# How to connect Carbon Voice MCP to Claude ```json { "title": "How to connect Carbon Voice MCP to Claude", "toolkit": "Carbon Voice MCP", "toolkit_slug": "carbon_voice_mcp", "framework": "Claude Cowork", "framework_slug": "claude-cowork", "url": "https://composio.dev/toolkits/carbon_voice_mcp/framework/claude-cowork", "markdown_url": "https://composio.dev/toolkits/carbon_voice_mcp/framework/claude-cowork.md", "updated_at": "2026-09-02T05:34:34.408Z" } ``` ## Introduction Claude is Anthropic's AI assistant, available on the web, in the desktop app, and on mobile. Cowork is its agent for knowledge work, and it runs on all of those surfaces too. Connected to your apps, Claude can work with your files and services to accomplish complex tasks on your behalf. This guide walks you through the easiest and most secure way to connect your Carbon Voice account to Claude via Composio Connect, enabling it to summarize today's missed voice messages, send a voice reply to Alice, list active conversations needing follow up, and more such actions on your behalf without compromising your account security. Setup is the same on Claude Web, Desktop, and Cowork, and you only need to do it once. The connector is tied to your account, so it's available in all three. ## Also integrate Carbon Voice MCP with - [ChatGPT](https://composio.dev/toolkits/carbon_voice_mcp/framework/chatgpt) - [Hermes](https://composio.dev/toolkits/carbon_voice_mcp/framework/hermes-agent) ## Connect Carbon Voice MCP to Claude Cowork ### Connecting Carbon Voice to Claude Web, Desktop, and Cowork Two ways to add the Composio connector. Pick whichever you prefer. ### 1. Add with one click Click the button. Claude opens with the Composio connector filled in. Click Add, then go to step 2. [Add to Claude](https://claude.ai/customize/connectors?modal=add-custom-connector&connectorName=Composio&connectorUrl=https%3A%2F%2Fconnect.composio.dev%2Fmcp) ### Add manually In Claude Desktop, click Customize in the left sidebar, then select Connectors and click the + icon at the top. Click Add custom connector and paste in the Composio MCP server URL: ```bash https://connect.composio.dev/mcp ``` ## What is the Carbon Voice MCP server, and what's possible with it? The Carbon Voice MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Carbon Voice account. It provides structured and secure access so your agent can perform Carbon Voice operations on your behalf. ## Supported Tools | Tool slug | Name | Description | |---|---|---| | `CARBON_VOICE_MCP_ADD_ATTACHMENTS_TO_MESSAGE` | Add attachments to message | Add attachments to a message. In order to add attachments to a message, you must provide a message id and the attachments. | | `CARBON_VOICE_MCP_CREATE_CONVERSATION_MESSAGE` | Create conversation message | Sends a message to an existing conversation or any type with a conversation_id. To reply as a thread, included a message_id for "parent_id". You must provide a transcript or attachment. | | `CARBON_VOICE_MCP_CREATE_DIRECT_MESSAGE` | Create direct message | Send a Direct Message (DM) to a User or a Group of Users. In order to create a Direct Message, you must provide transcript or link attachments. | | `CARBON_VOICE_MCP_CREATE_FOLDER` | Create folder | Create a new folder. | | `CARBON_VOICE_MCP_CREATE_VOICEMEMO_MESSAGE` | Create voicememo message | Create a VoiceMemo Message. In order to create a VoiceMemo Message, you must provide a transcript or link attachments. | | `CARBON_VOICE_MCP_DELETE_FOLDER` | Delete folder | Delete a folder by its ID. Deleting a folder will also delete nested folders and all the messages in referenced folders. (This is a destructive action and cannot be undone, so please be careful.) | | `CARBON_VOICE_MCP_GET_AI_ACTION_RESPONSES` | Get ai action responses | Retrieve previously generated AI Action (Prompt) responses by filtering for a specific prompt, message, or conversation ID. Combine filters to narrow results and view all AI-generated responses related to a particular prompt, message, or conversation. | | `CARBON_VOICE_MCP_GET_CONVERSATION` | Get conversation | Get a conversation by its ID. | | `CARBON_VOICE_MCP_GET_CONVERSATION_USERS` | Get conversation users | Get users in a conversation. | | `CARBON_VOICE_MCP_GET_CURRENT_USER` | Get current user | Get the current user information. | | `CARBON_VOICE_MCP_GET_FOLDER` | Get folder | Get a folder by its ID. | | `CARBON_VOICE_MCP_GET_FOLDER_WITH_MESSAGES` | Get folder with messages | Get a folder including its messages by its ID. (Only messages at folder level are returned.) | | `CARBON_VOICE_MCP_GET_MESSAGE` | Get message | Get a message by its ID. | | `CARBON_VOICE_MCP_GET_RECENT_MESSAGES` | Get recent messages | Get most recent messages, including their associated Conversation, Creator, and Labels information. Returns a maximum of 10 messages. | | `CARBON_VOICE_MCP_GET_ROOT_FOLDERS` | Get root folders | Lists all root folders for a given workspace, including their names, IDs, and basic structure, but does not provide aggregate counts.