CustomerOS

CustomerOS (formerly Openline) is a London-based revenue-intelligence platform for B2B go-to-market teams. It identifies anonymous website visitors, scores them against an ideal customer profile, infers buying stage from page engagement, and attributes content and ad spend to real pipeline. The developer surface spans a first-party JavaScript website tracker installed behind a customer-owned reverse-proxy CNAME, a set of key-authenticated REST APIs published as OpenAPI in the company monorepo (CustomerBASE contacts and organizations, person and organization enrichment, email verification and IP intelligence, Mailstack sending domains and mailboxes, billing invoices, outreach tracking), a 34-operation Flow API for outbound sequencing, and the open-source customer-os-api GraphQL server that predates the pivot. CustomerOS also runs a live anonymous MCP server and serves an A2A agent card from its documentation host.

CustomerOS publishes 10 APIs on the APIs.io network, including GraphQL API, Billing API, CustomerBASE API, and 7 more. Tagged areas include CRM, Revenue, Go-To-Market, Lead Intelligence, and Visitor Identification.

CustomerOS’s developer surface includes documentation, getting-started guide, engineering blog, pricing, changelog, authentication, and 37 more developer resources.

🌐 Visit website 📡 Source on GitHub

52.4/100 developing ▬ flat Agent 32/100 agent ready Full breakdown ↓
scored 2026-09-08 · rubric v0.20.0

AccessPaid

10 APIs 1 MCP Servers

CRM Revenue Go-To-Market Lead Intelligence Visitor Identification Attribution Email Verification Enrichment GraphQL Open-Source

Kin Score

Kin Score How this is scored →
scored 2026-09-08 · rubric v0.20.0

Composite quality — 52.4/100 · developing

Contract Quality 11.7 / 23

Developer Ergonomics 6.8 / 18

Access Clarity 14.9 / 18

Operational Transparency 3.1 / 12

Contract Governance 0.5 / 11

Discoverability 7.3 / 9

Create-or-Update Ergonomics 3.9 / 10

Agent readiness — 32/100 · agent ready

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 0 / 6

MCP Server 12 / 12

Machine-Readable Auth 10 / 10

Idempotency 0 / 9

Stable Error Semantics 8 / 8

Request/Response Examples 7 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 0 / 6

Agent Skills 5 / 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 0 / 6

Protected Resource Metadata 0 / 5

Registration Without a Human 0 / 6

Agentic Commerce Well-Known Document 0 / 5

Create-or-Update Ergonomics applies to this provider. This API accepts writes, so it carries 10 points of the composite. It is scored from the published contracts themselves: whether a caller can create-or-update in one call, whether the write accepts a key the caller already holds, and whether the response says which branch ran. Without that, every write needs a search-and-branch in front of it, and the first time that check is skipped a duplicate record is created. Scored against the observed mean rather than raw — a provider at the catalog average is unchanged by this facet, not penalised by it.

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 github.com/api-evangelist/customeros: open an issue to ask a question, or submit a pull request to add artifacts. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

APIs 11

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

CustomerOS Website Tracker

Client-side JavaScript tracker that captures page views and custom events, exposes window.cos.identify() for attaching identity and properties, and matches visitor IPs to compan...

CustomerOS GraphQL API

Single GraphQL endpoint served by the open-source customer-os-api (Go, gqlgen) covering organizations, contacts, opportunities, contracts, invoices, interactions and timeline ev...

CustomerOS Billing API

The Billing API API from CustomerOS — 1 operation(s) for billing api.

CustomerOS CustomerBASE API

The CustomerBASE API API from CustomerOS — 6 operation(s) for customerbase api.

CustomerOS Domains API

The Domains API from CustomerOS — 2 operation(s) for domains.

CustomerOS Email Verification API

The Email Verification API from CustomerOS — 4 operation(s) for email verification.

CustomerOS Enrichment API

The Enrichment API API from CustomerOS — 3 operation(s) for enrichment api.

CustomerOS Flows API

The Flows API from CustomerOS — 18 operation(s) for flows.

CustomerOS IP Intelligence API

The IP Intelligence API from CustomerOS — 1 operation(s) for ip intelligence.

