Domain Sentinel

Domain Sentinel provides domain verification and monitoring tools built on the RDAP protocol. It offers fast lookups, watchlists, email alerts for availability, expiry, and WHOIS changes, as well as DNS and TLS certificate monitoring. Users can manage domains via a remote MCP server integrated with AI assistants, and access pricing plans ranging from free to paid tiers.

Domain Sentinel publishes 1 API contract indexed on the APIs.io network: Lookup API. Tagged areas include Domain Monitoring, WHOIS Lookup, RDAP API, Brand Protection, and Expiry Alerts.

The Domain Sentinel catalog on APIs.io includes 1 JSON-LD context and 1 Spectral governance ruleset.

Domain Sentinel’s developer surface includes authentication, documentation, API reference, getting-started guide, pricing, engineering blog, signup flow, and 15 more developer resources.

🌐 Visit website 📡 Profile data on GitHub

48.2/100 developing Agent 36/100 agent ready Full breakdown ↓
scored 2026-11-06 · rubric v0.27.0 · Show this score on your site →

AccessFreemiumSelf serve⚡ Free to try

1 published contract

Domain MonitoringWHOIS LookupRDAP APIBrand ProtectionExpiry AlertsDNS Monitoring

Kin Score

Kin Score How this is scored →
scored 2026-11-06 · rubric v0.27.0

Composite quality — 48.2/100 · developing

Contract Quality 13.4 / 21

Developer Ergonomics 7.3 / 17

Access Clarity 11.2 / 17

Operational Transparency 0.0 / 11

Contract Governance 2.2 / 10

Discoverability 5.6 / 9

Regulatory Posture 3.7 / 15

Agent readiness — 36/100 · agent ready

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 0 / 6

MCP Server 0 / 12

Machine-Readable Auth 10 / 10

Idempotency 0 / 9

Stable Error Semantics 8 / 8

Request/Response Examples 7 / 7

Rate-Limit Signaling 0 / 7

Typed Event Surface 0 / 6

Agent Skills 0 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 0 / 4

Delegated User Identity 6 / 6

Protected Resource Metadata 0 / 5

Registration Without a Human 6 / 6

Agentic Commerce Well-Known Document 0 / 5

Pagination 5 / 5

Distinct Operations 3 / 3

MCP Tool Quality 6 / 6

Regulatory Posture applies to this provider. Its tags matched the Horizontal (data, software, accessibility, platform) regime, so Regulatory Posture carries 15 points of the composite. If this regime is wrong for your business, say so on your provider repo — the applicability map is public and we will correct it.

Create-or-Update Ergonomics could not be measured. We hold no machine-readable contract for this provider to read, so there is nothing to measure a write surface against. Excluded rather than scored zero: never-measured and measured-empty are different facts. Publishing an OpenAPI is what makes this facet — and several others — scorable at all.

The six quality facets above are damped to 85 points between them, because the conditional facet above carries the other 15. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 85% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.

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Agent readiness — checks not met, largest first (exact, from this profile):

MCP Server +12 pts — deployment.mode + probe verdict on the mcp/ manifest, not the pointer; an unprobed slug falls back to authorship
Idempotency +9 pts — OpenAPI mutating operations declare an idempotency key — a header, a request-body property, or a named de-duplication token whose own description says so (verified); else common[].type matches /idempoten/i (documented)
A2A Agent Card +8 pts — a2a/-a2a.yml manifest, graded on conformance.grade against A2A 1.0.0
Rate-Limit Signaling +7 pts — OpenAPI responses document X-RateLimit-* / RateLimit headers (verified), else a rate_limits artifact or RateLimits link (documented)
Typed Event Surface +6 pts — AsyncAPI document, OR webhooks/callbacks objects in the as-published OpenAPI, OR common[].type includes Webhooks
Documented Reversibility +6 pts — a reversal operation in the contract, graded up when a window is documented too

6 more unmet checks in the Agent Readiness table above.

Kin Score — facets with the most composite points still available (weight × headroom):

Operational Transparency scores 0.0 — up to +13.0 composite points
Developer Ergonomics scores 42.9 — up to +11.4 composite points
Contract Governance scores 22.0 — up to +9.4 composite points

Each check links to what satisfies it. Publish the artifact, or tell us where it already lives, and the score moves on the next scoring run.

