Mailchimp

Mailchimp

Access the Mailchimp Marketing API with managed OAuth authentication. Manage audiences, campaigns, templates, automations, reports, and subscribers for email marketing.

Quick Start

# List all audiences
python <<'EOF'
import urllib.request, os, json
req = urllib.request.Request('https://gateway.maton.ai/mailchimp/3.0/lists')
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/mailchimp/{native-api-path}

Replace {native-api-path} with the actual Mailchimp API endpoint path (e.g., 3.0/lists). The gateway proxies requests to your Mailchimp data center 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 Mailchimp 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=mailchimp&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': 'mailchimp'}).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": "21fd90f9-5935-43cd-b6c8-bde9d915ca80",
    "status": "ACTIVE",
    "creation_time": "2025-12-08T07:20:53.488460Z",
    "last_updated_time": "2026-01-31T20:03:32.593153Z",
    "url": "https://connect.maton.ai/?session_token=...",
    "app": "mailchimp",
    "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 Mailchimp 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/mailchimp/3.0/lists')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
req.add_header('Maton-Connection', '21fd90f9-5935-43cd-b6c8-bde9d915ca80')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

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

API Reference

Lists (Audiences)

Within the Mailchimp app, "audience" is the common term, but the API uses "lists" for endpoints.

Get All Lists

GET /mailchimp/3.0/lists

Query parameters:

• count - Number of records to return (default 10, max 1000)
• offset - Number of records to skip (for pagination)
• fields - Comma-separated list of fields to include
• exclude_fields - Comma-separated list of fields to exclude

Example:

python <<'EOF'
import urllib.request, os, json
req = urllib.request.Request('https://gateway.maton.ai/mailchimp/3.0/lists?count=10')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

Response:

{
  "lists": [
    {
      "id": "abc123def4",
      "name": "Newsletter Subscribers",
      "contact": {
        "company": "Acme Corp",
        "address1": "123 Main St"
      },
      "stats": {
        "member_count": 5000,
        "unsubscribe_count": 100,
        "open_rate": 0.25
      }
    }
  ],
  "total_items": 1
}

Get a List

GET /mailchimp/3.0/lists/{list_id}

Example:

python <<'EOF'
import urllib.request, os, json
req = urllib.request.Request('https://gateway.maton.ai/mailchimp/3.0/lists/abc123def4')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

Create a List

POST /mailchimp/3.0/lists
Content-Type: application/json

{
  "name": "Newsletter",
  "contact": {
    "company": "Acme Corp",
    "address1": "123 Main St",
    "city": "New York",
    "state": "NY",
    "zip": "10001",
    "country": "US"
  },
  "permission_reminder": "You signed up for our newsletter",
  "campaign_defaults": {
    "from_name": "Acme Corp",
    "from_email": "newsletter@acme.com",
    "subject": "",
    "language": "en"
  },
  "email_type_option": true
}

Update a List

PATCH /mailchimp/3.0/lists/{list_id}

Delete a List

DELETE /mailchimp/3.0/lists/{list_id}

List Members (Subscribers)

Members are contacts within an audience. The API uses MD5 hash of the lowercase email address as the subscriber identifier.

Get List Members

GET /mailchimp/3.0/lists/{list_id}/members

Query parameters:

• status - Filter by subscription status (subscribed, unsubscribed, cleaned, pending, transactional)
• count - Number of records to return
• offset - Number of records to skip

Example:

python <<'EOF'
import urllib.request, os, json
req = urllib.request.Request('https://gateway.maton.ai/mailchimp/3.0/lists/abc123def4/members?status=subscribed&count=50')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

Response:

{
  "members": [
    {
      "id": "f4b7c8d9e0",
      "email_address": "john@example.com",
      "status": "subscribed",
      "merge_fields": {
        "FNAME": "John",
        "LNAME": "Doe"
      },
      "tags": [
        {"id": 1, "name": "VIP"}
      ]
    }
  ],
  "total_items": 500
}

Get a Member

GET /mailchimp/3.0/lists/{list_id}/members/{subscriber_hash}

The subscriber_hash is the MD5 hash of the lowercase email address.

