lemlist Sequences API
Campaign sequences, their steps, and A/B test variants on email steps.
OpenAPI Specification
openapi: 3.0.0
info:
title: lemlist Sequences API
version: 1.0.0
description: The Sequences operations of the lemlist API, split by tag from the OpenAPI lemlist publishes
at https://developer.lemlist.com/api-reference/openapi/v2.json. Operation content is carried verbatim
from the provider spec.
servers:
- url: https://api.lemlist.com/api
security:
- basicAuth: []
tags:
- name: Sequences
paths:
/campaigns/{campaignId}/sequences:
get:
summary: Get Campaign Sequences
tags:
- Sequences
parameters: []
responses:
'200':
headers:
Content-Type:
schema:
type: string
example: application/json
description: Success
content:
application/json:
schema:
type: object
description: Object where each key is a sequence ID and each value is a sequence object
additionalProperties:
type: object
properties:
_id:
type: string
description: The unique identifier of the sequence
steps:
type: array
description: Array of steps in the sequence
items:
type: object
properties:
_id:
type: string
description: The unique identifier of the step
delay:
type: integer
description: The delay in days before executing this step
emailTemplateId:
type: string
description: The unique identifier of the email template used for this step
type:
type: string
description: The type of step (e.g., email, linkedinSend, linkedinInvite,
conditional)
index:
type: integer
description: The position of the step in the sequence
sequenceId:
type: string
description: The unique identifier of the parent sequence
sequenceStep:
type: integer
description: The step number in the sequence
message:
type: string
description: The message content for the step (plain text for LinkedIn, HTML
for email)
subject:
type: string
description: The email subject line (only for email steps)
level:
type: integer
description: The nesting level of the sequence (0 for main sequence, 1+ for nested
conditional sequences)
parentId:
type: string
description: The unique identifier of the parent sequence (only for conditional
sequences)
conditionalStepIndex:
type: integer
description: The index of the conditional step that triggers this sequence (only
for conditional sequences)
example:
seq_rH5RD3fMkkt2gM3YC:
_id: seq_rH5RD3fMkkt2gM3YC
steps:
- _id: stp_sFUj6keaSz9wr049M
delay: 0
emailTemplateId: etp_ahlbc2yafFyu728H8
type: linkedinSend
index: 1
sequenceId: seq_rH5RD3fMkkt2gM3YC
sequenceStep: 0
message: "Hey {{firstName}}, \n\nwe're launching an event, a place where people can\
\ regularly meet, network, and learn from each other. We would love it if you could\
\ join us for a drink & chat next week. What do you say? \U0001F60A"
- _id: stp_qsTl0LO6zkQQJQqsP
delay: 1
emailTemplateId: etp_HFjUGtyDxIOxgZYcG
index: 2
sequenceId: seq_rH5RD3fMkkt2gM3YC
sequenceStep: 1
subject: '{{firstName}}, do we count on you for the event?'
message: '<p style="margin: 0px; box-sizing: border-box;">Hey {{firstName}},<br style="box-sizing:
border-box;"><br style="box-sizing: border-box;"></p>
<p style="margin: 0px; box-sizing: border-box;">Do you have any plans for Thursday,
7pm?<br style="box-sizing: border-box;"><br style="box-sizing: border-box;"></p>
<p style="margin: 0px; box-sizing: border-box;">What about spending the evening
with cool people by our office?<br style="box-sizing: border-box;"><br style="box-sizing:
border-box;"></p>
<p style="margin: 0px; box-sizing: border-box;">We''re launching an event, a place
where people can regularly meet, network, and build connections that help them grow
further 😊<br style="box-sizing: border-box;"><br style="box-sizing: border-box;"></p>
<p style="margin: 0px; box-sizing: border-box;">It would be really nice if we could
count on you for the event- <a target="_blank" style="color: rgb(0, 123, 255);
text-decoration: none; background-color: transparent; user-select: auto; box-sizing:
border-box;" rel="noopener noreferrer" href="{{event_link_to_send}}">here''s your
invite</a> 🔥</p><p style="margin: 0px; box-sizing: border-box;"><br style="box-sizing:
border-box;"></p>
<p style="margin: 0px; box-sizing: border-box;">Can you make it?<br style="box-sizing:
border-box;"><br style="box-sizing: border-box;"></p>
<p style="margin: 0px; box-sizing: border-box;">Sarah,</p><p style="margin: 0px;
box-sizing: border-box;">Head of Marketing</p>'
type: email
- _id: stp_pRcXzJDmOrBkFtNc3
delay: 1
emailTemplateId: etp_3tjFTgdOMS6JL8U1g
index: 3
sequenceId: seq_rH5RD3fMkkt2gM3YC
sequenceStep: 2
subject: '{{firstName}}, do we count on you for the event?'
