without additional clues.

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 both parameters are richly documented in the input schema (e.g., include_all_txt's default filter, total_txt_records behavior, and vendor-verification stripping). The tool description largely restates these same details without adding new meaning beyond the schema, so baseline 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 clearly states the tool's function: 'Query DNS, WHOIS, SSL, subdomains, and threat intel for a domain in one call.' It distinguishes itself from siblings by positioning as an all-in-one starting point and explicitly contrasts with audit_domain for live headers and tech stack.

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?

Provides explicit usage context: 'Use as a starting point for domain investigations; use audit_domain for live headers + tech stack.' Also explains when to set include_all_txt=true and how to chain next_calls with subdomain_enum, ssl_check, and tech_fingerprint. This is concrete when-to-use vs. alternative guidance.

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