String MCP for AI. Send segmented SMS and MMS from your agent.
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String connects your AI agent directly to business messaging features. Use it to send SMS and MMS messages, manage contacts, view conversation history, and run marketing campaigns.
You can list all tags for segmentation, create new contacts, or check API connectivity status with a single tool call.
What your AI can do
Check string status
Verifies the API connection status between your agent and String.
Create contact
Adds a new contact entry to the system using required details.
Get contact
Retrieves all specific information about one contact by ID or phone number.
Your agent sends specific text or media messages (SMS/MMS) to any phone number.
The system allows your agent to list all existing contacts, retrieve details on single contacts, and create new entries.
You can view active conversation threads or fetch detailed records for past messages and conversations.
The agent lists existing marketing campaigns to ensure the outreach parameters are correct before sending mass communications.
You can list all available contact tags, which lets your AI client segment users for highly targeted messaging runs.
Ask an AI about this
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String MCP Server: 10 Tools for Messaging Management
These tools let your AI client perform all aspects of business messaging—from checking connectivity to sending targeted SMS/MMS campaigns.
Make your AI actually useful.
Add this MCP to Claude, Cursor, or Windsurf and your AI stops guessing. It gets real tools to look things up, take action, and handle the stuff you keep doing by hand.
Start using String on VinkiusCheck String Status
Verifies the API connection status between your agent and String.
Create Contact
Adds a new contact entry to the system using required details.
Get Contact
Retrieves all specific information about one contact by ID or phone number.
Get Message
Fetches the full content and metadata for a single message ID.
List Campaigns
Retrieves a list of all existing SMS marketing campaigns.
List Contacts
Generates a complete list of every contact currently stored in the system.
List Conversations
Lists all active or recent conversation threads associated with users.
List Messages
Retrieves a paginated list of messages, allowing you to filter by date or user.
List Tags
Shows all available tags used for organizing and segmenting contacts.
Send Message
Sends a new text message (SMS/MMS) to the specified phone number.
Security and governance baked right in.
Pick your AI client below to get set up. Just create a Vinkius account, subscribe, and you're instantly up and running. We handle the entire backend infrastructure, delivering out-of-the-box support for HTTPS Streamable, SSE, and OAuth2—zero messy routing required.
Claude AI
Open Claude Settings
Go to claude.ai, click your profile icon, then navigate to Customize → Connectors.
Add Custom Connector
Click the "+" button and select Add custom connector. Paste your Vinkius endpoint URL:
https://edge.vinkius.com/[YOUR_TOKEN_HERE]/mcp
Replace [YOUR_TOKEN_HERE] with your token
from cloud.vinkius.com. For OAuth-protected servers, expand
Advanced settings to add credentials.
Start a conversation
Open a new chat. The String integration is available immediately — no restart needed.
Choose How to Get Started
Build a custom MCP for your own tools, or connect a ready-made integration from our catalog.
Build Your Own
Turn any API into an MCP. Import a spec, define Agent Skills, or deploy with MCPFusion.
- Import from OpenAPI, Swagger, or YAML specs
- Create Agent Skills with progressive disclosure
- Deploy to edge with MCPFusion framework
- Built in DLP, auth, and compliance on every call
- Real time usage dashboard and cost metering
- Publish to catalog or keep private
Make Your AI Do More
Start with String, then connect any of our 5,100+ other servers whenever your AI needs more. One click, no limits.
- Use this MCP plus 5,100+ others, all in one place
- Add new capabilities to your AI anytime you want
- Every connection is secured and compliant automatically
- Track usage and costs across all your servers
- Works with Claude, ChatGPT, Cursor, and more
- New servers added to the catalog every week
Independent Platform Disclaimer: Vinkius is an independent platform and is not affiliated with, endorsed by, sponsored by, verified by, or otherwise authorized by String. All third-party trademarks, logos, and brand names are the property of their respective owners. Their use on this website is strictly for informational purposes to identify service compatibility and interoperability.
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Works with Claude, ChatGPT, Cursor, and more
The Model Context Protocol standardizes how applications expose capabilities to LLMs. Instead of operating in isolation, your AI gains direct access to external platforms, live data, and real-world actions through secure, standardized connections.