CustomerOS Mailboxes API

The Mailboxes API from CustomerOS — 1 operation(s) for mailboxes.

CustomerOS Outreach API

The Outreach API from CustomerOS — 1 operation(s) for outreach.

Scroll for all 11

Open Collections 10

Open, tool-agnostic API collections (OpenAPI-derived and Bruno).

API Collection

OPEN COLLECTION

CustomerOS API

OPEN COLLECTION

CustomerOS API

OPEN COLLECTION

CustomerOS API

OPEN COLLECTION

CustomerOS API

OPEN COLLECTION

CustomerOS API

OPEN COLLECTION

CustomerOS GraphQL API

OPEN COLLECTION

CustomerOS API

OPEN COLLECTION

CustomerOS API

OPEN COLLECTION

CustomerOS GraphQL API

OPEN COLLECTION

Scroll for all 10

MCP Servers 1

Model Context Protocol servers that expose these APIs to AI agents.

CustomerOS MCP Server

CustomerOS runs a live, anonymous, remote MCP server on its documentation host. It is a DOCUMENTATION server (search + a read-only virtual filesystem over the docs pages and the...

MCP SERVER

GraphQL 1

GraphQL schemas published by this provider.

CustomerOS GraphQL Schema

Representative GraphQL schema for the [CustomerOS](https://customeros.ai/) (formerly Openline)

GRAPHQL

Pricing Plans 1

Published pricing tiers and plan structures.

Customeros Plans Pricing

2 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Customeros Rate Limits

0 limits

RATE LIMITS

FinOps 1

Cost, billing, and metering signals for API financial operations.

Customeros Finops

FINOPS

Security Posture 3

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

Customeros Authentication

apiKey · 2 schemes

SECURITY

Customeros Domain Security

TLSv1.3 · HSTS · DNSSEC · DMARC

SECURITY

Customeros Trust Center

CASA Type 2

SECURITY

Agentic Access 1

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

Customeros Agentic Access

57 operations · 30 acting · 1 human-in-the-loop

57 operations · 30 acting

AGENTIC

Resources

Get Started 2

Portal, sign-up, and the first successful call

GettingStarted

GettingStarted

Login

Documentation 1

Reference material describing how the API behaves

Documentation

Documentation

Agent Surfaces 5

MCP servers, agent skills, and machine-readable catalogs

MCPServer

AgentSkill

LLMsTxt

WellKnown

AgenticAccess

Design & Contract 6

Pagination, idempotency, versioning, errors, and events

Conventions

ErrorCatalog

Lifecycle

Conformance

DataModel

Components

Build 3

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

GitHubOrganization

ToolCrosswalk

ToolCrosswalk

Packages

Packages

Access & Security 4

Authentication, authorization, and security posture

Compliance

Authentication

TrustCenter

DomainSecurity

Operate 4

Status, limits, changes, and where to get help

StatusPage

ChangeLog

ChangeLog

RateLimits

Commercial 5

Pricing, plans, and the legal terms of use

Pricing

TermsOfService

PrivacyPolicy

Plans

FinOps

Company 3

The organization behind the API

Website

Website

Blog

Blog

LinkedIn

Other 10

Properties that don't map to a standard resource type

AgentCard

Protobuf

Overlay

Overlay

Overlay

Overlay

Overlay

Overlay

Overlay

Overlay

Scroll for all 10

Source (apis.yml)

