Klaviyo

Klaviyo Segments API

segments

GitHub OpenAPI
Business capability
Customer Segmentation Management BC-420.20

Operations 11

Each operation below carries the questions people ask an LLM about it and the instructions they give an agent to run it. Generated by API Evangelist overlay

GET /api/segments List segments in the account · Get Segments #
Ask an LLM
“What audience segments have I built in Klaviyo?”
“Can I filter segments by name or when they were created?”
Tell an agent
List all my segments.
Find segments matching {filter}.
POST /api/segments Create a segment · Create Segment #
Ask an LLM
“How do I build a new audience segment from a set of conditions?”
“What do I pass to define a segment's rules?”
Tell an agent
Create a segment with this definition: {segment}.
Build a new segment of customers matching {segment}.
GET /api/segments/{id} Get one segment by ID · Get Segment #
Ask an LLM
“How many profiles are in a particular segment?”
“Can I see a segment's definition by its ID?”
Tell an agent
Get segment {segment_id}.
Show segment {segment_id} with {additional_fields}.
PATCH /api/segments/{id} Update a segment's name or rules · Update Segment #
Ask an LLM
“Can I change the conditions of an existing segment?”
“What's the way to rename a segment?”
Tell an agent
Update segment {segment_id} with {changes}.
Change the conditions of segment {segment_id} to {changes}.
DELETE /api/segments/{id} Delete a segment · Delete Segment #
Ask an LLM
“How do I remove a segment I don't need anymore?”
“Can I delete a segment by its ID?”
Tell an agent destructive · confirm first
Delete segment {segment_id}.
Remove the unused segment {segment_id}.
GET /api/segments/{id}/tags List a segment's tags · Get Tags for Segment #
Ask an LLM
“What tags are on a particular segment?”
“Can I get full tag records for one segment?”
Tell an agent
List the tags on segment {segment_id}.
Show full tag details for segment {segment_id}.
GET /api/segments/{id}/relationships/tags Get tag IDs for a segment · Get Tag IDs for Segment #
Ask an LLM
“Can I fetch only the tag IDs on a segment?”
“What tag relationships does a segment have?”
Tell an agent
Get just the tag IDs for segment {segment_id}.
Return tag relationships of segment {segment_id}.
GET /api/segments/{id}/profiles List the profiles in a segment · Get Profiles for Segment #
Ask an LLM
“Who is currently in a given segment?”
“Can I filter a segment's members by email or the date they joined?”
Tell an agent
List the profiles in segment {segment_id}.
Show members of segment {segment_id} matching {filter}.
GET /api/segments/{id}/relationships/profiles Get profile IDs in a segment · Get Profile IDs for Segment #
Ask an LLM
“Can I get only the profile IDs of a segment's members?”
“What's the lightweight way to export membership IDs for a segment?”
Tell an agent
Get just the profile IDs in segment {segment_id}.
Return profile relationships of segment {segment_id}.
GET /api/segments/{id}/flow-triggers List flows triggered by a segment · Get Flows Triggered by Segment #
Ask an LLM
“Which flows start when someone joins a given segment?”
“Can I see full flow records for automations a segment triggers?”
Tell an agent
List flows triggered by segment {segment_id}.
Show full flow details for automations started by segment {segment_id}.
GET /api/segments/{id}/relationships/flow-triggers Get IDs of flows a segment triggers · Get IDs for Flows Triggered by Segment #
Ask an LLM
“Can I get only the flow IDs that use a segment as their trigger?”
“What flow-trigger relationships does a segment have?”
Tell an agent
Get just the flow IDs triggered by segment {segment_id}.
Return flow-trigger relationships of segment {segment_id}.

Documentation

📖
Documentation
https://developers.klaviyo.com/
📖
Authentication
https://developers.klaviyo.com/en/docs/authenticate_
📖
RateLimits
https://developers.klaviyo.com/en/docs/rate_limits_and_error_handling

Specifications

⚙
OpenAPI
https://raw.githubusercontent.com/api-evangelist/klaviyo/refs/heads/main/openapi/klaviyo-segments-api-openapi.yml
⚙
AsyncAPI
https://raw.githubusercontent.com/api-evangelist/klaviyo/refs/heads/main/asyncapi/klaviyo-webhooks-asyncapi.yaml

Other Resources

🔗
Reference
https://developers.klaviyo.com/en/reference/api_overview
🔗
Versioning
https://developers.klaviyo.com/en/docs/api_versioning_and_deprecation_policy
🔗
ChangeLog
https://developers.klaviyo.com/en/docs/changelog_
🔗
SDKs
https://developers.klaviyo.com/en/docs/sdk_overview
🔗
GitHub
https://github.com/klaviyo/openapi
🔗
Overlay
https://raw.githubusercontent.com/api-evangelist/klaviyo/refs/heads/main/overlays/klaviyo-segments-api-overlay.yaml

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OpenAPI Specification

klaviyo-segments-api-openapi.yml Raw ↑ 
openapi: 3.2.0
info:
  title: Klaviyo Segments API
  version: '2026-04-15'
  description: The Klaviyo REST API. Please visit https://developers.klaviyo.com for more details.
  contact:
    name: Klaviyo Developer Experience Team
    email: developers@klaviyo.com
    url: https://developers.klaviyo.com
  termsOfService: https://www.klaviyo.com/legal/api-terms
  license:
    name: License
    url: https://www.klaviyo.com/legal
servers:
- url: https://a.klaviyo.com
  description: Production
security:
- Klaviyo-API-Key: []
tags:


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# Full source: https://raw.githubusercontent.com/api-evangelist/klaviyo/refs/heads/main/openapi/klaviyo-segments-api-openapi.yml