Epsilon

Epsilon is a Publicis Groupe marketing and advertising technology company that operates identity-led, data-driven marketing across paid, owned and earned channels. Its public, machine-readable API surface sits almost entirely inside Epsilon Retail Media (the platform built on CitrusAd, which Publicis acquired in 2021 and folded into Epsilon), whose developer hub at developers.citrusad.com publishes an Integration API for syncing catalogs, products, customers and orders and for generating product, banner and Banner X ads; a Filter Mapping API; a Cross-Sell Category API; and a Brand Pages API served from regional *.rmn.dotomi.com hosts. Epsilon also runs Epsilon PeopleCloud (loyalty, CRM, digital media) and CORE Private Exchange for publishers, but neither publishes a public machine-readable contract. API access is provisioned by a Technical Account Manager rather than self-service signup.

Epsilon publishes 7 APIs on the APIs.io network, including Ads API, Catalog Products API, Catalogs API, and 4 more. Tagged areas include Company, Marketing, Advertising, Retail Media, and Advertising Technology.

Epsilon’s developer surface includes documentation, API reference, getting-started guide, support, engineering blog, authentication, sandbox, and 21 more developer resources.

🌐 Visit website 📡 Source on GitHub

36.0/100 thin ▬ flat Agent 30/100 agent ready saas Full breakdown ↓
scored 2026-09-08 · rubric v0.20.0

AccessSelf serve

3 APIs

Company Marketing Advertising Retail Media Advertising Technology Identity Resolution Customer Data Loyalty RetailPublicis Groupe

Kin Score

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

Composite quality — 36.0/100 · thin

Contract Quality 11.9 / 23

Developer Ergonomics 5.0 / 18

Access Clarity 3.8 / 18

Operational Transparency 0.0 / 12

Contract Governance 2.0 / 11

Discoverability 8.3 / 9

Create-or-Update Ergonomics 2.2 / 10

Agent readiness — 30/100 · agent ready

Machine-Readable Contract 18 / 18

Agentic Access Contract 0 / 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 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/epsilon: 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 8

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

Epsilon Retail Media Brand Pages API

Serves brand-page content modules for retailer-hosted brand landing pages. A retailer routes /brands/{slug} on its own domain, calls POST /ads/v3/brand-pages on its assigned reg...

Epsilon Ads API

The Ads API from Epsilon — 2 operation(s) for ads.

Epsilon Catalog Products API

The Catalog Products API from Epsilon — 2 operation(s) for catalog products.

Epsilon Catalogs API

The Catalogs API from Epsilon — 1 operation(s) for catalogs.

Epsilon Cross Sell Category API

The crossSellCategory API from Epsilon — 2 operation(s) for crosssellcategory.

Epsilon Customers API

The Customers API from Epsilon — 3 operation(s) for customers.

Epsilon Filter Mapping API

The filterMapping API from Epsilon — 2 operation(s) for filtermapping.

Epsilon Orders API

The Orders API from Epsilon — 2 operation(s) for orders.

Scroll for all 8

Open Collections 3

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

CrossSellCategory API

OPEN COLLECTION

Citrus filter-mapping API

OPEN COLLECTION

Epsilon Retail Media Integration API

OPEN COLLECTION

Pricing Plans 1

Published pricing tiers and plan structures.

