lemlist

lemlist is a sales engagement and cold outreach platform from lempire that helps sales teams build prospect lists, personalize multichannel campaigns across email, LinkedIn, phone, SMS and WhatsApp, and automate follow-ups to book more meetings. It includes a 650M+ record B2B lead database, credit-metered email and phone enrichment, Signal Agents that watch for buying triggers, a unified reply inbox, and lemwarm deliverability warm-up. The developer surface is unusually agent-forward for its category - a 143-operation REST API documented with a published OpenAPI, a hosted remote MCP server at app.lemlist.com/mcp with OAuth 2.1 and dynamic client registration, an official OpenAPI-generated CLI on npm, an llms.txt index, a published Agent Skill, and a 76-event webhook catalog.

lemlist publishes 21 APIs on the APIs.io network, including REST API, Campaigns API, Sequences API, and 18 more. Tagged areas include Email Outreach, Sales Engagement, Cold Email, Sales Automation, and LinkedIn Outreach.

The lemlist catalog on APIs.io includes 1 event-driven AsyncAPI specification.

lemlist’s developer surface includes documentation, API reference, getting-started guide, support, engineering blog, pricing, signup flow, and 36 more developer resources.

🌐 Visit website 📡 Source on GitHub

68.0/100 exemplar ▬ flat Agent 62/100 agent ready Full breakdown ↓
scored 2026-08-21 · rubric v0.12.0

AccessPaidSelf serveFree trial

22 APIs 1 MCP Servers

Email Outreach Sales Engagement Cold Email Sales AutomationLinkedIn OutreachLead Generation Data Enrichment Deliverability CRMMultichannel MessagingWebhook MCP

Kin Score

Kin Score How this is scored →
scored 2026-08-21 · rubric v0.12.0

Composite quality — 68.0/100 · exemplar

Contract Quality 15.8 / 25

Developer Ergonomics 15.7 / 20

Access Clarity 17.1 / 20

Operational Transparency 6.5 / 13

Contract Governance 3.6 / 12

Discoverability 9.3 / 10

Agent readiness — 62/100 · 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 6 / 6

Agent Skills 5 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 8 / 8

Dry-Run / Simulate Mode 0 / 4

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/lemlist: 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 22

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.

lemlist MCP Server

MCP SERVER

GraphQL 1

GraphQL schemas published by this provider.

Rate Limits 1

Documented rate limits and quota policies.

Examples 1

Example request and response payloads for these APIs.

Scopes 1

OAuth scopes governing access to this provider's APIs.

Lemlist Scopes

14 scopes · authorizationCode

14 scopes

SCOPES

Get Started 4

Portal, sign-up, and the first successful call

DeveloperPortal

DeveloperPortal

GettingStarted

GettingStarted

SignUp

SignUp

Login

Documentation 2

Reference material describing how the API behaves

Documentation

Documentation

APIReference

APIReference

Agent Surfaces 6

MCP servers, agent skills, and machine-readable catalogs

WellKnown

MCPServer

AgentSkill

AgenticAccess

LLMsTxt

LlmsText

Design & Contract 6

Pagination, idempotency, versioning, errors, and events

Conventions

ErrorCatalog

DataModel

Lifecycle

Conformance

Webhooks

Build 5

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

Examples

Packages

SDKs

CLI

Access & Security 7

Authentication, authorization, and security posture

Authentication

OAuthScopes

Compliance

TrustCenter

Security

VulnerabilityDisclosure

VulnerabilityDisclosure

DomainSecurity

DomainSecurity

Scroll for all 7

Operate 4

Status, limits, changes, and where to get help

Support

RateLimits

StatusPage

Deprecation

Commercial 4

Pricing, plans, and the legal terms of use

Pricing

TermsOfService

PrivacyPolicy

Plans

Company 3

The organization behind the API

Website

Website

Blog

Blog

LinkedIn

Other 2

Properties that don't map to a standard resource type

Overlay

Overlay

AgentCard

AgentCard

Source (apis.yml)