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. Every facet and dimension name above is a link: it opens that measurement's own page — what it means, the exact checks that feed it, how the whole catalog distributes on it, and the providers at the top of it. This rating is computed from the provider profile at artifacts.apis.io/domain-sentinel-com/apis.yml: open an issue on github.com/api-evangelist/domain-sentinel-com to ask a question or point us at an artifact you publish. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

Standards implemented 2

Standards this provider implements or carries. De facto ones are profiled and measured by the API Commons; formal ones come from the standards directory and are linked by the provider's own tags. The evidence column says how each claim was established — not that it was made.

Dynamic Client Registration

measured — observed by APIs.io (published)

OpenAPI

measured — observed by APIs.io (published)

APIs 1

Individual APIs this provider publishes, each with its own machine-readable definition.

Domain Sentinel Lookup API

The Lookup API from Domain Sentinel — 1 operation(s) for lookup.

Domain Sentinel API pricing

Prices published by Domain Sentinel, read 2026-11-05 from www.domain-sentinel.com/en/pricing.

Plan	Price
Free	0 € forever
Pro	9 € per month, excl. VAT or 79 € a year, excl. VAT

Plan details, limits and sources →

Pricing Plans 1

Published pricing tiers and plan structures.

Domain Sentinel Com Plans Pricing

2 plans

PLANS

Semantic Vocabularies 1

JSON-LD contexts and semantic vocabularies used across these APIs.

Domain Sentinel Com Context

5 classes · 33 properties

JSON-LD

Spectral Rules 1

Spectral governance rulesets for linting and validating these APIs.

Domain Sentinel API Rules

43 rules · 41 errors 1 warnings 1 info

SPECTRAL

JSON Schema 1

Standalone JSON Schema definitions for this provider's data models.

DomainLookup

17 properties

JSON SCHEMA

Security Posture 2

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Domain Sentinel Com Authentication

http · 1 scheme

SECURITY

Domain Sentinel Com Domain Security

TLSv1.3 · HSTS · DNSSEC · DMARC

SECURITY

Agentic Access 1

Recommended x-agentic-access execution contracts for AI agents.

Domain Sentinel Com Agentic Access

1 operation

1 operations · 0 acting

AGENTIC

Resources

Get Started 2

Portal, sign-up, and the first successful call

GettingStarted

GettingStarted

SignUp

SignUp

Documentation 2

Reference material describing how the API behaves

Documentation

Documentation

APIReference

APIReference

Agent Surfaces 3

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess

AgenticAccess

LLMsTxt

LLMsTxt

WellKnown

WellKnown

Design & Contract 6

Pagination, idempotency, versioning, errors, and events

Spectral

JSONLD

Vocabulary

DataModel

ErrorCatalog

Conformance

Access & Security 2

Authentication, authorization, and security posture

Authentication

Authentication

DomainSecurity

DomainSecurity

Commercial 4

Pricing, plans, and the legal terms of use

Plans

Pricing

TermsOfService

PrivacyPolicy

Company 2

The organization behind the API

Website

Website

Blog

Blog

Other 1

Properties that don't map to a standard resource type

Hosts

Hosts

Source (apis.yml)