message: '<p style="margin: 0px; box-sizing: border-box;">So, should I add you to
the list of attendees?<br style="box-sizing: border-box;"><br style="box-sizing:
border-box;"></p>
<p style="margin: 0px; box-sizing: border-box;">We''ll meet around 7pm, have a drink
and exchange with entrepreneurs, marketers, and salespeople.<br style="box-sizing:
border-box;"><br style="box-sizing: border-box;"></p>
<p style="margin: 0px; box-sizing: border-box;"><a target="_blank" style="color:
rgb(0, 123, 255); text-decoration: none; background-color: transparent; user-select:
auto; box-sizing: border-box;" rel="noopener noreferrer" href="{{event_link_to_send}}">Here''s
the link</a> if you want to join!<br style="box-sizing: border-box;"><br style="box-sizing:
border-box;"></p>
<p style="margin: 0px; box-sizing: border-box;">We would love to have you with us
for this event!<br style="box-sizing: border-box;"><br style="box-sizing: border-box;">Sarah</p><p
style="margin: 0px; box-sizing: border-box;">Head of Marketing</p>'
type: email
level: 0
'400':
description: 'Possible errors: Bad team / Campaign has no sequence'
content:
text/plain:
example: Bad team
'401':
description: The authentication you supplied is incorrect
content:
text/plain:
example: The authentication you supplied is incorrect
'404':
description: Campaign not found
content:
text/plain:
example: Campaign not found
'405':
description: Method not allowed
parameters:
- name: campaignId
in: path
required: true
description: The unique identifier of the campaign
example: cam_A1B2C3D4E5F6G7H8I9
schema:
type: string
/sequences/{sequenceId}/steps:
post:
summary: Add Step to Sequence
tags:
- Sequences
parameters: []
responses:
'200':
headers:
Content-Type:
schema:
type: string
example: application/json
description: Success
content:
application/json:
schema:
type: object
properties:
_id:
type: string
type:
type: string
delay:
type: integer
emailTemplateId:
type: string
message:
type: string
example:
_id: stp_V0JHmSpWiO0rxHUkz
type: linkedinInvite
delay: 2
emailTemplateId: etp_sw6csWaZNwnfdwGZ6
message: Hello, I would like...
'400':
description: 'Possible errors: Bad team / Error from createStep'
content:
text/plain:
example: Bad team
'401':
description: The authentication you supplied is incorrect
content:
text/plain:
example: The authentication you supplied is incorrect
'405':
description: Method not allowed
requestBody:
content:
application/json:
schema:
type: object
properties:
type:
type: string
description: The type of step to create
enum:
- email
- manual
- phone
- api
- linkedinVisit
- linkedinInvite
- linkedinSend
- linkedinVoiceNote
- linkedinFollow
- linkedinLikeLastPost
- linkedinCommentLastPost
- linkedinEndorse
- linkedinWithdrawInvitation
- sendToAnotherCampaign
- conditional
- whatsappMessage
- sms
index:
type: integer
description: The position within the sequence to insert the new step (≥ -1). If omitted
or greater than the number of steps, the new step is added to the end
delay:
type: integer
description: Delay in days before executing this step. Defaults to 0 for the first step
and 1 for subsequent steps
subject:
type: string
description: Email subject line (required for email steps)
message:
type: string
description: Content of the email or message (used for email, linkedinInvite, linkedinSend,
manual, phone, whatsappMessage, sms steps). Required for linkedinSend, whatsappMessage,
and sms
altMessage:
type: string
description: Alternate message for linkedinSend steps
title:
type: string
description: Title or label for manual steps
method:
type: string
description: HTTP method for API steps
enum:
- GET
- POST
- PUT
- DELETE
- PATCH
url:
type: string
description: URL of the API endpoint to call (required for api steps). Must start with
http:// or https://
conditionKey:
type: string
description: Condition key for conditional steps
enum:
- hasEmailAddress
- hasLinkedinUrl
- hasPhoneNumber
- hasScore
- emailsOpened
- emailsClicked
- emailsUnsubscribed
- meetingBooked
- linkedinInviteAccepted
- linkedinOpened
- aircallDone
- linkedinNetworkCheck
- hasWhatsappAccount
delayType:
type: string
description: Delay type for conditional steps
enum:
- within
- waitUntil
campaignId:
type: string
description: Target campaign ID for sendToAnotherCampaign steps. The campaign must exist
and not be archived
images:
type: array
items:
type: string
format: uri
description: 'Public HTTPS URLs of images to attach to a `linkedinInvite` or `linkedinSend`
step. lemlist downloads each file and re-hosts it. Allowed MIME types: `image/png`,
`image/jpeg`, `image/gif`. Up to 20 MB per file, and up to 6 items total combined
with `videos`.'