aid: lemlist
name: lemlist
description: lemlist is a sales engagement and cold outreach platform from lempire that helps sales teams build prospect lists,
  personalize multichannel campaigns across email, LinkedIn, phone, SMS and WhatsApp, and automate follow-ups to book more
  meetings. It includes a 650M+ record B2B lead database, credit-metered email and phone enrichment, Signal Agents that watch
  for buying triggers, a unified reply inbox, and lemwarm deliverability warm-up. The developer surface is unusually agent-forward
  for its category - a 143-operation REST API documented with a published OpenAPI, a hosted remote MCP server at app.lemlist.com/mcp
  with OAuth 2.1 and dynamic client registration, an official OpenAPI-generated CLI on npm, an llms.txt index, a published
  Agent Skill, and a 76-event webhook catalog.
type: Index
accessModel:
  pricing: paid
  onboarding: self-serve
  trial: true
  try_now: false
  public: true
  label: Self-serve signup with a 14-day free trial
  confidence: high
  source:
  - https://www.lemlist.com/pricing
  - https://app.lemlist.com/create-account
  generated: '2026-08-13'
  method: searched
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/lemlist.png
tags:
- Email Outreach
- Sales Engagement
- Cold Email
- Sales Automation
- LinkedIn Outreach
- Lead Generation
- Data Enrichment
- Deliverability
- CRM
- Multichannel Messaging
- Webhook
- MCP
tags_raw:
- Email Outreach
- Sales Engagement
- Cold Email
- Sales Automation
- LinkedIn Outreach
- Lead Generation
- Data Enrichment
- Deliverability
- CRM
- Multichannel Messaging
- Webhooks
- MCP
url: https://raw.githubusercontent.com/api-evangelist/lemlist/refs/heads/main/apis.yml
created: '2026-05-11'
modified: '2026-08-13'
specificationVersion: '0.23'
apis:
- aid: lemlist:rest-api
  name: lemlist REST API
  description: The full lemlist REST API - 143 operations across campaigns, sequences, leads, contacts, companies, the B2B
    people database, enrichment, the unified inbox, Signal Agents, unsubscribes, webhooks, lemwarm and deliverability alerts.
    All routes live under https://api.lemlist.com/api. Authentication is an API key carried as HTTP Basic with an empty username.
    lemlist publishes the OpenAPI at developer.lemlist.com/api-reference/openapi/v2.json.
  humanURL: https://developer.lemlist.com
  baseURL: https://api.lemlist.com/api
  tags:
  - Email Outreach
  - Sales Engagement
  - Cold Email
  - Sales Automation
  properties:
  - type: OpenAPI
    url: openapi/_original/lemlist-openapi-v2.json
  - type: Documentation
    url: https://developer.lemlist.com
  - type: APIReference
    url: https://developer.lemlist.com/api-reference/getting-started/overview
  - type: GettingStarted
    url: https://developer.lemlist.com/api-reference/getting-started/overview
  - type: Examples
    url: examples/lemlist-examples.yml
  - type: Overlay
    url: overlays/lemlist-api-overlay.yaml
  - type: DataModel
    url: data-model/lemlist-data-model.yml
- aid: lemlist:mcp-server
  name: lemlist MCP Server
  description: lemlist's hosted remote Model Context Protocol server. An MCP client POSTs to https://app.lemlist.com/mcp and
    authenticates with OAuth 2.1 (authorization code + PKCE, dynamic client registration) or an X-API-Key header. lemlist
    advertises roughly 40 tools covering lead search, enrichment, campaign and sequence management, stats, the inbox and webhooks.
  humanURL: https://developer.lemlist.com/mcp/setup
  baseURL: https://app.lemlist.com/mcp
  tags:
  - MCP
  - Agents
  properties:
  - type: MCPServer
    url: mcp/lemlist-mcp.yml
  - type: ToolCrosswalk
    url: mcp/lemlist-tool-crosswalk.yml
  - type: Documentation