aid: customeros
url: https://raw.githubusercontent.com/api-evangelist/customeros/refs/heads/main/apis.yml
name: CustomerOS
kind: company
description: CustomerOS (formerly Openline) is a London-based revenue-intelligence platform for B2B go-to-market teams. It
  identifies anonymous website visitors, scores them against an ideal customer profile, infers buying stage from page engagement,
  and attributes content and ad spend to real pipeline. The developer surface spans a first-party JavaScript website tracker
  installed behind a customer-owned reverse-proxy CNAME, a set of key-authenticated REST APIs published as OpenAPI in the
  company monorepo (CustomerBASE contacts and organizations, person and organization enrichment, email verification and IP
  intelligence, Mailstack sending domains and mailboxes, billing invoices, outreach tracking), a 34-operation Flow API for
  outbound sequencing, and the open-source customer-os-api GraphQL server that predates the pivot. CustomerOS also runs a
  live anonymous MCP server and serves an A2A agent card from its documentation host.
deliveryModel:
  model: unknown
  open_source: unknown
  commercial: true
  callable_host: false
  label: Delivery model not determined — needs a product licence on record
  confidence: low
  source:
  - openapi
  - pricing
  - repository-unlicensed
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: paid
  onboarding: sales-assisted
  trial: false
  try_now: false
  public: false
  label: Paid · Sales-assisted onboarding · API access granted on request
  confidence: high
  source:
  - plans
  - authentication
  generated: '2026-08-13'
  method: searched
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/customeros.png
tags:
- CRM
- Revenue
- Go-To-Market
- Lead Intelligence
- Visitor Identification
- Attribution
- Email Verification
- Enrichment
- GraphQL
- Open-Source
tags_raw:
- CRM
- Revenue
- Go-To-Market
- Lead Intelligence
- Visitor Identification
- Attribution
- Email Verification
- Enrichment
- GraphQL
- Open Source
created: '2026-06-20'
modified: '2026-08-13'
specificationVersion: '0.23'
apis:
- aid: customeros:customeros-website-tracker
  name: CustomerOS Website Tracker
  tags:
  - Tracking
  - Visitor Identification
  - JavaScript
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  humanURL: https://docs.customeros.ai/website-tracker
  baseURL: https://{customer-reverse-proxy-domain}/analytics-0.1.js
  properties:
  - url: https://docs.customeros.ai/website-tracker
    type: Documentation
  - url: https://docs.customeros.ai/tracker/custom-events
    type: Documentation
    name: Custom events (Alpha)
  - url: components/customeros-components.yml
    type: Components
  description: Client-side JavaScript tracker that captures page views and custom events, exposes window.cos.identify() for
    attaching identity and properties, and matches visitor IPs to companies. Since the 2025-09-08 change CustomerOS supports
    it ONLY when served from a reverse proxy on the customer's own domain, so the base URL is templated by design — there
    is no CustomerOS-hosted CDN URL to record and no version-pinned build.
- aid: customeros:customeros-graphql-api
  name: CustomerOS GraphQL API
  description: 'Single GraphQL endpoint served by the open-source customer-os-api (Go, gqlgen) covering organizations, contacts,
    opportunities, contracts, invoices, interactions and timeline events. The repository moved with the rename: github.com/openline-ai/openline-customer-os
    now 301s to github.com/customeros/customeros, where 69 .graphqls schema files are published. Introspection could not be
    run — the published endpoint host does not resolve.'
  humanURL: https://github.com/customeros/customeros
  baseURL: https://api.customeros.ai/query
  tags:
  - GraphQL
  properties:
  - type: OpenAPI
    url: openapi/customeros-graphql-api-openapi.yml
    name: HTTP envelope for POST /query
  - type: GraphQL
    url: graphql/customeros-graphql.md
  - type: GraphQL
    url: graphql/customeros-schema.graphql
    name: Representative schema
  - type: SourceCode
    url: https://github.com/customeros/customeros
  - type: Documentation
    url: https://docs.customeros.ai/data-structure