This connection provides 10 powerful capabilities that interface natively with Claude, ChatGPT, Cursor, and other compatible AI platforms. No middleware. No custom integration required.
Keeping track of who talked to whom is a mess.
Today, if you want to know what was discussed with a client over the last week, you have to jump between the chat dashboard, the contact record tab, and maybe even check an external spreadsheet. It's manual copying, pasting, and guessing which thread is the current one.
With this MCP server, your agent handles it in two steps. You ask for `list_conversations`. The agent gives you a clean list of threads. From there, calling `get_message` pulls up exactly what was said—no more clicking through five different tabs just to get context.
String MCP Server: Send messages with zero friction.
The biggest time sink is the launch sequence. You need to check if your credentials are okay, then list who you can message, and *then* send it all in separate actions. It feels like a checklist for an intern.
Now, your agent handles this flow. You just tell it: 'Send a welcome text.' The server autonomously checks status (`check_string_status`), pulls the contact details (`get_contact`), and executes `send_message`—all in one go. It’s done.
What your AI can actually do with this
String connects your agent right to your business messaging features. Forget jumping between separate dashboards just to manage outreach; your AI client handles everything—from checking contact details to firing off a full MMS campaign using one tool call.
Connectivity and Setup
You gotta make sure the connection's solid first. You can run check_string_status to verify if your agent is actually talking to String's API, so you don't waste time trying to send messages when the link's down.
Managing Contacts
The system gives you full control over who you're messaging. Use list_contacts to pull a complete list of every single contact stored in your database. Need details on just one person? You can use get_contact, giving it an ID or a phone number, and you get all their specific info back.
If you find a new lead, you don't have to manually enter them anywhere; run create_contact and drop in the required details straight away. Furthermore, for segmentation, you can use list_tags to see every tag available—that lets your agent segment users into tight groups for super targeted messaging runs.
Sending Messages (SMS/MMS)
When it's time to talk, send_message sends a brand new text message or an MMS to whatever phone number you specify. This is how you fire off the actual communications.
Tracking Conversations and History
You don't wanna send something without knowing what was said before. You can use list_conversations to pull up a list of all active or recent threads associated with your users. If you need the raw details, running get_message lets you fetch the full content and metadata for any single message ID.
To get a broader picture, list_messages pulls back a paginated list of messages, letting you filter that history by date or even by specific user.
Running Campaigns
Before sending out anything big, your agent needs to know what's going on. You can use list_campaigns to retrieve a full rundown of all existing SMS marketing campaigns, confirming the parameters are right before you start mass communications.
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Here's how it actually works
The bottom line is that your AI client performs multi-step outreach—from checking status to segmenting users—without needing multiple manual logins or API calls.
First, use check_string_status to verify the connection and ensure API connectivity is active.
Next, run list_contacts or list_tags to identify the specific users or segments you need to reach.
Finally, call send_message, providing the recipient's number and the message content. The agent handles the delivery tracking.
Who is this actually for?
This server is for Marketing Operations Managers and Customer Support Leads who spend too much time manually coordinating segmented, outbound messaging. If your process involves sending different messages to different user groups based on their last activity (e.g., 'Did they open the email?'), this tool saves you from clicking through dozens of dashboards.
Uses list_campaigns and list_tags to define outreach parameters, then calls send_message to launch segmented SMS campaigns.
Retrieves customer history using list_conversations and get_message before responding via send_message to keep the chat thread continuous.
Uses create_contact to onboard new users immediately after sign-up, ensuring they are ready for initial campaign messaging.
What Changes When You Connect
Automate segmentation: Instead of manually filtering spreadsheets, use list_tags to get all available categories. Your agent then uses that list to target only the 'High-Value' users when calling send_message.
Maintain a full history: When responding to a customer, your agent doesn't guess what was said before. It calls list_conversations and get_message first, ensuring the reply is relevant to the entire thread.
Reduce setup time: Need to test an outreach flow? Use check_string_status at the start of your script. This confirms API connectivity instantly so you don't waste time sending messages that fail due to authentication issues.
Onboard contacts fast: When a user signs up, instead of waiting for manual input, your agent runs create_contact immediately. The new record is ready for campaigns and messaging tools right away.
Run structured outreach: Use list_campaigns before launching any mass message. This lets you verify the campaign's scope and history without having to navigate the web UI.
