capabilities

WHOIS lookup for a domain, from the registry RDAP record

domain_registration

Read-onlyIdempotent

The WHOIS lookup for a domain, answered from the registry's own RDAP service - the structured successor to port-43 WHOIS, read live via the IANA bootstrap, never scraped WHOIS text. Use when: Answer a WHOIS question about a domain - registrar, creation date, expiry, transfer lock - from the registry record. Not for: You only need the expiry date and days remaining - use domain.expiry (cheaper). Related: domain_expiry. Price: USD 0.004/call (x402), 0.003 (account key).

Input Schema

TableJSON Schema

Name	Required	Description	Default
`domain`	Yes	Bare domain name such as example.com or bbc.co.uk. Internationalised names are converted to punycode (IDNA). URLs, paths, ports and single-label names are rejected.

Output Schema

TableJSON Schema

Name	Required	Description	Default
`data`	Yes	Capability output; full JSON Schema at https://api.eckari.com/v1/capabilities/domain.registration
`meta`	Yes

TDQS

A4.4/5.0

Behavior4/5

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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint (false). The description adds valuable context: the data is retrieved live via the IANA bootstrap (not scraped WHOIS text), and the pricing is disclosed ($0.004/call). This goes beyond the annotations, though it does not detail failure modes or latency which would be needed for a perfect score.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is well-structured with a clear opening sentence, followed by 'Use when' and 'Not for' sections, and a pricing note. It is front-loaded with the essential purpose. The pricing information, while helpful, adds slight length but does not detract from readability. Nearly every sentence earns its place, earning a high score.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the low complexity (single parameter, clear annotations, output schema present), the description is fully complete. It covers purpose, usage guidelines, data source, pricing, and alternatives. The agent has all necessary context to decide whether to invoke this tool, and the output schema handles return values without needing description.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

With only one parameter and 100% schema description coverage, the input schema already provides rich semantics (pattern, length limits, punycode conversion, URL/port rejection). The tool description does not add further meaning about the parameter beyond restating its purpose. Baseline of 3 is appropriate given the schema carries the load.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool performs WHOIS lookup via RDAP, specifying it returns registrar, creation date, expiry, transfer lock. It distinguishes itself from the sibling domain_expiry by noting that tool is cheaper and limited to expiry dates. The verb 'lookup' and resource 'domain' are specific, and the data source (registry RDAP) is explicit.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides explicit 'Use when' and 'Not for' conditions, directly referencing the sibling tool domain_expiry as a cheaper alternative for expiry-only queries. It also lists concrete use cases (registrar, creation date, expiry, transfer lock), giving clear guidance on when to invoke this tool versus alternatives.

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

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TDQS

A4.4/5.0

Disambiguation4/5

Tools are largely distinct, targeting specific entities (UK company, US company, domain, LEI, FX, location, parcel, weather) or sub-aspects (e.g., accounts vs. charges vs. directors). Overlap exists between company.uk.profile and company.uk.status (both contain status info, but the latter is cheaper and focused). Also, company.uk.filings and company.us.filings_latest could be confused if an agent generalizes 'filings' across jurisdictions.

Naming Consistency5/5

All tools follow a consistent pattern: domain_entity_subject (e.g., company_uk_accounts, domain_expiry, weather_us_alerts). Underscores and lower case are used throughout. Verbs are implied by the noun (e.g., 'search' for lookup, 'detect' for identification). No mixed conventions or unpredictable names.

Tool Count4/5

24 tools is on the high side but still reasonable for a general-purpose data server spanning multiple domains (company, domain, entity, fx, location, parcel, weather). Each domain gets a cohesive set, and the documentation justifies each tool. Could be slightly leaner if some niche tools (e.g., domain_expiry vs. registration) were merged, but overall scoping is acceptable.

Completeness4/5

Each domain offers good coverage: UK company tools cover CRUD-like operations (profile, status, search, filings, charges, directors, owners, registered office); similarly for US companies (profile, filings, resolve, latest filings). Weather has forecast, observation, alerts. Parcel only detects carrier (no tracking). Missing features like advanced filtering on company filings or less common domains, but core workflows are covered.

Resources

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