Epsilon Plans Pricing

0 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Epsilon Rate Limits

0 limits

RATE LIMITS

Security Posture 2

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

Epsilon Authentication

apiKey/http-basic/oauth2/jwt-bearer · 4 schemes

SECURITY

Epsilon Domain Security

TLSv1.2 · HSTS · DMARC

SECURITY

Resources

Get Started 3

Portal, sign-up, and the first successful call

DeveloperPortal

DeveloperPortal

GettingStarted

GettingStarted

Sandbox

Sandbox

Documentation 2

Reference material describing how the API behaves

Documentation

Documentation

APIReference

APIReference

Agent Surfaces 3

MCP servers, agent skills, and machine-readable catalogs

LLMsTxt

LLMsTxt

WellKnown

WellKnown

AgentSkill

AgentSkill

Design & Contract 5

Pagination, idempotency, versioning, errors, and events

Conventions

ErrorCatalog

Lifecycle

Conformance

DataModel

Build 1

SDKs, sample code, and the tooling you integrate with

Packages

Packages

Access & Security 2

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Authentication

Authentication

Operate 2

Status, limits, changes, and where to get help

Support

Support

RateLimits

RateLimits

Commercial 3

Pricing, plans, and the legal terms of use

TermsOfService

TermsOfService

PrivacyPolicy

PrivacyPolicy

Plans

Plans

Company 2

The organization behind the API

Website

Website

Blog

Blog

Other 5

Properties that don't map to a standard resource type

CapabilityMap

Overlay

Overlay

Overlay

APICatalog

Source (apis.yml)