videos:
type: array
items:
type: string
format: uri
description: 'Public HTTPS URLs of videos to attach to a `linkedinInvite` or `linkedinSend`
step. lemlist downloads each file and re-hosts it. Allowed MIME types: `video/mp4`,
`video/quicktime`. Up to 20 MB per file, and up to 6 items total combined with `images`.'
skillName:
type: string
description: Name of the LinkedIn skill to endorse on the lead's profile. Applies to
`linkedinEndorse` steps only.
endorseAnyFallback:
type: boolean
description: Applies to `linkedinEndorse` steps only. When `true` and the named skill
is not on the lead's profile, lemlist falls back to endorsing any available skill.
recordMode:
type: string
description: Applies to `linkedinVoiceNote` steps only. Determines how the audio is
sourced. `manual` (default) means the user records the audio themselves from the lemlist
UI after step creation; `ai` means lemlist generates the audio from a text template
provided in the lemlist UI.
enum:
- manual
- ai
examples:
Email Step:
value:
type: email
subject: '{{firstName}}, quick question about {{companyName}}'
message: <p>Hi {{firstName}},</p><p>I noticed {{companyName}} is working on improving
customer engagement. Would you be interested in discussing how we can help?</p><p>Best
regards,<br>{{senderName}}</p>
delay: 1
index: 2
LinkedIn Invite:
value:
type: linkedinInvite
message: Hi {{firstName}}, I'd love to connect and learn more about your work at {{companyName}}!
delay: 0
LinkedIn Send:
value:
type: linkedinSend
message: Hey {{firstName}}, thanks for connecting! I wanted to reach out about...
delay: 2
LinkedIn Send with Media:
value:
type: linkedinSend
message: Hey {{firstName}}, sharing a quick overview of what we're building.
images:
- https://example.com/assets/overview.png
videos:
- https://example.com/assets/demo.mp4
delay: 2
Manual Task:
value:
type: manual
title: Call prospect
message: Discuss their pain points and schedule a demo
delay: 1
Phone Call:
value:
type: phone
message: Follow up on the email sent yesterday
delay: 1
API Call:
value:
type: api
method: POST
url: https://api.example.com/webhook
delay: 0
LinkedIn Visit:
value:
type: linkedinVisit
delay: 0
Conditional Step:
value:
type: conditional
conditionKey: linkedinInviteAccepted
delayType: waitUntil
delay: 1
Send to Another Campaign:
value:
type: sendToAnotherCampaign
campaignId: cam_ABC123XYZ456
delay: 0
WhatsApp Message:
value:
type: whatsappMessage
message: Hi {{firstName}}, following up on our conversation...
delay: 1
parameters:
- name: sequenceId
in: path
required: true
description: The unique identifier of the sequence
example: seq_lkCSKd32qSZZTe5Ru
schema:
type: string
/sequences/{sequenceId}/steps/{stepId}:
patch:
summary: Update Sequence Step
tags:
- Sequences
parameters: []
responses:
'200':
headers:
Content-Type:
schema:
type: string
example: application/json
description: Success
content:
application/json:
schema:
type: object
properties:
_id:
type: string
type:
type: string
delay:
type: integer
emailTemplateId:
type: string
message:
type: string
example:
_id: stp_V0JHmSpWiO0rxHUkz
type: linkedinInvite
delay: 0
emailTemplateId: etp_HZvLoLNEwdJ8Vu0w7
message: Hello, I want to...