See it in action
Onboarding a New Lead
A Product Owner gets a new lead phone number. Instead of manually entering it, they ask their agent to create_contact. The agent adds the contact, tags them as 'New Sign-up', and then immediately uses send_message to send the welcome text.
Reactivating a Dormant Customer
A Marketing Manager wants to re-engage users who haven't logged in for 60 days. They ask their agent to list_tags to find the 'Dormant' tag. The agent filters all contacts by that tag and runs an MMS campaign using send_message.
Investigating a Support Issue
A Customer Support Specialist gets a complaint about message delivery. They ask their agent to run list_conversations to see the timeline, then use get_message on the specific message ID to confirm if it was delivered or if there's an error.
Pre-Flight Check for Mass Outreach
Before launching a major seasonal campaign, the team needs to know if their API credentials are valid. They start by calling check_string_status. The agent confirms connectivity before proceeding to list contacts or run any campaigns.
The honest tradeoffs
Assuming contact data is always fresh
The developer tries to send a message using only the name, failing because they didn't verify the phone number first.
Always start by calling get_contact with the user's ID. This confirms that all necessary fields—like the current phone number—are populated before running any messaging tool like send_message.
Mixing up message viewing and history
The agent uses list_messages but gets a massive, unfilterable list of old messages, making it hard to find the specific thread needed.
Use list_conversations first. This narrows down the results to active threads, allowing you to then use get_message on a single conversation ID for precise history retrieval.
Skipping segmentation checks
Running a general campaign using send_message that blasts everyone, resulting in irrelevant messages sent to users who shouldn't get them.
First, use list_tags to see your available segments. Then, use the tag data when calling list_contacts to pull only the relevant group before sending.
When It Fits, When It Doesn't
Use this server if your core pain point is executing multi-step outbound communication or managing contact records via SMS/MMS. You need a single tool that lets your agent move from 'Who are they?' (list_contacts, get_contact) to 'What did we say?' (list_conversations) to 'Send this now' (send_message).
Don't use it if your primary need is managing email workflows, or dealing with internal ticketing systems. For those tasks, you should look at specialized email API servers (like SendGrid) or CRM integration tools. If the task involves complex web form submission instead of messaging, a general HTTP request tool might be better.
Questions you might have
How do I send a message to only users who are 'VIP'? +
First, use list_tags to confirm the tag name is correct. Then, your agent uses that tag name when calling list_contacts. Finally, it runs send_message against the resulting list of contacts.
What if I need to know if my API key is working before I send anything? +
You run check_string_status. This tool confirms connectivity and verifies your credentials immediately. If it fails, you know the problem is authentication, not your code.
Can I get the message history for a specific user ID? +
Yes. You first use list_conversations to find the thread ID, and then pass that ID into get_message. This pulls up the full message record you need.
Does String MCP Server handle MMS messages, or just text? +
It handles both. The send_message tool supports sending multimedia messages (MMS) in addition to standard SMS text messages.
When I use the `list_campaigns` tool, how do I see all active SMS marketing efforts for String? +
The list_campaigns tool returns all existing marketing campaigns. It gives you campaign IDs, names, and current statuses. You use this to quickly inventory every active or paused effort managed by String.
Before running the `send_message` tool, how can I make sure I have a clean record of the recipient with String? +
You should use the create_contact tool. This lets you register new people in your system first. It ensures that all future messages sent via String are tied to a verified contact profile, which is key for tracking.
What does the `list_tags` tool show me about my current customer segments in String? +
The list_tags tool shows you every tag group attached to your contacts. It's how you verify which segmentation labels exist before running a targeted send. You get the full list of available categories for filtering.
If I know an ID, how do I use the `get_contact` tool to retrieve all specific information on a user from String? +
The get_contact tool pulls all available data for one specific contact ID. You get details like their full name and phone number, which is better than just listing them if you need to validate the data structure before use.
Can my AI send text messages? +
Yes. Use send_message with the recipient phone number and message text. The agent delivers it via String.
Can I view conversation history? +
Yes. list_conversations shows all active threads, and list_messages returns full message history.
Can I create contacts through the AI? +
Yes. create_contact adds a new contact with name and phone number to your String directory.
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