Kit

Kit

Access the Kit (formerly ConvertKit) API with managed OAuth authentication. Manage subscribers, tags, forms, sequences, broadcasts, custom fields, and webhooks.

Quick Start

# List subscribers
python <<'EOF'
import urllib.request, os, json
req = urllib.request.Request('https://gateway.maton.ai/kit/v4/subscribers?per_page=10')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

Base URL

https://gateway.maton.ai/kit/{native-api-path}

Replace {native-api-path} with the actual Kit API endpoint path. The gateway proxies requests to api.kit.com and automatically injects your OAuth token.

Authentication

All requests require the Maton API key in the Authorization header:

Authorization: Bearer $MATON_API_KEY

Environment Variable: Set your API key as MATON_API_KEY:

export MATON_API_KEY="YOUR_API_KEY"

Getting Your API Key

1. Sign in or create an account at maton.ai
2. Go to maton.ai/settings
3. Copy your API key

Connection Management

Manage your Kit OAuth connections at https://ctrl.maton.ai.

List Connections

python <<'EOF'
import urllib.request, os, json
req = urllib.request.Request('https://ctrl.maton.ai/connections?app=kit&status=ACTIVE')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

Create Connection

python <<'EOF'
import urllib.request, os, json
data = json.dumps({'app': 'kit'}).encode()
req = urllib.request.Request('https://ctrl.maton.ai/connections', data=data, method='POST')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
req.add_header('Content-Type', 'application/json')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

Get Connection

python <<'EOF'
import urllib.request, os, json
req = urllib.request.Request('https://ctrl.maton.ai/connections/{connection_id}')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

Response:

{
  "connection": {
    "connection_id": "cb2025b3-706f-4b5d-87a5-c6809c0c7ec4",
    "status": "ACTIVE",
    "creation_time": "2026-02-07T00:04:08.476727Z",
    "last_updated_time": "2026-02-07T00:05:58.001964Z",
    "url": "https://connect.maton.ai/?session_token=...",
    "app": "kit",
    "metadata": {}
  }
}

Open the returned url in a browser to complete OAuth authorization.

Delete Connection

python <<'EOF'
import urllib.request, os, json
req = urllib.request.Request('https://ctrl.maton.ai/connections/{connection_id}', method='DELETE')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

Specifying Connection

If you have multiple Kit connections, specify which one to use with the Maton-Connection header:

python <<'EOF'
import urllib.request, os, json
req = urllib.request.Request('https://gateway.maton.ai/kit/v4/subscribers')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
req.add_header('Maton-Connection', 'cb2025b3-706f-4b5d-87a5-c6809c0c7ec4')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

If omitted, the gateway uses the default (oldest) active connection.

API Reference

Subscribers

List Subscribers

GET /kit/v4/subscribers

Query parameters:

• per_page - Results per page (default: 500, max: 1000)
• after - Cursor for next page
• before - Cursor for previous page
• status - Filter by: active, inactive, bounced, complained, cancelled, or all
• email_address - Filter by specific email
• created_after / created_before - Filter by creation date (yyyy-mm-dd)
• updated_after / updated_before - Filter by update date (yyyy-mm-dd)
• include_total_count - Include total count (slower)

Response:

{
  "subscribers": [
    {
      "id": 3914682852,
      "first_name": "Test User",
      "email_address": "test@example.com",
      "state": "active",
      "created_at": "2026-02-07T00:42:54Z",
      "fields": {"company": null}
    }
  ],
  "pagination": {
    "has_previous_page": false,
    "has_next_page": false,
    "start_cursor": "WzE0OV0=",
    "end_cursor": "WzE0OV0=",
    "per_page": 500
  }
}

Get Subscriber

GET /kit/v4/subscribers/{id}

Create Subscriber

POST /kit/v4/subscribers
Content-Type: application/json

{
  "email_address": "user@example.com",
  "first_name": "John"
}

Update Subscriber

PUT /kit/v4/subscribers/{id}
Content-Type: application/json

{
  "first_name": "Updated Name"
}

Tags

List Tags

GET /kit/v4/tags

Query parameters: per_page, after, before, include_total_count

Create Tag

POST /kit/v4/tags
Content-Type: application/json

{
  "name": "new-tag"
}

Response:

{
  "tag": {
    "id": 15690016,
    "name": "new-tag",
    "created_at": "2026-02-07T00:42:53Z"
  }
}

Update Tag

PUT /kit/v4/tags/{id}
Content-Type: application/json

{
  "name": "updated-tag-name"
}

Delete Tag

DELETE /kit/v4/tags/{id}

Returns 204 No Content on success.

Tag a Subscriber

POST /kit/v4/tags/{tag_id}/subscribers
Content-Type: application/json

{
  "email_address": "user@example.com"
}

Remove Tag from Subscriber

DELETE /kit/v4/tags/{tag_id}/subscribers/{subscriber_id}

Returns 204 No Content on success.

