Customer.io MCP Server
for AI Agents
Connect your AI agent to StackOne's Customer.io MCP server and give it 57 MCP tools out of the box. Auth, tool execution, and security all managed.
StackOne 
Coverage
57 Agent Actions
Create, read, update, and delete across Customer.io — and extend your agent's capabilities with custom actions.
Authentication
Agent Tool Authentication
Per-user OAuth in one call. Your Customer.io MCP server gets session-scoped tokens with zero credentials stored on your infra.
Agent Auth →
Security
Agent Protection
Every Customer.io tool response scanned for prompt injection in milliseconds — 88.7% accuracy, all running on CPU.
Prompt Injection Defense →
Performance
Max Agent Context. Min Cost.
Free up to 96% of your agent's context window to enhance reasoning and reduce cost, on every Customer.io call.
Tools Discovery →What is the Customer.io MCP Server?
A Customer.io MCP server lets AI agents read and write Customer.io data through the Model Context Protocol — Anthropic's open standard for connecting LLMs to external tools. StackOne's Customer.io MCP server ships with 57 pre-built actions, fully extensible via the Connector Builder — plus managed authentication, prompt injection defense, observability, and agent execution runtime. Connect it from MCP clients like Claude Desktop, Claude Code, Cursor, Goose, and VS Code, or from agent frameworks like OpenAI Agents SDK, LangChain, and Vercel AI SDK.
All Customer.io MCP Tools
Every action from Customer.io's API, ready for your agent. Create, read, update, and delete — scoped to exactly what you need.
Broadcasts
- List Broadcasts
List all broadcasts in the workspace
- Get Broadcast
Retrieve a specific broadcast by ID
Campaigns
- List Campaigns
List all campaigns in the workspace
- Get Campaign
Retrieve a specific campaign by ID
Messages
- List Messages
List all messages in the workspace
- Get Message
Retrieve a specific message by ID
Newsletters
- List Newsletters
List all newsletters in the workspace
- Get Newsletter
Retrieve a specific newsletter by ID
Segments
- List Segments
List all segments in the workspace
- Get Segment
Retrieve a specific segment by ID
Snippets
- Create Snippet
Create a new snippet
- List Snippets
List all snippets in the workspace
- Update Snippet
Create or update a snippet
- Delete Snippet
Delete a snippet
Other (43)
- Create And Send A Newsletter
Create a newsletter
- Create A Manual Segment
Create a manual segment
- Add Or Update A Customer
Add or update a customer
- Add Or Update A Customer Device
Add or update a customer device
- Add Customers To Segment
Add customers to a manual segment
- List Activities
List all activities in the workspace
- Get Broadcast Metrics
Get metrics for a broadcast
- List Broadcast Actions
List all actions in a broadcast
- Get Broadcast Triggers
Get trigger history for a broadcast
- Get Campaign Metrics
Get metrics for a campaign
- List Campaign Actions
List all actions in a campaign
- List Collections
List all collections
- Get Customers By Email
Get customers by email address
- Search For Customers
Search for customers using advanced filters
- List Customers, Attributes, And Devices
List customers with their attributes and devices
- List Exports
List all exports
- Get Newsletter Metrics
Get metrics for a newsletter
- Get Newsletter Link Metrics
Get link click metrics for a newsletter
- List Object Types
List all object types
- List Reporting Webhooks
List all reporting webhooks
- Get A Segment Customer Count
Get the total number of customers in a segment
- List Customers In A Segment
List all customers in a specific segment
- List Sender Identities
List all sender identities in the workspace
- Get Sender Identity
Retrieve a specific sender identity by ID
- Get Account Region
Find your account region
- List Transactional Messages
List all transactional messages
- Get A Transactional Message
Retrieve a specific transactional message by ID
- Delete A Newsletter
Delete a specific newsletter
- Delete A Segment
Delete a specific segment
- Delete A Customer
Delete a customer
- Delete A Customer Device
Delete a customer device
- Remove Customers From Segment
Remove customers from a manual segment
- Lookup A Customer's Attributes
Get attributes for a specific customer
- Lookup A Customer's Segments
Get segments a customer belongs to
- Lookup Messages Sent To A Customer
Get messages sent to a customer
- Lookup A Customer's Activities
Get activities for a customer
- Lookup A Customer's Relationships
Get relationships for a specific customer
- Find Objects
Find objects using filter conditions
- Merge Duplicate People
Merge duplicate customers
- Track Customer Event
Track an event for a customer
- Track Anonymous Event
Track an event for an anonymous user
- Suppress A Customer Profile
Suppress a customer profile
- Unsuppress A Customer Profile
Unsuppress a customer profile
Customer.io AI Agent Use Cases
Connect your AI agent to Customer.io and help your team scale the marketing operations they run by hand today.
Use StackOne to connect your AI agent to your marketing automation, CRM, and email tools to automate lead nurture email sequences.
ViewUse StackOne to connect your AI agent to your marketing automation, email, and analytics platforms to automate campaign performance reporting.
ViewUse StackOne to connect your AI agent to your document stores, email platforms, and messaging tools to automate content repurposing and distribution.
ViewSet Up Your Customer.io MCP Server in Minutes
One endpoint. Any framework. Your agent is talking to Customer.io in under 10 lines of code.
Agent Frameworks
JSON{
"mcpServers": {
"stackone": {
"command": "npx",
"args": [
"-y",
"mcp-remote@latest",
"https://api.stackone.com/mcp?x-account-id=<account_id>",
"--header",
"Authorization: Basic <YOUR_BASE64_TOKEN>"
]
}
}
}Platform Resources
MCP Code Mode: Keeping Tool Responses Out of Agent Context
Anthropic's code_execution processes data already in context. Custom MCP code mode keeps raw tool responses in a sandbox. 14K tokens vs 500.
11 min
Comparing BM25, TF-IDF, and Hybrid Search for MCP Tool Discovery
Benchmarking BM25, TF-IDF, and hybrid search for MCP tool discovery across 916 tools. The 80/20 TF-IDF/BM25 hybrid hits 21% Top-1 accuracy in under 1ms.
10 min
Indirect Prompt Injection Defense for MCP Tools: A Technical Guide
MCP tools that read emails, CRM records, and tickets are indirect prompt injection vectors. Here's how we built a two-tier defense that scans tool results in ~11ms.
12 min
MCP vs A2A: Architecture, Security, and When to Use Each
MCP vs A2A: what each protocol standardizes, how they differ, their shared security risks including indirect prompt injection, and when to use one, both, or a hybrid architecture.
12 min
MCP vs API: What 200+ Connector Builds Taught Us
MCP wraps APIs, it doesn't replace them. After building 200+ connectors that serve both, here's when each approach wins.
14 min read
Customer.io MCP Server FAQ
Does StackOne have a Customer.io MCP server?
Customer.io MCP server vs direct API integration — what's the difference?
How does Customer.io authentication work for AI agents?
origin_owner_id.Are Customer.io MCP tools vulnerable to prompt injection?
What is the context bloat of a Customer.io agent and how do I avoid it?
Can I limit which actions my Customer.io agent can access?
Can I create custom agent actions for my Customer.io MCP server?
When should I NOT use a Customer.io MCP server?
What AI frameworks and AI clients does the StackOne Customer.io MCP server support?
Put your AI agents to work
All the tools you need to build and scale AI agent integrations, with best-in-class connectivity, execution, and security.