aid: domain-sentinel-com
name: Domain Sentinel
accessModel:
  pricing: freemium
  onboarding: self-serve
  trial: false
  try_now: true
  public: false
  gated: none
  gated_source:
  - onboarding
  label: Freemium · Self-serve signup
  confidence: medium
  probe_state: gated
  source:
  - plans
  - authentication
  - security
  generated: '2026-11-06'
  method: derived
image: https://www.domain-sentinel.com/en/opengraph-image?16020a51503cda55
description: Domain Sentinel provides domain verification and monitoring tools built on the RDAP protocol. It offers fast
  lookups, watchlists, email alerts for availability, expiry, and WHOIS changes, as well as DNS and TLS certificate monitoring.
  Users can manage domains via a remote MCP server integrated with AI assistants, and access pricing plans ranging from free
  to paid tiers.
url: https://artifacts.apis.io/domain-sentinel-com/apis.yml
x-type: company
x-source: harvest:mcp-registry
x-tier: profiled
x-tier-reason: enrichment pass 2026-11-05 (modular-v1; was harvest)
specificationVersion: '0.20'
created: '2026-11-05'
modified: '2026-11-05'
tags:
- Domain Monitoring
- WHOIS Lookup
- RDAP API
- Brand Protection
- Expiry Alerts
- DNS Monitoring
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: AgenticAccess
  url: agentic-access/domain-sentinel-com-agentic-access.yml
- type: Plans
  url: plans/domain-sentinel-com-plans-pricing.yml
- type: Spectral
  url: rules/domain-sentinel-com-rules.yml
- type: JSONLD
  url: json-ld/domain-sentinel-com-context.jsonld
- type: Vocabulary
  url: vocabulary/domain-sentinel-com-vocabulary.yml
- type: DataModel
  url: data-model/domain-sentinel-com-data-model.yml
- type: ErrorCatalog
  url: errors/domain-sentinel-com-problem-types.yml
- type: Conformance
  url: conformance/domain-sentinel-com-conformance.yml
- type: LLMsTxt
  url: llms/domain-sentinel-com-llms.txt
- type: WellKnown
  url: well-known/domain-sentinel-com-well-known.yml
- type: Hosts
  url: hosts/domain-sentinel-com-hosts.yml
- type: Authentication
  url: authentication/domain-sentinel-com-authentication.yml
- type: DomainSecurity
  url: security/domain-sentinel-com-domain-security.yml
- type: Website
  url: https://domain-sentinel.com/
- type: Documentation
  url: https://www.domain-sentinel.com/en/docs
- type: APIReference
  url: https://www.domain-sentinel.com/en/docs
- type: GettingStarted
  url: https://www.domain-sentinel.com/en/docs
- type: Pricing
  url: https://www.domain-sentinel.com/en/pricing
- type: Blog
  url: https://www.domain-sentinel.com/en/blog
- type: SignUp
  url: https://www.domain-sentinel.com/en/register
- type: TermsOfService
  url: https://www.domain-sentinel.com/en/terms
- type: PrivacyPolicy
  url: https://www.domain-sentinel.com/en/privacy
apis:
- aid: domain-sentinel-com:domain-sentinel-com-lookup-api
  name: Domain Sentinel Lookup API
  description: The Lookup API from Domain Sentinel — 1 operation(s) for lookup.
  humanURL: https://www.domain-sentinel.com/en/docs
  baseURL: https://api.domain-sentinel.com
  tags:
  - Lookup
  properties:
  - type: OpenAPI
    url: openapi/domain-sentinel-com-lookup-api-openapi.yml
  - type: JSONSchema
    url: json-schema/domain-sentinel-com-domain-lookup-schema.json
x-coverage:
  state: gated
  reason: partner-login
  method: derived
  generated: '2026-11-05'
  generator: derive-coverage.py (pre-flight evidence)
  detail: the company serves an API surface but requires credentials before any description of it can be read
  evidence:
  - url: https://api.domain-sentinel.com/v1/openapi.json
    status: null
  - url: https://api.domain-sentinel.com/mcp
    status: 401
  - url: https://domain-sentinel.com/
    status: 200
x-enrichment:
  date: '2026-11-05'
  status: enriched
  artifacts_added: 23
  pass: modular-v1
  engine: identity=local,contract=local,surfaces=local,docs=local,regulatory=local

Domain Sentinel API — frequently asked questions

Does Domain Sentinel have an API?

Yes. APIs.io lists 1 API from Domain Sentinel, including Domain Sentinel Lookup API.

Is there an OpenAPI specification for the Domain Sentinel API?

Yes. APIs.io indexes 1 OpenAPI specification for Domain Sentinel, each linked for download from this page.

How do I authenticate with the Domain Sentinel API?

Domain Sentinel documents its authentication (http · 1 scheme). The details are profiled on APIs.io as Domain Sentinel Com Authentication.

How much does the Domain Sentinel API cost?

Domain Sentinel publishes its prices; its Free plan is 0 € forever as of 2026-11-05. APIs.io lists 2 pricing plans for Domain Sentinel, with each plan's price, limits and inclusions under Pricing on this page.

Is the Domain Sentinel API ready for AI agents?

Domain Sentinel has a Kin Score of 48.2 out of 100 (developing) and an Agent Readiness score of 35.6 (agent-ready), scored by API Evangelist on 2026-11-06.

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