    url: https://developer.lemlist.com/mcp/setup
- aid: lemlist:lemlist-campaigns-api
  name: lemlist Campaigns API
  description: Campaign CRUD and lifecycle - create, update, duplicate, start, pause, validation statutes, stats, reports
    and asynchronous exports.
  humanURL: https://developer.lemlist.com/api-reference/endpoints/campaigns/get-many-campaigns
  baseURL: https://api.lemlist.com/api
  tags:
  - Campaigns
  properties:
  - type: OpenAPI
    url: openapi/lemlist-campaigns-api-openapi.yml
- aid: lemlist:lemlist-sequences-api
  name: lemlist Sequences API
  description: Campaign sequences, their steps, and A/B test variants on email steps.
  humanURL: https://developer.lemlist.com/api-reference/endpoints/sequences/get-campaign-sequences
  baseURL: https://api.lemlist.com/api
  tags:
  - Sequences
  properties:
  - type: OpenAPI
    url: openapi/lemlist-sequences-api-openapi.yml
- aid: lemlist:lemlist-leads-api
  name: lemlist Leads API
  description: Leads inside campaigns - create with optional enrichment, update, pause, resume, mark interested, custom variables,
    CRM import and unsubscribe.
  humanURL: https://developer.lemlist.com/api-reference/endpoints/leads/create-lead-in-campaign
  baseURL: https://api.lemlist.com/api
  tags:
  - Leads
  properties:
  - type: OpenAPI
    url: openapi/lemlist-leads-api-openapi.yml
- aid: lemlist:lemlist-people-database-api
  name: lemlist People Database API
  description: Search the lemlist B2B people and company database, list its filters, and manage saved personas.
  humanURL: https://developer.lemlist.com/api-reference/endpoints/people-database/search-people-database
  baseURL: https://api.lemlist.com/api
  tags:
  - People Database
  - Lead Generation
  properties:
  - type: OpenAPI
    url: openapi/lemlist-people-database-api-openapi.yml
- aid: lemlist:lemlist-enrich-api
  name: lemlist Enrich API
  description: Asynchronous enrichment - find and verify emails, phone numbers and LinkedIn data, single or in bulk, then
    poll for the result. Credit-metered.
  humanURL: https://developer.lemlist.com/api-reference/endpoints/enrich/enrich-data
  baseURL: https://api.lemlist.com/api
  tags:
  - Enrich
  - Data Enrichment
  properties:
  - type: OpenAPI
    url: openapi/lemlist-enrich-api-openapi.yml
- aid: lemlist:lemlist-inbox-api
  name: lemlist Inbox API
  description: The unified reply inbox - conversations, messages, drafts, labels and sending on email, LinkedIn and WhatsApp.
  humanURL: https://developer.lemlist.com/api-reference
  baseURL: https://api.lemlist.com/api
  tags:
  - Inbox
  - Multichannel Messaging
  properties:
  - type: OpenAPI
    url: openapi/lemlist-inbox-api-openapi.yml
- aid: lemlist:lemlist-contacts-api
  name: lemlist Contacts API
  description: CRM-side contacts, contact lists, list membership and exports.
  humanURL: https://developer.lemlist.com/api-reference
  baseURL: https://api.lemlist.com/api
  tags:
  - Contacts
  - CRM
  properties:
  - type: OpenAPI
    url: openapi/lemlist-contacts-api-openapi.yml
- aid: lemlist:lemlist-companies-api
  name: lemlist Companies API
  description: CRM-side companies and company notes.
  humanURL: https://developer.lemlist.com/api-reference
  baseURL: https://api.lemlist.com/api
  tags:
  - Companies
  - CRM
  properties:
  - type: OpenAPI
    url: openapi/lemlist-companies-api-openapi.yml
- aid: lemlist:lemlist-signal-agents-api
  name: lemlist Signal Agents API
  description: Signal Agents (watch lists) - create and configure watches, list the available signal types and filters, read
    detected signals, and push external signals.
  humanURL: https://developer.lemlist.com/api-reference/endpoints/watch-list/list-watch-lists