Example:

# For email "john@example.com", subscriber_hash = md5("john@example.com")
python <<'EOF'
import urllib.request, os, json
req = urllib.request.Request('https://gateway.maton.ai/mailchimp/3.0/lists/abc123def4/members/b4c9a0d1e2f3g4h5')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

Add a Member

POST /mailchimp/3.0/lists/{list_id}/members
Content-Type: application/json

{
  "email_address": "newuser@example.com",
  "status": "subscribed",
  "merge_fields": {
    "FNAME": "Jane",
    "LNAME": "Smith"
  },
  "tags": ["Newsletter", "Premium"]
}

Example:

python <<'EOF'
import urllib.request, os, json
data = json.dumps({'email_address': 'newuser@example.com', 'status': 'subscribed', 'merge_fields': {'FNAME': 'Jane', 'LNAME': 'Smith'}}).encode()
req = urllib.request.Request('https://gateway.maton.ai/mailchimp/3.0/lists/abc123def4/members', 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

Update a Member

PATCH /mailchimp/3.0/lists/{list_id}/members/{subscriber_hash}

Example:

python <<'EOF'
import urllib.request, os, json
data = json.dumps({'merge_fields': {'FNAME': 'Jane', 'LNAME': 'Doe'}}).encode()
req = urllib.request.Request('https://gateway.maton.ai/mailchimp/3.0/lists/abc123def4/members/b4c9a0d1e2f3g4h5', data=data, method='PATCH')
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

Add or Update a Member (Upsert)

PUT /mailchimp/3.0/lists/{list_id}/members/{subscriber_hash}
Content-Type: application/json

{
  "email_address": "user@example.com",
  "status_if_new": "subscribed",
  "merge_fields": {
    "FNAME": "Jane",
    "LNAME": "Smith"
  }
}

Creates a new member or updates an existing one based on the email hash. Use status_if_new to set the status when creating a new member.

Delete a Member

Archives a member (can be re-added later):

DELETE /mailchimp/3.0/lists/{list_id}/members/{subscriber_hash}

Returns 204 No Content on success.

To permanently delete (GDPR compliant):

POST /mailchimp/3.0/lists/{list_id}/members/{subscriber_hash}/actions/delete-permanent

Member Tags

Get Member Tags

GET /mailchimp/3.0/lists/{list_id}/members/{subscriber_hash}/tags

Add or Remove Tags

POST /mailchimp/3.0/lists/{list_id}/members/{subscriber_hash}/tags
Content-Type: application/json

{
  "tags": [
    {"name": "VIP", "status": "active"},
    {"name": "Old Tag", "status": "inactive"}
  ]
}

Returns 204 No Content on success.

Segments

Get Segments

GET /mailchimp/3.0/lists/{list_id}/segments

Example:

python <<'EOF'
import urllib.request, os, json
req = urllib.request.Request('https://gateway.maton.ai/mailchimp/3.0/lists/abc123def4/segments')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

Create a Segment

POST /mailchimp/3.0/lists/{list_id}/segments
Content-Type: application/json

{
  "name": "Active Subscribers",
  "options": {
    "match": "all",
    "conditions": [
      {
        "condition_type": "EmailActivity",
        "field": "opened",
        "op": "date_within",
        "value": "30"
      }
    ]
  }
}

Update a Segment

PATCH /mailchimp/3.0/lists/{list_id}/segments/{segment_id}

Get Segment Members

GET /mailchimp/3.0/lists/{list_id}/segments/{segment_id}/members

Delete a Segment

DELETE /mailchimp/3.0/lists/{list_id}/segments/{segment_id}

Returns 204 No Content on success.

Campaigns

Get All Campaigns

GET /mailchimp/3.0/campaigns

Query parameters:

• type - Campaign type (regular, plaintext, absplit, rss, variate)
• status - Campaign status (save, paused, schedule, sending, sent)
• list_id - Filter by list ID
• count - Number of records to return
• offset - Number of records to skip

Example:

python <<'EOF'
import urllib.request, os, json
req = urllib.request.Request('https://gateway.maton.ai/mailchimp/3.0/campaigns?status=sent&count=20')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

Response:

{
  "campaigns": [
    {
      "id": "campaign123",
      "type": "regular",
      "status": "sent",
      "settings": {
        "subject_line": "Monthly Newsletter",
        "from_name": "Acme Corp"
      },
      "send_time": "2025-02-01T10:00:00Z",
      "report_summary": {
        "opens": 1500,
        "clicks": 300,
        "open_rate": 0.30,
        "click_rate": 0.06
      }
    }
  ],
  "total_items": 50
}