aid: epsilon
name: Epsilon
description: Epsilon is a Publicis Groupe marketing and advertising technology company that operates identity-led, data-driven
  marketing across paid, owned and earned channels. Its public, machine-readable API surface sits almost entirely inside Epsilon
  Retail Media (the platform built on CitrusAd, which Publicis acquired in 2021 and folded into Epsilon), whose developer
  hub at developers.citrusad.com publishes an Integration API for syncing catalogs, products, customers and orders and for
  generating product, banner and Banner X ads; a Filter Mapping API; a Cross-Sell Category API; and a Brand Pages API served
  from regional *.rmn.dotomi.com hosts. Epsilon also runs Epsilon PeopleCloud (loyalty, CRM, digital media) and CORE Private
  Exchange for publishers, but neither publishes a public machine-readable contract. API access is provisioned by a Technical
  Account Manager rather than self-service signup.
url: https://raw.githubusercontent.com/api-evangelist/epsilon/refs/heads/main/apis.yml
deliveryModel:
  model: saas
  open_source: false
  commercial: true
  callable_host: false
  label: Hosted service · you call their endpoint
  confidence: medium
  source:
  - openapi
  - pricing
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: unknown
  onboarding: self-serve
  trial: false
  try_now: false
  public: false
  label: Self-serve signup
  confidence: medium
  source:
  - authentication
  - rate-limits
  - security
  - sandbox
  generated: '2026-09-02'
  method: derived
image: https://www.epsilon.com/images/logos/epsilon-og-image.png
x-type: company
x-source: harvest:marketing-integration-graph
specificationVersion: '0.23'
created: '2026-08-12'
modified: '2026-08-12'
tags:
- Company
- Marketing
- Advertising
- Retail Media
- Advertising Technology
- Identity Resolution
- Customer Data
- Loyalty
- Retail
- Publicis Groupe
apis:
- aid: epsilon:epsilon-retail-media-brand-pages-api
  name: Epsilon Retail Media Brand Pages API
  description: Serves brand-page content modules for retailer-hosted brand landing pages. A retailer routes /brands/{slug}
    on its own domain, calls POST /ads/v3/brand-pages on its assigned regional Epsilon RMN ads host with the urlSlug and catalogId,
    and renders the returned modules, theme and tracking templates with its own UI components. Impression, click and add-to-cart
    tracking is fired either client-to-server through a retailer reverse proxy or server-to-server directly to the regional
    tracking host. Uses the same API key as the rest of the Epsilon RMN platform. No OpenAPI is published for this surface;
    the request and response contracts are documented in prose.
  humanURL: https://developers.citrusad.com/integration/reference/brand-page-apis
  baseURL: https://eu-ads.rmn.dotomi.com
  tags:
  - Retail Media
  - Advertising
  - Brand Pages
  - Content
  properties:
  - type: Documentation
    url: https://developers.citrusad.com/integration/reference/overview-1
  - type: APIReference
    url: https://developers.citrusad.com/integration/reference/brand-page-apis
- aid: epsilon:epsilon-ads-api
  name: Epsilon Ads API
  description: The Ads API from Epsilon — 2 operation(s) for ads.
  humanURL: https://developers.citrusad.com/integration/reference/api-overview
  baseURL: https://integration-{tenant}.citrusad.com/v1
  tags:
  - Ads
  properties:
  - type: OpenAPI
    url: openapi/epsilon-ads-api-openapi.yml
  - type: Documentation
    url: https://developers.citrusad.com/integration/reference/api-overview
  - type: APIReference
    url: https://developers.citrusad.com/integration/reference/generate
  - type: APIReference
    url: https://developers.citrusad.com/integration/reference/filtermapping
  - type: APIReference
    url: https://developers.citrusad.com/integration/reference/crosssellcategory
- aid: epsilon:epsilon-catalog-products-api
  name: Epsilon Catalog Products API
  description: The Catalog Products API from Epsilon — 2 operation(s) for catalog products.
  humanURL: https://developers.citrusad.com/integration/reference/api-overview
  baseURL: https://integration-{tenant}.citrusad.com/v1
  tags:
  - Catalog Products
  properties:
  - type: OpenAPI
    url: openapi/epsilon-catalog-products-api-openapi.yml
  - type: Documentation
    url: https://developers.citrusad.com/integration/reference/api-overview
  - type: APIReference
    url: https://developers.citrusad.com/integration/reference/generate
  - type: APIReference
    url: https://developers.citrusad.com/integration/reference/filtermapping
  - type: APIReference
    url: https://developers.citrusad.com/integration/reference/crosssellcategory
- aid: epsilon:epsilon-catalogs-api
  name: Epsilon Catalogs API
  description: The Catalogs API from Epsilon — 1 operation(s) for catalogs.
  humanURL: https://developers.citrusad.com/integration/reference/api-overview
  baseURL: https://integration-{tenant}.citrusad.com/v1
  tags:
  - Catalogs
  properties:
  - type: OpenAPI
    url: openapi/epsilon-catalogs-api-openapi.yml
  - type: Documentation
    url: https://developers.citrusad.com/integration/reference/api-overview
  - type: APIReference
    url: https://developers.citrusad.com/integration/reference/generate
  - type: APIReference
    url: https://developers.citrusad.com/integration/reference/filtermapping
  - type: APIReference
    url: https://developers.citrusad.com/integration/reference/crosssellcategory