  baseURL: https://api.lemlist.com/api
  tags:
  - Signal Agents
  - Buying Signals
  properties:
  - type: OpenAPI
    url: openapi/lemlist-signal-agents-api-openapi.yml
- aid: lemlist:lemlist-webhooks-api
  name: lemlist Webhooks API
  description: Webhook subscription management - list, create with an optional shared secret, and delete. 76 event types are
    documented.
  humanURL: https://developer.lemlist.com/api-reference/endpoints/webhooks/add-webhook
  baseURL: https://api.lemlist.com/api
  tags:
  - Webhook
  tags_raw:
  - Webhooks
  properties:
  - type: OpenAPI
    url: openapi/lemlist-webhooks-api-openapi.yml
  - type: Webhooks
    url: asyncapi/lemlist-webhooks.yml
- aid: lemlist:lemlist-unsubscribes-api
  name: lemlist Unsubscribes API
  description: Suppression management - unsubscribe and re-subscribe contacts and variables, list and export the suppression
    set, and the legacy email/domain surface.
  humanURL: https://developer.lemlist.com/api-reference
  baseURL: https://api.lemlist.com/api
  tags:
  - Unsubscribes
  - Compliance
  properties:
  - type: OpenAPI
    url: openapi/lemlist-unsubscribes-api-openapi.yml
- aid: lemlist:lemlist-schedules-api
  name: lemlist Schedules API
  description: Sending schedules - CRUD and association with campaigns.
  humanURL: https://developer.lemlist.com/api-reference
  baseURL: https://api.lemlist.com/api
  tags:
  - Schedules
  properties:
  - type: OpenAPI
    url: openapi/lemlist-schedules-api-openapi.yml
- aid: lemlist:lemlist-tasks-api
  name: lemlist Tasks API
  description: Manual tasks - list, create, update and ignore.
  humanURL: https://developer.lemlist.com/api-reference
  baseURL: https://api.lemlist.com/api
  tags:
  - Task
  tags_raw:
  - Tasks
  properties:
  - type: OpenAPI
    url: openapi/lemlist-tasks-api-openapi.yml
- aid: lemlist:lemlist-activities-api
  name: lemlist Activities API
  description: The activity history feed, and deletion of call recordings and transcripts.
  humanURL: https://developer.lemlist.com/api-reference
  baseURL: https://api.lemlist.com/api
  tags:
  - Activities
  properties:
  - type: OpenAPI
    url: openapi/lemlist-activities-api-openapi.yml
- aid: lemlist:lemlist-team-api
  name: lemlist Team API
  description: Team-level endpoints - team information, senders, remaining credits and CRM users.
  humanURL: https://developer.lemlist.com/api-reference/endpoints/team/get-team
  baseURL: https://api.lemlist.com/api
  tags:
  - Team
  properties:
  - type: OpenAPI
    url: openapi/lemlist-team-api-openapi.yml
- aid: lemlist:lemlist-users-api
  name: lemlist Users API
  description: User endpoints - user detail and the connected channels available to the authenticated user.
  humanURL: https://developer.lemlist.com/api-reference/endpoints/users/get-user
  baseURL: https://api.lemlist.com/api
  tags:
  - User
  tags_raw:
  - Users
  properties:
  - type: OpenAPI
    url: openapi/lemlist-users-api-openapi.yml
- aid: lemlist:lemlist-email-accounts-api
  name: lemlist Email Accounts API
  description: Connect, test and disconnect custom SMTP/IMAP sending accounts.
  humanURL: https://developer.lemlist.com/api-reference/endpoints/email-accounts/connect-email-account
  baseURL: https://api.lemlist.com/api
  tags:
  - Email Accounts
  - Deliverability
  properties:
  - type: OpenAPI
    url: openapi/lemlist-email-accounts-api-openapi.yml
- aid: lemlist:lemlist-lemwarm-api
  name: lemlist lemwarm API
  description: lemwarm mailbox warm-up - start, pause, and read or update warm-up settings per mailbox.
  humanURL: https://developer.lemlist.com/api-reference
  baseURL: https://api.lemlist.com/api
  tags:
  - lemwarm
  - Deliverability