'400':
description: 'Possible errors: Bad team / Error from updateStep'
content:
text/plain:
example: Bad team
'401':
description: The authentication you supplied is incorrect
content:
text/plain:
example: The authentication you supplied is incorrect
'405':
description: Method not allowed
requestBody:
content:
application/json:
schema:
type: object
required:
- type
properties:
type:
type: string
description: The type of step (required but cannot be changed - must match the existing
step type)
enum:
- email
- manual
- phone
- api
- linkedinVisit
- linkedinInvite
- linkedinSend
- linkedinVoiceNote
- linkedinFollow
- linkedinLikeLastPost
- linkedinCommentLastPost
- linkedinEndorse
- linkedinWithdrawInvitation
- sendToAnotherCampaign
- conditional
- whatsappMessage
- sms
delay:
type: integer
description: Delay in days before executing this step
subject:
type: string
description: Email subject line (for email steps)
message:
type: string
description: Content of the email or message (for email, linkedinInvite, linkedinSend,
manual, phone, whatsappMessage, sms steps)
altMessage:
type: string
description: Alternate message for linkedinSend steps
title:
type: string
description: Title or label for manual steps
method:
type: string
description: HTTP method for API steps
enum:
- GET
- POST
- PUT
- DELETE
- PATCH
url:
type: string
description: URL of the API endpoint to call (for api steps). Must start with http://
or https://
conditionKey:
type: string
description: Condition key for conditional steps
enum:
- hasEmailAddress
- hasLinkedinUrl
- hasPhoneNumber
- hasScore
- emailsOpened
- emailsClicked
- emailsUnsubscribed
- meetingBooked
- linkedinInviteAccepted
- linkedinOpened
- aircallDone
- linkedinNetworkCheck
- hasWhatsappAccount
delayType:
type: string
description: Delay type for conditional steps
enum:
- within
- waitUntil
campaignId:
type: string
description: Target campaign ID for sendToAnotherCampaign steps. The campaign must exist
and not be archived
images:
type: array
items:
type: string
format: uri
description: 'Public HTTPS URLs of images to attach to a `linkedinInvite` or `linkedinSend`
step. Replaces the step''s current images — pass an empty array to clear them. Allowed
MIME types: `image/png`, `image/jpeg`, `image/gif`. Up to 20 MB per file, and up to
6 items total combined with `videos`.'
videos:
type: array
items:
type: string
format: uri
description: 'Public HTTPS URLs of videos to attach to a `linkedinInvite` or `linkedinSend`
step. Replaces the step''s current videos — pass an empty array to clear them. Allowed
MIME types: `video/mp4`, `video/quicktime`. Up to 20 MB per file, and up to 6 items
total combined with `images`.'
skillName:
type: string
description: Name of the LinkedIn skill to endorse on the lead's profile. Applies to
`linkedinEndorse` steps only.
endorseAnyFallback:
type: boolean
description: Applies to `linkedinEndorse` steps only. When `true` and the named skill
is not on the lead's profile, lemlist falls back to endorsing any available skill.
recordMode:
type: string
description: Applies to `linkedinVoiceNote` steps only. Determines how the audio is
sourced. `manual` (default) means the user records the audio themselves from the lemlist
UI after step creation; `ai` means lemlist generates the audio from a text template
provided in the lemlist UI.
enum:
- manual
- ai
examples:
Update Email Step:
value:
type: email
subject: '{{firstName}}, following up on our conversation'
message: <p>Hi {{firstName}},</p><p>Just wanted to circle back on our previous email.