Get a Campaign

GET /mailchimp/3.0/campaigns/{campaign_id}

Create a Campaign

POST /mailchimp/3.0/campaigns
Content-Type: application/json

{
  "type": "regular",
  "recipients": {
    "list_id": "abc123def4"
  },
  "settings": {
    "subject_line": "Your Monthly Update",
    "from_name": "Acme Corp",
    "reply_to": "hello@acme.com"
  }
}

Example:

python <<'EOF'
import urllib.request, os, json
data = json.dumps({'type': 'regular', 'recipients': {'list_id': 'abc123def4'}, 'settings': {'subject_line': 'February Newsletter', 'from_name': 'Acme Corp', 'reply_to': 'newsletter@acme.com'}}).encode()
req = urllib.request.Request('https://gateway.maton.ai/mailchimp/3.0/campaigns', 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

Update a Campaign

PATCH /mailchimp/3.0/campaigns/{campaign_id}

Delete a Campaign

DELETE /mailchimp/3.0/campaigns/{campaign_id}

Returns 204 No Content on success.

Get Campaign Content

GET /mailchimp/3.0/campaigns/{campaign_id}/content

Set Campaign Content

PUT /mailchimp/3.0/campaigns/{campaign_id}/content
Content-Type: application/json

{
  "html": "<html><body><h1>Hello!</h1><p>Newsletter content here.</p></body></html>",
  "plain_text": "Hello! Newsletter content here."
}

Or use a template:

PUT /mailchimp/3.0/campaigns/{campaign_id}/content
Content-Type: application/json

{
  "template": {
    "id": 12345,
    "sections": {
      "body": "<p>Custom content for the template section</p>"
    }
  }
}

Get Campaign Send Checklist

Check if a campaign is ready to send:

GET /mailchimp/3.0/campaigns/{campaign_id}/send-checklist

Send a Campaign

POST /mailchimp/3.0/campaigns/{campaign_id}/actions/send

Schedule a Campaign

POST /mailchimp/3.0/campaigns/{campaign_id}/actions/schedule
Content-Type: application/json

{
  "schedule_time": "2025-03-01T10:00:00+00:00"
}

Cancel a Scheduled Campaign

POST /mailchimp/3.0/campaigns/{campaign_id}/actions/cancel-send

Templates

Get All Templates

GET /mailchimp/3.0/templates

Query parameters:

• type - Template type (user, base, gallery)
• count - Number of records to return
• offset - Number of records to skip

Example:

python <<'EOF'
import urllib.request, os, json
req = urllib.request.Request('https://gateway.maton.ai/mailchimp/3.0/templates?type=user')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

Get a Template

GET /mailchimp/3.0/templates/{template_id}

Get Template Default Content

GET /mailchimp/3.0/templates/{template_id}/default-content

Create a Template

POST /mailchimp/3.0/templates
Content-Type: application/json

{
  "name": "Newsletter Template",
  "html": "<html><body mc:edit=\"body\"><h1>Title</h1><p>Content here</p></body></html>"
}

Update a Template

PATCH /mailchimp/3.0/templates/{template_id}

Delete a Template

DELETE /mailchimp/3.0/templates/{template_id}

Returns 204 No Content on success.

Automations

Mailchimp's classic automations let you build email series triggered by dates, activities, or events.

Get All Automations

GET /mailchimp/3.0/automations

Example:

python <<'EOF'
import urllib.request, os, json
req = urllib.request.Request('https://gateway.maton.ai/mailchimp/3.0/automations')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

Get an Automation

GET /mailchimp/3.0/automations/{workflow_id}

Start an Automation

POST /mailchimp/3.0/automations/{workflow_id}/actions/start-all-emails

Pause an Automation

POST /mailchimp/3.0/automations/{workflow_id}/actions/pause-all-emails

Get Automation Emails

GET /mailchimp/3.0/automations/{workflow_id}/emails

Add Subscriber to Automation Queue

Manually add a subscriber to an automation workflow:

POST /mailchimp/3.0/automations/{workflow_id}/emails/{workflow_email_id}/queue
Content-Type: application/json

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

Reports

Get Campaign Reports

GET /mailchimp/3.0/reports

Query parameters:

• count - Number of records to return
• offset - Number of records to skip
• type - Campaign type

Example:

python <<'EOF'
import urllib.request, os, json
req = urllib.request.Request('https://gateway.maton.ai/mailchimp/3.0/reports?count=20')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