- aid: epsilon:epsilon-crosssellcategory-api
  name: Epsilon Cross Sell Category API
  description: The crossSellCategory API from Epsilon — 2 operation(s) for crosssellcategory.
  humanURL: https://developers.citrusad.com/integration/reference/api-overview
  baseURL: https://integration-{tenant}.citrusad.com/v1
  tags: []
  tags_raw:
  - crossSellCategory
  properties:
  - type: OpenAPI
    url: openapi/epsilon-crosssellcategory-api-openapi.yml
  - type: Documentation
    url: https://developers.citrusad.com/integration/reference/api-overview
  - type: APIReference
    url: https://developers.citrusad.com/integration/reference/generate
  - type: APIReference
    url: https://developers.citrusad.com/integration/reference/filtermapping
  - type: APIReference
    url: https://developers.citrusad.com/integration/reference/crosssellcategory
- aid: epsilon:epsilon-customers-api
  name: Epsilon Customers API
  description: The Customers API from Epsilon — 3 operation(s) for customers.
  humanURL: https://developers.citrusad.com/integration/reference/api-overview
  baseURL: https://integration-{tenant}.citrusad.com/v1
  tags:
  - Customers
  properties:
  - type: OpenAPI
    url: openapi/epsilon-customers-api-openapi.yml
  - type: Documentation
    url: https://developers.citrusad.com/integration/reference/api-overview
  - type: APIReference
    url: https://developers.citrusad.com/integration/reference/generate
  - type: APIReference
    url: https://developers.citrusad.com/integration/reference/filtermapping
  - type: APIReference
    url: https://developers.citrusad.com/integration/reference/crosssellcategory
- aid: epsilon:epsilon-filtermapping-api
  name: Epsilon Filter Mapping API
  description: The filterMapping API from Epsilon — 2 operation(s) for filtermapping.
  humanURL: https://developers.citrusad.com/integration/reference/api-overview
  baseURL: https://integration-{tenant}.citrusad.com/v1
  tags: []
  tags_raw:
  - filterMapping
  properties:
  - type: OpenAPI
    url: openapi/epsilon-filtermapping-api-openapi.yml
  - type: Documentation
    url: https://developers.citrusad.com/integration/reference/api-overview
  - type: APIReference
    url: https://developers.citrusad.com/integration/reference/generate
  - type: APIReference
    url: https://developers.citrusad.com/integration/reference/filtermapping
  - type: APIReference
    url: https://developers.citrusad.com/integration/reference/crosssellcategory
- aid: epsilon:epsilon-orders-api
  name: Epsilon Orders API
  description: The Orders API from Epsilon — 2 operation(s) for orders.
  humanURL: https://developers.citrusad.com/integration/reference/api-overview
  baseURL: https://integration-{tenant}.citrusad.com/v1
  tags:
  - Order
  tags_raw:
  - Orders
  properties:
  - type: OpenAPI
    url: openapi/epsilon-orders-api-openapi.yml
  - type: Documentation
    url: https://developers.citrusad.com/integration/reference/api-overview
  - type: APIReference
    url: https://developers.citrusad.com/integration/reference/generate
  - type: APIReference
    url: https://developers.citrusad.com/integration/reference/filtermapping
  - type: APIReference
    url: https://developers.citrusad.com/integration/reference/crosssellcategory
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: CapabilityMap
  url: capabilities/epsilon-capability-edges.yml
  name: Epsilon Business Capability Map
- type: Overlay
  url: overlays/epsilon-retail-media-integration-overlay.yaml
- type: Overlay
  url: overlays/epsilon-retail-media-filter-mapping-overlay.yaml
- type: Overlay
  url: overlays/epsilon-retail-media-cross-sell-category-overlay.yaml
- type: DomainSecurity
  url: security/epsilon-domain-security.yml
- type: Website
  url: https://epsilon.com/
- type: DeveloperPortal
  url: https://developers.citrusad.com/integration/reference/overview
- type: Documentation
  url: https://developers.citrusad.com/integration/reference/api-overview
- type: APIReference
  url: https://developers.citrusad.com/integration/reference/generate
- type: GettingStarted
  url: https://developers.citrusad.com/integration/reference/before-you-start
- type: Support
  url: https://help-center.peoplecloud.epsilon.com/
- type: Blog
  url: https://www.epsilon.com/us/insights/blog
- type: TermsOfService
  url: https://legal.epsilon.com/us/terms-and-conditions
- type: PrivacyPolicy
  url: https://legal.epsilon.com/global-privacy-policies
- type: LLMsTxt
  url: llms/epsilon-llms.txt
- type: WellKnown
  url: well-known/epsilon-well-known.yml
- type: APICatalog
  url: https://developers.citrusad.com/.well-known/api-catalog
- type: Authentication
  url: authentication/epsilon-authentication.yml
- type: Conventions
  url: conventions/epsilon-conventions.yml
- type: ErrorCatalog
  url: errors/epsilon-problem-types.yml
- type: Lifecycle
  url: lifecycle/epsilon-lifecycle.yml
- type: Conformance
  url: conformance/epsilon-conformance.yml
- type: DataModel
  url: data-model/epsilon-data-model.yml
- type: Sandbox
  url: sandbox/epsilon-sandbox.yml
- type: Packages
  url: packages/epsilon-packages.yml
- type: Plans
  url: plans/epsilon-plans-pricing.yml
- type: RateLimits
  url: rate-limits/epsilon-rate-limits.yml
- type: AgentSkill
  url: skills/_index.yml
x-vouched-by:
- Persado
- mParticle
x-vouch-count: 2
x-enrichment:
  date: '2026-08-12'
  status: enriched
  artifacts_added: 26
  pass: local-v1

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