  - type: Documentation
    url: https://docs.customeros.ai/contacts
- aid: customeros:customeros-billing-api-api
  name: CustomerOS Billing API
  description: The Billing API API from CustomerOS — 1 operation(s) for billing api.
  humanURL: https://github.com/customeros/customeros/tree/otter/packages/server/customer-os-api/docs
  baseURL: https://api.customeros.ai
  tags:
  - Billing API
  properties:
  - type: OpenAPI
    url: openapi/customeros-billing-api-api-openapi.yml
  - type: Swagger
    url: openapi/_original/customeros-swagger.json
  - type: SourceCode
    url: https://github.com/customeros/customeros
  - type: Documentation
    url: https://docs.customeros.ai
- aid: customeros:customeros-customerbase-api-api
  name: CustomerOS CustomerBASE API
  description: The CustomerBASE API API from CustomerOS — 6 operation(s) for customerbase api.
  humanURL: https://github.com/customeros/customeros/tree/otter/packages/server/customer-os-api/docs
  baseURL: https://api.customeros.ai
  tags:
  - CustomerBASE API
  properties:
  - type: OpenAPI
    url: openapi/customeros-customerbase-api-api-openapi.yml
  - type: Swagger
    url: openapi/_original/customeros-swagger.json
  - type: SourceCode
    url: https://github.com/customeros/customeros
  - type: Documentation
    url: https://docs.customeros.ai
- aid: customeros:customeros-domains-api
  name: CustomerOS Domains API
  description: The Domains API from CustomerOS — 2 operation(s) for domains.
  humanURL: https://github.com/customeros/customeros/tree/otter/packages/server/customer-os-api/docs
  baseURL: https://api.customeros.ai
  tags:
  - Domains
  properties:
  - type: OpenAPI
    url: openapi/customeros-domains-api-openapi.yml
  - type: Swagger
    url: openapi/_original/customeros-swagger.json
  - type: SourceCode
    url: https://github.com/customeros/customeros
  - type: Documentation
    url: https://docs.customeros.ai
- aid: customeros:customeros-email-verification-api
  name: CustomerOS Email Verification API
  description: The Email Verification API from CustomerOS — 4 operation(s) for email verification.
  humanURL: https://github.com/customeros/customeros/tree/otter/packages/server/customer-os-api/docs
  baseURL: https://api.customeros.ai
  tags:
  - Email Verification
  properties:
  - type: OpenAPI
    url: openapi/customeros-email-verification-api-openapi.yml
  - type: Swagger
    url: openapi/_original/customeros-swagger.json
  - type: SourceCode
    url: https://github.com/customeros/customeros
  - type: Documentation
    url: https://docs.customeros.ai
- aid: customeros:customeros-enrichment-api-api
  name: CustomerOS Enrichment API
  description: The Enrichment API API from CustomerOS — 3 operation(s) for enrichment api.
  humanURL: https://github.com/customeros/customeros/tree/otter/packages/server/customer-os-api/docs
  baseURL: https://api.customeros.ai
  tags:
  - Enrichment API
  properties:
  - type: OpenAPI
    url: openapi/customeros-enrichment-api-api-openapi.yml
  - type: Swagger
    url: openapi/_original/customeros-swagger.json
  - type: SourceCode
    url: https://github.com/customeros/customeros
  - type: Documentation
    url: https://docs.customeros.ai
- aid: customeros:customeros-flows-api
  name: CustomerOS Flows API
  description: The Flows API from CustomerOS — 18 operation(s) for flows.
  humanURL: https://github.com/customeros/customeros/tree/otter/packages/server/customer-os-api/docs
  baseURL: https://api.customeros.ai
  tags:
  - Flows
  properties:
  - type: OpenAPI
    url: openapi/customeros-flows-api-openapi.yml
  - type: Swagger
    url: openapi/_original/customeros-swagger.json
  - type: SourceCode
    url: https://github.com/customeros/customeros
  - type: Documentation
    url: https://docs.customeros.ai
- aid: customeros:customeros-ip-intelligence-api
  name: CustomerOS IP Intelligence API
  description: The IP Intelligence API from CustomerOS — 1 operation(s) for ip intelligence.
  humanURL: https://github.com/customeros/customeros/tree/otter/packages/server/customer-os-api/docs
  baseURL: https://api.customeros.ai
  tags:
  - IP Intelligence
  properties:
  - type: OpenAPI
    url: openapi/customeros-ip-intelligence-api-openapi.yml
