search_rdap

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

With no annotations, the description carries the full burden and does useful work: it discloses that registrant contacts are redacted by policy, that no API key is required, and (via '[passive]' plus the query-source note) that it contacts IANA/the registry rather than the target. It omits rate limits and failure behavior, so not a 5.

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?

Front-loaded with the core purpose and returned fields, then terse supporting notes about redaction, auth, and reach. Dense but every sentence carries information; the prose could be slightly tightened but nothing is 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?

For a read-only lookup with no output schema and no annotations, the description supplies the important gaps: what fields come back, that contacts are redacted, that no key is needed, and the passive lookup source. Only the 'domain' parameter's format and any return-shape nuance are left unaddressed.

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 only 50% – 'domain' is undocumented in the schema and the description never explains its expected format (bare domain vs. URL, TLD handling). 'json_output' is covered by the schema, so the description adds little beyond the baseline.

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?

States a specific verb+resource ('Structured domain registration lookup via RDAP') and enumerates the returned fields (registrar, dates, name servers, status codes). It contrasts itself with WHOIS ('machine-readable successor'), which implicitly distinguishes it from the sibling search_whois, though it never names that tool directly.

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?

Usage is only implied: by framing RDAP as the machine-readable successor to WHOIS, the description hints it is the preferred structured alternative, but it gives no explicit when-to-use/when-not guidance and never names search_whois as the alternative.

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