Inflection.io

Inflection.io is a B2B marketing automation platform positioned as a modern, AI-native replacement for legacy tools like Marketo. It unifies target accounts, product users, customers, and leads with product-usage, sales, and behavioral signals so marketing teams can build audiences, draft campaigns, map customer journeys, score accounts, and report to the CMO — executing in minutes rather than weeks. The Inflection Developer API is a JSON-over-HTTPS REST API (OpenAPI 3.1, base https://api.inflection.io/v1) for reading and writing the people in a workspace: their profiles, product and marketing activity, static lists, and email templates, authenticated with scoped Personal Access Tokens. Surfaced as a version-one-ventures portfolio company and enriched from the provider's public developer API surface.

Inflection.io publishes 4 APIs on the APIs.io network, including Contact Activity API, Contacts API, Email Templates API, and 1 more. Tagged areas include Company, Saas, Marketing, Marketing Automation, and Email Marketing.

Inflection.io’s developer surface includes documentation, API reference, getting-started guide, support, engineering blog, pricing, signup flow, and 21 more developer resources.

🌐 Visit website 📡 Source on GitHub

47.5/100 developing ▬ flat Agent 69/100 agent native Full breakdown ↓
scored 2026-07-27 · rubric v0.5

AccessSelf serve

4 APIs 1 MCP Servers

CompanySaasMarketingMarketing AutomationEmail MarketingCustomer DataB2BContactsAPI

Kin Score

Kin Score How this is scored →
scored 2026-07-27 · rubric v0.5

Composite quality — 47.5/100 · developing

Contract Quality 14.4 / 25

Developer Ergonomics 13.5 / 20

Commercial Clarity 8.9 / 20

Operational Transparency 0.7 / 13

Governance 0.0 / 12

Discoverability 10.0 / 10

Agent readiness — 69/100 · agent native

Machine-Readable Contract 18 / 18

Agentic Access Contract 15 / 15

MCP Server 12 / 12

Machine-Readable Auth 10 / 10

Idempotency 0 / 9

Stable Error Semantics 8 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 0 / 7

Typed Event Surface 0 / 6

Agent Skills 5 / 5

Well-Known Catalog 4 / 4

Consent & Bot Identity 0 / 3

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/inflectionio: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

APIs 4

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

MCP Servers 1

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

Get Started 4

Portal, sign-up, and the first successful call

DeveloperPortal

DeveloperPortal

GettingStarted

GettingStarted

SignUp

SignUp

Login

Documentation 3

Reference material describing how the API behaves

Documentation

Documentation

APIReference

APIReference

OpenAPI

OpenAPI

Agent Surfaces 5

MCP servers, agent skills, and machine-readable catalogs

MCPServer

AgentSkill

WellKnown

LLMsTxt

AgenticAccess

Design & Contract 5

Pagination, idempotency, versioning, errors, and events

Conventions

ErrorCatalog

DataModel

Lifecycle

Conformance

Build 1

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

GitHubOrganization

Access & Security 2

Authentication, authorization, and security posture

Authentication

Authentication

DomainSecurity

DomainSecurity

Operate 2

Status, limits, changes, and where to get help

HelpCenter

HelpCenter

Support

Support

Commercial 3

Pricing, plans, and the legal terms of use

Pricing

Pricing

TermsOfService

TermsOfService

PrivacyPolicy

PrivacyPolicy

Company 2

The organization behind the API

Website

Website

Blog

Blog

Other 1

Properties that don't map to a standard resource type

Overlay

Overlay

Source (apis.yml)