  - type: Swagger
    url: openapi/_original/customeros-swagger.json
  - type: SourceCode
    url: https://github.com/customeros/customeros
  - type: Documentation
    url: https://docs.customeros.ai
- aid: customeros:customeros-mailboxes-api
  name: CustomerOS Mailboxes API
  description: The Mailboxes API from CustomerOS — 1 operation(s) for mailboxes.
  humanURL: https://github.com/customeros/customeros/tree/otter/packages/server/customer-os-api/docs
  baseURL: https://api.customeros.ai
  tags:
  - Mailboxes
  properties:
  - type: OpenAPI
    url: openapi/customeros-mailboxes-api-openapi.yml
  - type: Swagger
    url: openapi/_original/customeros-swagger.json
  - type: SourceCode
    url: https://github.com/customeros/customeros
  - type: Documentation
    url: https://docs.customeros.ai
- aid: customeros:customeros-outreach-api
  name: CustomerOS Outreach API
  description: The Outreach API from CustomerOS — 1 operation(s) for outreach.
  humanURL: https://github.com/customeros/customeros/tree/otter/packages/server/customer-os-api/docs
  baseURL: https://api.customeros.ai
  tags:
  - Outreach
  properties:
  - type: OpenAPI
    url: openapi/customeros-outreach-api-openapi.yml
  - type: Swagger
    url: openapi/_original/customeros-swagger.json
  - type: SourceCode
    url: https://github.com/customeros/customeros
  - type: Documentation
    url: https://docs.customeros.ai
common:
- type: Website
  url: https://customeros.ai
- type: Documentation
  url: https://docs.customeros.ai
- type: GettingStarted
  url: https://docs.customeros.ai/quickstart
- type: Blog
  url: https://customeros.ai/gtm-guides
- type: Pricing
  url: https://customeros.ai/pricing
- type: Login
  url: https://app.customeros.ai/signin
- type: TermsOfService
  url: https://customeros.ai/standard-agreement/tos
- type: PrivacyPolicy
  url: https://customeros.ai/policies/privacy-policy
- type: GitHubOrganization
  url: https://github.com/customeros
- type: LinkedIn
  url: https://www.linkedin.com/company/customeros
- type: StatusPage
  url: https://status.customeros.ai/
- type: Compliance
  url: https://docs.customeros.ai/security-and-compliance
- type: ChangeLog
  url: https://customeros.ai/updates
- type: ChangeLog
  url: changelog/customeros-changelog.yml
- type: AgentCard
  url: a2a/customeros-a2a.yml
- type: MCPServer
  url: mcp/customeros-mcp.yml
- type: ToolCrosswalk
  url: mcp/customeros-tool-crosswalk.yml
- type: AgentSkill
  url: skills/_index.yml
- type: LLMsTxt
  url: llms/customeros-llms.txt
- type: WellKnown
  url: well-known/customeros-well-known.yml
- type: AgenticAccess
  url: agentic-access/customeros-agentic-access.yml
- type: Authentication
  url: authentication/customeros-authentication.yml
- type: Conventions
  url: conventions/customeros-conventions.yml
- type: ErrorCatalog
  url: errors/customeros-problem-types.yml
- type: Lifecycle
  url: lifecycle/customeros-lifecycle.yml
- type: Conformance
  url: conformance/customeros-conformance.yml
- type: DataModel
  url: data-model/customeros-data-model.yml
- type: Components
  url: components/customeros-components.yml
- type: Packages
  url: packages/customeros-packages.yml
- type: Protobuf
  url: grpc/_index.yml
- type: TrustCenter
  url: security/customeros-trust-center.yml
- type: DomainSecurity
  url: security/customeros-domain-security.yml
- type: Plans
  url: plans/customeros-plans-pricing.yml
- type: RateLimits
  url: rate-limits/customeros-rate-limits.yml
- type: FinOps
  url: finops/customeros-finops.yml
- type: Overlay
  url: overlays/customeros-customerbase-overlay.yaml
- type: Overlay
  url: overlays/customeros-enrich-overlay.yaml
- type: Overlay
  url: overlays/customeros-verify-overlay.yaml
- type: Overlay
  url: overlays/customeros-domains-overlay.yaml
- type: Overlay
  url: overlays/customeros-billing-overlay.yaml
- type: Overlay
  url: overlays/customeros-outreach-overlay.yaml
- type: Overlay
  url: overlays/customeros-flow-api-overlay.yaml
- type: Overlay
  url: overlays/customeros-graphql-api-overlay.yaml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
x-enrichment:
  date: '2026-08-13'
  status: enriched
  artifacts_added: 32
  pass: local-v1

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