Have you had a chance to review it?</p><p>Best,<br>{{senderName}}</p>
delay: 2
Update LinkedIn Invite:
value:
type: linkedinInvite
message: Hi {{firstName}}, I'd love to connect with you to discuss potential collaboration
opportunities!
delay: 0
Update LinkedIn Send:
value:
type: linkedinSend
message: Thanks for accepting my invite, {{firstName}}! I wanted to reach out about...
altMessage: Alternative message if the main one fails
delay: 3
Update LinkedIn Send Media:
value:
type: linkedinSend
images:
- https://example.com/assets/overview.png
videos: []
Update Manual Task:
value:
type: manual
title: Schedule follow-up call
message: Discuss pain points and propose next steps
delay: 2
Update Phone Call:
value:
type: phone
message: Call to discuss the proposal sent via email
delay: 1
Update API Call:
value:
type: api
method: PUT
url: https://api.example.com/webhook/update
delay: 0
Update LinkedIn Visit:
value:
type: linkedinVisit
delay: 1
Update Conditional Step:
value:
type: conditional
conditionKey: emailsOpened
delayType: within
delay: 3
Update Send to Another Campaign:
value:
type: sendToAnotherCampaign
campaignId: cam_XYZ789ABC123
Update WhatsApp Message:
value:
type: whatsappMessage
message: Hi {{firstName}}, just checking in to see if you received my previous messages.
delay: 2
parameters:
- name: sequenceId
in: path
required: true
description: The unique identifier of the sequence
example: seq_lkCSKd32qSZZTe5Ru
schema:
type: string
- name: stepId
in: path
required: true
description: The unique identifier of the step
example: stp_V0JHmSpWiO0rxHUkz
schema:
type: string
delete:
summary: Delete Sequence Step
tags:
- Sequences
parameters: []
responses:
'200':
headers:
Content-Type:
schema:
type: string
example: application/json
description: Success
content:
application/json:
schema:
type: object
properties:
ok:
type: boolean
example:
ok: true
'400':
description: 'Possible errors: Bad team / You cannot delete this step because the campaign is
running'
content:
text/plain:
example: Bad team
'401':
description: The authentication you supplied is incorrect
content:
text/plain:
example: The authentication you supplied is incorrect
'404':
description: 'Possible errors: Sequence not found / Step not found'
content:
text/plain:
example: Sequence not found
'405':
description: Method not allowed
/sequences/{sequenceId}/steps/{stepId}/ab-test:
post:
summary: Create A/B Test Variant
tags:
- Sequences
description: Creates variant B of an A/B test on an email step, prefilled from variant A, and starts
the test (leads are split between A and B). Requires the Email Pro plan.
parameters: []
responses:
'200':
description: Variant B created
content:
application/json:
schema:
type: object
properties:
stepId:
type: string
abTest:
oneOf:
- type: boolean
- type: string
enum:
- A
- B
emailTemplateBId:
type: string
description: Email template ID of variant B
subject:
type: string
description: Variant B email subject
message:
type: string
description: Variant B email body (HTML)
altMessage:
type: string
cc:
type: array
items:
type: string
plainText:
type: boolean
example:
stepId: stp_V0JHmSpWiO0rxHUkz
abTest: true
emailTemplateBId: etp_9aZ2k1QwErTyUiOp3
subject: Quick question, {{firstName}}
message: <div>Hi {{firstName}}, ...</div>
'400':
description: Bad request (e.g. step is not an email step, has no template, already runs an A/B
test, or the campaign is running)
content:
text/plain:
example: A/B test already exists on this step
'401':
description: The authentication you supplied is incorrect
content:
text/plain:
example: The authentication you supplied is incorrect
'402':
description: A/B testing requires at least the Email Pro plan
content:
text/plain:
example: route is available starting emailPro plan
'404':
description: Sequence, step, or A/B test variant not found
content:
text/plain:
example: No A/B test variant on this step
'405':
description: Method not allowed
parameters:
- name: sequenceId
in: path
required: true
description: The unique identifier of the sequence
example: seq_lkCSKd32qSZZTe5Ru
schema:
type: string
- name: stepId
in: path
required: true
description: The unique identifier of the step
example: stp_V0JHmSpWiO0rxHUkz
schema:
type: string
get:
summary: Get A/B Test Variant
tags:
- Sequences
description: Returns variant B (subject, message, config) of the A/B test on an email step. Requires
the Email Pro plan.
parameters: []
responses:
'200':
des
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