Automate ConvertKit (now known as Kit) email marketing operations through Composio's Kit toolkit via Rube MCP.
Toolkit docs
:
composio.dev/toolkits/kit
Prerequisites
Rube MCP must be connected (RUBE_SEARCH_TOOLS available)
Active Kit connection via
RUBE_MANAGE_CONNECTIONS
with toolkit
kit
Always call
RUBE_SEARCH_TOOLS
first to get current tool schemas
Setup
Get Rube MCP
Add
https://rube.app/mcp
as an MCP server in your client configuration. No API keys needed — just add the endpoint and it works.
Verify Rube MCP is available by confirming
RUBE_SEARCH_TOOLS
responds
Call
RUBE_MANAGE_CONNECTIONS
with toolkit
kit
If connection is not ACTIVE, follow the returned auth link to complete Kit authentication
Confirm connection status shows ACTIVE before running any workflows
Core Workflows
1. List and Search Subscribers
When to use
User wants to browse, search, or filter email subscribers
Tool sequence
:
KIT_LIST_SUBSCRIBERS
- List subscribers with filters and pagination [Required]
Key parameters
:
status
Filter by status ('active' or 'inactive')
email_address
Exact email to search for
created_after
/
created_before
Date range filter (YYYY-MM-DD)
updated_after
/
updated_before
Date range filter (YYYY-MM-DD)
sort_field
Sort by 'id', 'cancelled_at', or 'updated_at'
sort_order
'asc' or 'desc'
per_page
Results per page (min 1)
after
/
before
Cursor strings for pagination
include_total_count
Set to 'true' to get total subscriber count
Pitfalls
:
If
sort_field
is 'cancelled_at', the
status
must be set to 'cancelled'
Date filters use YYYY-MM-DD format (no time component)
email_address
is an exact match; partial email search is not supported
Pagination uses cursor-based approach with
after
/
before
cursor strings
include_total_count
is a string 'true', not a boolean
2. Manage Subscriber Tags
When to use
User wants to tag subscribers for segmentation
Tool sequence
:
KIT_LIST_SUBSCRIBERS
- Find subscriber ID by email [Prerequisite]
KIT_TAG_SUBSCRIBER
- Associate a subscriber with a tag [Required]
KIT_LIST_TAG_SUBSCRIBERS
- List subscribers for a specific tag [Optional]
Key parameters for tagging
:
tag_id
Numeric tag ID (required)
subscriber_id
Numeric subscriber ID (required)
Pitfalls
:
Both
tag_id
and
subscriber_id
must be positive integers
Tag IDs must reference existing tags; tags are created via the Kit web UI
Tagging an already-tagged subscriber is idempotent (no error)
Subscriber IDs are returned from LIST_SUBSCRIBERS; use
email_address
filter to find specific subscribers
3. Unsubscribe a Subscriber
When to use
User wants to unsubscribe a subscriber from all communications
Tool sequence
:
KIT_LIST_SUBSCRIBERS
- Find subscriber ID [Prerequisite]
KIT_DELETE_SUBSCRIBER
- Unsubscribe the subscriber [Required]
Key parameters
:
id
Subscriber ID (required, positive integer)
Pitfalls
:
This permanently unsubscribes the subscriber from ALL email communications
The subscriber's historical data is retained but they will no longer receive emails
Operation is idempotent; unsubscribing an already-unsubscribed subscriber succeeds without error
Returns empty response (HTTP 204 No Content) on success
Subscriber ID must exist; non-existent IDs return 404
4. List and View Broadcasts
When to use
User wants to browse email broadcasts or get details of a specific one
Tool sequence
:
KIT_LIST_BROADCASTS
- List all broadcasts with pagination [Required]
KIT_GET_BROADCAST
- Get detailed information for a specific broadcast [Optional]
KIT_GET_BROADCAST_STATS
- Get performance statistics for a broadcast [Optional]
Key parameters for listing
:
per_page
Results per page (1-500)
after
/
before
Cursor strings for pagination
include_total_count
Set to 'true' for total count
Key parameters for details
:
id
Broadcast ID (required, positive integer)
Pitfalls
:
per_page
max is 500 for broadcasts
Broadcast stats are only available for sent broadcasts
Draft broadcasts will not have stats
Broadcast IDs are numeric integers
5. Delete a Broadcast
When to use
User wants to permanently remove a broadcast
Tool sequence
:
KIT_LIST_BROADCASTS
- Find the broadcast to delete [Prerequisite]
KIT_GET_BROADCAST
- Verify it is the correct broadcast [Optional]
KIT_DELETE_BROADCAST
- Permanently delete the broadcast [Required]
Key parameters
:
id
Broadcast ID (required)
Pitfalls
:
Deletion is permanent and cannot be undone
Deleting a sent broadcast removes it but does not unsend the emails
Confirm the broadcast ID before deleting
Common Patterns
Subscriber Lookup by Email
1. Call KIT_LIST_SUBSCRIBERS with email_address='user@example.com'
2. Extract subscriber ID from the response
3. Use ID for tagging, unsubscribing, or other operations
Pagination
Kit uses cursor-based pagination:
Check response for
after
cursor value
Pass cursor as
after
parameter in next request
Continue until no more cursor is returned
Use
include_total_count: 'true'
to track progress
Tag-Based Segmentation
1. Create tags in Kit web UI
2. Use KIT_TAG_SUBSCRIBER to assign tags to subscribers
3. Use KIT_LIST_TAG_SUBSCRIBERS to view subscribers per tag
Known Pitfalls
ID Formats
:
Subscriber IDs: positive integers (e.g., 3887204736)
Tag IDs: positive integers
Broadcast IDs: positive integers
All IDs are numeric, not strings
Status Values
:
Subscriber statuses: 'active', 'inactive', 'cancelled'
Some operations are restricted by status (e.g., sorting by cancelled_at requires status='cancelled')
String vs Boolean Parameters
:
include_total_count
is a string 'true', not a boolean true
sort_order
is a string enum: 'asc' or 'desc'
Rate Limits
:
Kit API has per-account rate limits
Implement backoff on 429 responses
Bulk operations should be paced appropriately
Response Parsing
:
Response data may be nested under
data
or
data.data
Parse defensively with fallback patterns
Cursor values are opaque strings; use exactly as returned
Quick Reference
Task
Tool Slug
Key Params
List subscribers
KIT_LIST_SUBSCRIBERS
status, email_address, per_page
Tag subscriber
KIT_TAG_SUBSCRIBER
tag_id, subscriber_id
List tag subscribers
KIT_LIST_TAG_SUBSCRIBERS
tag_id
Unsubscribe
KIT_DELETE_SUBSCRIBER
id
List broadcasts
KIT_LIST_BROADCASTS
per_page, after
Get broadcast
KIT_GET_BROADCAST
id
Get broadcast stats
KIT_GET_BROADCAST_STATS
id
Delete broadcast
KIT_DELETE_BROADCAST
id
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