Response:

{
  "reports": [
    {
      "id": "campaign123",
      "campaign_title": "Monthly Newsletter",
      "emails_sent": 5000,
      "opens": {
        "opens_total": 1500,
        "unique_opens": 1200,
        "open_rate": 0.24
      },
      "clicks": {
        "clicks_total": 450,
        "unique_clicks": 300,
        "click_rate": 0.06
      },
      "unsubscribed": 10,
      "bounce_rate": 0.02
    }
  ]
}

Get Campaign Report

GET /mailchimp/3.0/reports/{campaign_id}

Get Campaign Open Details

GET /mailchimp/3.0/reports/{campaign_id}/open-details

Get Campaign Click Details

GET /mailchimp/3.0/reports/{campaign_id}/click-details

Get List Activity

GET /mailchimp/3.0/lists/{list_id}/activity

Returns recent daily aggregated activity stats (unsubscribes, signups, opens, clicks) for up to 180 days.

Batch Operations

Process multiple operations in a single call.

Create Batch Operation

POST /mailchimp/3.0/batches
Content-Type: application/json

{
  "operations": [
    {
      "method": "POST",
      "path": "/lists/abc123def4/members",
      "body": "{\"email_address\":\"user1@example.com\",\"status\":\"subscribed\"}"
    },
    {
      "method": "POST",
      "path": "/lists/abc123def4/members",
      "body": "{\"email_address\":\"user2@example.com\",\"status\":\"subscribed\"}"
    }
  ]
}

Get Batch Status

GET /mailchimp/3.0/batches/{batch_id}

List All Batches

GET /mailchimp/3.0/batches

Delete a Batch

DELETE /mailchimp/3.0/batches/{batch_id}

Returns 204 No Content on success.

Pagination

Mailchimp uses offset-based pagination:

python <<'EOF'
import urllib.request, os, json
req = urllib.request.Request('https://gateway.maton.ai/mailchimp/3.0/lists?count=50&offset=100')
req.add_header('Authorization', f'Bearer {os.environ["MATON_API_KEY"]}')
print(json.dumps(json.load(urllib.request.urlopen(req)), indent=2))
EOF

Response includes total_items for calculating total pages:

{
  "lists": [...],
  "total_items": 250
}

Code Examples

JavaScript

const response = await fetch(
  'https://gateway.maton.ai/mailchimp/3.0/lists',
  {
    headers: {
      'Authorization': `Bearer ${process.env.MATON_API_KEY}`
    }
  }
);
const data = await response.json();

Python

import os
import requests
import hashlib

# Get lists
response = requests.get(
    'https://gateway.maton.ai/mailchimp/3.0/lists',
    headers={'Authorization': f'Bearer {os.environ["MATON_API_KEY"]}'}
)
data = response.json()

# Add a subscriber
list_id = 'abc123def4'
email = 'newuser@example.com'

response = requests.post(
    f'https://gateway.maton.ai/mailchimp/3.0/lists/{list_id}/members',
    headers={
        'Authorization': f'Bearer {os.environ["MATON_API_KEY"]}',
        'Content-Type': 'application/json'
    },
    json={
        'email_address': email,
        'status': 'subscribed'
    }
)

# Get subscriber hash for updates
subscriber_hash = hashlib.md5(email.lower().encode()).hexdigest()

Notes

• List IDs are 10-character alphanumeric strings
• Subscriber hashes are MD5 hashes of lowercase email addresses
• Timestamps are in ISO 8601 format
• The API has a 120-second timeout on calls
• Maximum 1000 records per request for list endpoints
• "Audience" and "list" are used interchangeably (app vs API terminology)
• "Contact" and "member" are used interchangeably (app vs API terminology)
• IMPORTANT: When using curl commands, use curl -g when URLs contain brackets (fields[], sort[], records[]) 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. You may get "Invalid API key" errors when piping.

Response Codes

Mailchimp error responses include detailed information:

{
  "type": "https://mailchimp.com/developer/marketing/docs/errors/",
  "title": "Invalid Resource",
  "status": 400,
  "detail": "The resource submitted could not be validated.",
  "instance": "abc123-def456",
  "errors": [
    {
      "field": "email_address",
      "message": "This value should be a valid email."
    }
  ]
}

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

• Mailchimp Marketing API Documentation
• API Reference
• Quick Start Guide
• Release Notes