  properties:
  - type: OpenAPI
    url: openapi/lemlist-lemwarm-api-openapi.yml
- aid: lemlist:lemlist-deliverability-alerts-api
  name: lemlist Deliverability Alerts API
  description: Threshold alerts on deliverability metrics - create, read, update and delete.
  humanURL: https://developer.lemlist.com/api-reference
  baseURL: https://api.lemlist.com/api
  tags:
  - Deliverability alerts
  - Deliverability
  properties:
  - type: OpenAPI
    url: openapi/lemlist-deliverability-alerts-api-openapi.yml
- aid: lemlist:lemlist-fields-api
  name: lemlist Fields API
  description: The custom field definitions available on leads, contacts and companies.
  humanURL: https://developer.lemlist.com/api-reference
  baseURL: https://api.lemlist.com/api
  tags:
  - Fields
  properties:
  - type: OpenAPI
    url: openapi/lemlist-fields-api-openapi.yml
common:
- type: Website
  url: https://www.lemlist.com
- type: DeveloperPortal
  url: https://developer.lemlist.com
- type: Documentation
  url: https://developer.lemlist.com
- type: APIReference
  url: https://developer.lemlist.com/api-reference/getting-started/overview
- type: GettingStarted
  url: https://developer.lemlist.com/api-reference/getting-started/overview
- type: Support
  url: https://help.lemlist.com
- type: Blog
  url: https://www.lemlist.com/blog
- type: GitHubOrganization
  url: https://github.com/l3mpire
- type: Pricing
  url: https://www.lemlist.com/pricing
- type: SignUp
  url: https://app.lemlist.com/create-account
- type: Login
  url: https://app.lemlist.com/login
- type: TermsOfService
  url: https://www.lemlist.com/legal/terms
- type: PrivacyPolicy
  url: https://www.lemlist.com/legal/privacy-policy
- type: LinkedIn
  url: https://www.linkedin.com/company/lemlist
- type: Integrations
  url: https://www.lemlist.com/integrations
- type: Plans
  url: plans/lemlist-plans-pricing.yml
- type: RateLimits
  url: rate-limits/lemlist-rate-limits.yml
- type: Authentication
  url: authentication/lemlist-authentication.yml
- type: OAuthScopes
  url: scopes/lemlist-scopes.yml
- type: Conventions
  url: conventions/lemlist-conventions.yml
- type: ErrorCatalog
  url: errors/lemlist-problem-types.yml
- type: DataModel
  url: data-model/lemlist-data-model.yml
- type: Examples
  url: examples/lemlist-examples.yml
- type: Overlay
  url: overlays/lemlist-api-overlay.yaml
- type: Lifecycle
  url: lifecycle/lemlist-lifecycle.yml
- type: StatusPage
  url: https://status.lemlist.com
- type: Deprecation
  url: https://developer.lemlist.com/api-reference/getting-started/version
- type: Conformance
  url: conformance/lemlist-conformance.yml
- type: Compliance
  url: https://trust.lemlist.com/
- type: TrustCenter
  url: security/lemlist-trust-center.yml
- type: Security
  url: https://hackerone.com/lemlist
- type: VulnerabilityDisclosure
  url: security/lemlist-vulnerability-disclosure.yml
- type: DomainSecurity
  url: security/lemlist-domain-security.yml
- type: WellKnown
  url: well-known/lemlist-well-known.yml
- type: Webhooks
  url: asyncapi/lemlist-webhooks.yml
- type: MCPServer
  url: mcp/lemlist-mcp.yml
- type: AgentCard
  url: a2a/lemlist-a2a.yml
- type: AgentSkill
  url: skills/_index.yml
- type: AgenticAccess
  url: agentic-access/lemlist-agentic-access.yml
- type: Packages
  url: packages/lemlist-packages.yml
- type: SDKs
  url: packages/lemlist-packages.yml
- type: CLI
  url: cli/lemlist-cli.yml
- type: LLMsTxt
  url: llms/lemlist-llms.txt
- type: LlmsText
  url: https://developer.lemlist.com/llms.txt
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
x-enrichment:
  date: '2026-08-13'
  status: enriched
  artifacts_added: 22
  pass: local-v1

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