List Subscribers with Tag

GET /kit/v4/tags/{tag_id}/subscribers

Forms

List Forms

GET /kit/v4/forms

Query parameters:

• per_page, after, before, include_total_count
• status - Filter by: active, archived, trashed, or all
• type - embed for embedded forms, hosted for landing pages

Response:

{
  "forms": [
    {
      "id": 9061198,
      "name": "Creator Profile",
      "created_at": "2026-02-07T00:00:32Z",
      "type": "embed",
      "format": null,
      "embed_js": "https://chris-kim-2.kit.com/c682763b07/index.js",
      "embed_url": "https://chris-kim-2.kit.com/c682763b07",
      "archived": false,
      "uid": "c682763b07"
    }
  ],
  "pagination": {...}
}

Add Subscriber to Form

POST /kit/v4/forms/{form_id}/subscribers
Content-Type: application/json

{
  "email_address": "user@example.com"
}

List Form Subscribers

GET /kit/v4/forms/{form_id}/subscribers

Sequences

List Sequences

GET /kit/v4/sequences

Response:

{
  "sequences": [
    {
      "id": 123,
      "name": "Welcome Sequence",
      "hold": false,
      "repeat": false,
      "created_at": "2026-01-01T00:00:00Z"
    }
  ],
  "pagination": {...}
}

Add Subscriber to Sequence

POST /kit/v4/sequences/{sequence_id}/subscribers
Content-Type: application/json

{
  "email_address": "user@example.com"
}

List Sequence Subscribers

GET /kit/v4/sequences/{sequence_id}/subscribers

Broadcasts

List Broadcasts

GET /kit/v4/broadcasts

Query parameters: per_page, after, before, include_total_count

Response:

{
  "broadcasts": [
    {
      "id": 123,
      "publication_id": 456,
      "created_at": "2026-02-07T00:00:00Z",
      "subject": "My Broadcast",
      "preview_text": "Preview...",
      "content": "<p>Content</p>",
      "public": false,
      "published_at": null,
      "send_at": null,
      "email_template": {"id": 123, "name": "Text only"}
    }
  ],
  "pagination": {...}
}

Segments

List Segments

GET /kit/v4/segments

Query parameters: per_page, after, before, include_total_count

Custom Fields

List Custom Fields

GET /kit/v4/custom_fields

Response:

{
  "custom_fields": [
    {
      "id": 1192946,
      "name": "ck_field_1192946_company",
      "key": "company",
      "label": "Company"
    }
  ],
  "pagination": {...}
}

Create Custom Field

POST /kit/v4/custom_fields
Content-Type: application/json

{
  "label": "Company"
}

Update Custom Field

PUT /kit/v4/custom_fields/{id}
Content-Type: application/json

{
  "label": "Company Name"
}

Delete Custom Field

DELETE /kit/v4/custom_fields/{id}

Returns 204 No Content on success.

Purchases

List Purchases

GET /kit/v4/purchases

Query parameters: per_page, after, before, include_total_count

Email Templates

List Email Templates

GET /kit/v4/email_templates

Response:

{
  "email_templates": [
    {
      "id": 4956167,
      "name": "Text only",
      "is_default": true,
      "category": "Classic"
    }
  ],
  "pagination": {...}
}

Webhooks

List Webhooks

GET /kit/v4/webhooks

Create Webhook

POST /kit/v4/webhooks
Content-Type: application/json

{
  "target_url": "https://example.com/webhook",
  "event": {"name": "subscriber.subscriber_activate"}
}

Response:

{
  "webhook": {
    "id": 5291560,
    "account_id": 2596262,
    "event": {
      "name": "subscriber_activate",
      "initiator_value": null
    },
    "target_url": "https://example.com/webhook"
  }
}

Delete Webhook

DELETE /kit/v4/webhooks/{id}

Returns 204 No Content on success.

Pagination

Kit uses cursor-based pagination. Use after and before query parameters with cursor values from the response.

GET /kit/v4/subscribers?per_page=100&after=WzE0OV0=

Response includes pagination info:

{
  "subscribers": [...],
  "pagination": {
    "has_previous_page": false,
    "has_next_page": true,
    "start_cursor": "WzE0OV0=",
    "end_cursor": "WzI0OV0=",
    "per_page": 100
  }
}

Code Examples

JavaScript

const response = await fetch(
  'https://gateway.maton.ai/kit/v4/subscribers?per_page=10',
  {
    headers: {
      'Authorization': `Bearer ${process.env.MATON_API_KEY}`
    }
  }
);
const data = await response.json();

Python

import os
import requests

response = requests.get(
    'https://gateway.maton.ai/kit/v4/subscribers',
    headers={'Authorization': f'Bearer {os.environ["MATON_API_KEY"]}'},
    params={'per_page': 10}
)
data = response.json()

Notes

• Kit API uses V4 (V3 is deprecated)
• Subscriber IDs are integers
• Custom field keys are auto-generated from labels
• Bulk operations (>100 items) are processed asynchronously
• Delete operations return 204 No Content with empty body
• IMPORTANT: When using curl commands, use curl -g when URLs contain brackets to disable glob parsing
• IMPORTANT: When piping curl output to jq or other commands, environment variables like $MATON_API_KEY may not expand correctly in some shell environments

Error Handling

Troubleshooting: Invalid API Key

When you receive a "Invalid API key" error, ALWAYS follow these steps before concluding there is an issue:

1. Check that the MATON_API_KEY environment variable is set:

echo $MATON_API_KEY

2. Verify the API key is valid by listing connections:

python <<'EOF'
import urllib.request, os, json
req = urllib.request.Request('https://ctrl.maton.ai/connections')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

Resources

• Kit API Overview
• Kit API Subscribers
• Kit API Tags
• Kit API Forms