aid: inflectionio
name: Inflection.io
description: 'Inflection.io is a B2B marketing automation platform positioned as a modern, AI-native replacement for legacy
  tools like Marketo. It unifies target accounts, product users, customers, and leads with product-usage, sales, and behavioral
  signals so marketing teams can build audiences, draft campaigns, map customer journeys, score accounts, and report to the
  CMO — executing in minutes rather than weeks. The Inflection Developer API is a JSON-over-HTTPS REST API (OpenAPI 3.1, base
  https://api.inflection.io/v1) for reading and writing the people in a workspace: their profiles, product and marketing activity,
  static lists, and email templates, authenticated with scoped Personal Access Tokens. Surfaced as a version-one-ventures
  portfolio company and enriched from the provider''s public developer API surface.'
url: https://raw.githubusercontent.com/api-evangelist/inflectionio/refs/heads/main/apis.yml
accessModel:
  pricing: unknown
  onboarding: self-serve
  trial: false
  try_now: false
  public: false
  label: Self-serve signup
  confidence: medium
  source:
  - authentication
  generated: '2026-07-22'
  method: derived
image: https://www.inflection.io/img/asset/YXNzZXRzL29nLWltYWdlLmpwZw/og-image.jpg
x-type: company
x-source: vc-portfolio
x-backed-by:
- version-one-ventures
x-tier: enriched
x-tier-reason: public-developer-api
specificationVersion: '0.20'
created: '2026-07-17'
modified: '2026-07-19'
tags:
- Company
- Saas
- Marketing
- Marketing Automation
- Email Marketing
- Customer Data
- B2B
- Contacts
- API
apis:
- aid: inflectionio:inflectionio-contact-activity-api
  name: Inflection.io Contact Activity API
  description: The Contact Activity API from Inflection.io — 4 operation(s) for contact activity.
  humanURL: https://github.com/inflectionio/mintlify-docs/blob/develop/api-reference/introduction.mdx
  baseURL: https://api.inflection.io/v1
  tags:
  - Contact Activity
  properties:
  - type: OpenAPI
    url: openapi/inflectionio-contact-activity-api-openapi.yml
  - type: Documentation
    url: https://github.com/inflectionio/mintlify-docs/tree/develop/api-reference
  - type: APIReference
    url: https://api.inflection.io/docs
- aid: inflectionio:inflectionio-contacts-api
  name: Inflection.io Contacts API
  description: The Contacts API from Inflection.io — 5 operation(s) for contacts.
  humanURL: https://github.com/inflectionio/mintlify-docs/blob/develop/api-reference/introduction.mdx
  baseURL: https://api.inflection.io/v1
  tags:
  - Contacts
  properties:
  - type: OpenAPI
    url: openapi/inflectionio-contacts-api-openapi.yml
  - type: Documentation
    url: https://github.com/inflectionio/mintlify-docs/tree/develop/api-reference
  - type: APIReference
    url: https://api.inflection.io/docs
- aid: inflectionio:inflectionio-email-templates-api
  name: Inflection.io Email Templates API
  description: The Email Templates API from Inflection.io — 1 operation(s) for email templates.
  humanURL: https://github.com/inflectionio/mintlify-docs/blob/develop/api-reference/introduction.mdx
  baseURL: https://api.inflection.io/v1
  tags:
  - Email Templates
  properties:
  - type: OpenAPI
    url: openapi/inflectionio-email-templates-api-openapi.yml
  - type: Documentation
    url: https://github.com/inflectionio/mintlify-docs/tree/develop/api-reference
  - type: APIReference
    url: https://api.inflection.io/docs
- aid: inflectionio:inflectionio-lists-and-members-api
  name: Inflection.io Lists and Members API
  description: The Lists and Members API from Inflection.io — 4 operation(s) for lists and members.
  humanURL: https://github.com/inflectionio/mintlify-docs/blob/develop/api-reference/introduction.mdx
  baseURL: https://api.inflection.io/v1
  tags:
  - Lists and Members
  properties:
  - type: OpenAPI
    url: openapi/inflectionio-lists-and-members-api-openapi.yml
  - type: Documentation
    url: https://github.com/inflectionio/mintlify-docs/tree/develop/api-reference
  - type: APIReference
    url: https://api.inflection.io/docs
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: Website
  url: https://www.inflection.io
- type: DeveloperPortal
  url: https://github.com/inflectionio/mintlify-docs/tree/develop/api-reference
- type: Documentation
  url: https://github.com/inflectionio/mintlify-docs/tree/develop/api-reference
- type: APIReference
  url: https://api.inflection.io/docs
- type: GettingStarted
  url: https://github.com/inflectionio/mintlify-docs/blob/develop/api-reference/quickstart.mdx
- type: HelpCenter
  url: https://docs.inflection.io
- type: Support
  url: https://docs.inflection.io
- type: Blog
  url: https://www.inflection.io/blog
- type: Pricing
  url: https://www.inflection.io/pricing
- type: SignUp
  url: https://app.inflection.io/login/start
- type: Login
  url: https://app.inflection.io/login/start
- type: TermsOfService
  url: https://www.inflection.io/legal/terms
- type: PrivacyPolicy
  url: https://www.inflection.io/legal/privacy-policy
- type: GitHubOrganization
  url: https://github.com/inflectionio
- type: OpenAPI
  url: openapi/inflectionio-openapi-original.yml
- type: Overlay
  url: overlays/inflectionio-openapi-overlay.yaml
- type: Authentication
  url: authentication/inflectionio-authentication.yml
- type: Conventions
  url: conventions/inflectionio-conventions.yml
- type: ErrorCatalog
  url: errors/inflectionio-problem-types.yml
- type: DataModel
  url: data-model/inflectionio-data-model.yml
- type: Lifecycle
  url: lifecycle/inflectionio-lifecycle.yml
- type: Conformance
  url: conformance/inflectionio-conformance.yml
- type: MCPServer
  url: mcp/inflectionio-mcp.yml
- type: AgentSkill
  url: skills/_index.yml
- type: WellKnown
  url: well-known/inflectionio-well-known.yml
- type: LLMsTxt
  url: llms/inflectionio-llms.txt
- type: AgenticAccess
  url: agentic-access/inflectionio-agentic-access.yml
- type: DomainSecurity
  url: security/inflectionio-domain-security.yml
x-enrichment:
  date: '2026-07-19'
  status: backfilled
  pass: local-v1
  note: backfilled from .gitignore signal + verified work evidence

Inflection.io

Kin Score

APIs 4

Inflection.io Contact Activity API

Inflection.io Contacts API

Inflection.io Email Templates API

Inflection.io Lists and Members API

MCP Servers 1

inflectionio-mcp.yml

Security Posture 2

Inflectionio Authentication

Inflectionio Domain Security

Agentic Access 1

Inflectionio Agentic Access

Resources