(Required to inform message type:voicememo,prerecorded) | | `CARBON_VOICE_MCP_GET_USER` | Get user | Get detailed information about a specific user by their ID. Returns the full user profile — name, languages, voice settings, workspace memberships and roles, notification preferences, and timestamps. This is richer than `search_user` (which only finds users by phone, email, or name). Use this when you already have a user ID and need their complete information. | | `CARBON_VOICE_MCP_GET_WORKSPACES_BASIC_INFO` | Get workspaces basic info | Get basic information about a workspace. | | `CARBON_VOICE_MCP_LIST_AI_ACTIONS` | List ai actions | List AI Actions (Prompts). Optionally, you can filter by owner type and workspace id. Filtering by owner type, Possible values: "user", "workspace", "system". Do not use unless the user explicitly requests it. | | `CARBON_VOICE_MCP_LIST_CONVERSATIONS` | List conversations | List all conversations. Returns a simplified view of user conversations that have had messages sent or received within the last 6 months. Each result includes id, name, workspace_id, and type (directMessage, customerConversation, namedConversation, or asyncMeeting). | | `CARBON_VOICE_MCP_LIST_MESSAGES` | List messages | List Messages. By default returns latest 20 messages. The maximum allowed range between dates is 183 days (6 months). All presigned URLs returned by this tool are ready to use. Do not parse, modify, or re-encode them—always present or use the URLs exactly as received.If you want to get messages from a specific date range, you can use the "start_date" and "end_date" parameters. If you want to get messages from a specific date, you can use the "date" parameter. If you want to get messages from a specific user, you can use the "user_ids" parameter. If you want to get messages from a specific conversation, you can use the "conversation_id" parameter. If you want to get messages from a specific folder, you can use the "folder_id" parameter. If you want to get messages from a specific workspace, you can use the "workspace_id" parameter. If you want to get messages for a particular language, you can use the "language" parameter. | | `CARBON_VOICE_MCP_MOVE_FOLDER` | Move folder | Move a folder by its ID. Move a Folder into another Folder or into a Workspace. | | `CARBON_VOICE_MCP_MOVE_MESSAGE_TO_FOLDER` | Move message to folder | Move a message to a folder by its ID. Move a Message into another Folder or into a Workspace. Only allowed to move messages of type: voicememo,prerecorded. | | `CARBON_VOICE_MCP_RUN_AI_ACTION` | Run ai action | Run an AI Action (Prompt) for a message. You can run an AI Action for a message by its ID or a list of message IDs. | | `CARBON_VOICE_MCP_RUN_AI_ACTION_FOR_SHARED_LINK` | Run ai action for shared link | Run an AI Action (Prompt) for a shared link. You can run an AI Action for a shared link by its ID or a list of shared link IDs. You can also provide the language of the response. | | `CARBON_VOICE_MCP_SEARCH_USER` | Search user | Search for a User by their phone number, email address, id or name. (In order to search for a User, you must provide a phone number, email address, id or name.)When searching by name, only users that are part of your contacts will be returned | | `CARBON_VOICE_MCP_SEARCH_USERS` | Search users | Search multiple Users by their phone numbers, email addresses, ids or names. (In order to search Users, you must provide phone numbers, email addresses, ids or names.)When searching by name, only users that are part of your contacts will be returned | | `CARBON_VOICE_MCP_SUMMARIZE_CONVERSATION` | Summarize conversation | Summarize a conversation. | | `CARBON_VOICE_MCP_UPDATE_FOLDER_NAME` | Update folder name | Update a folder name by its ID. | ## Supported Triggers None listed. ## Troubleshooting ### 1. Why does Claude not use the Composio connector for Carbon Voice? The connector can show as connected, but Claude must use it in each Carbon Voice conversation. - Click + at the lower left of the chat, or type /. - Hover Connectors. - Turn on Composio. - Ask Claude to connect to Carbon Voice again. ### 2. Why does Claude show an MCP server error before Carbon Voice connects? Claude can show Couldn't reach the MCP server or Authorization with the MCP server failed when you add the connector for Carbon Voice. - Check that the connector URL is https://connect.composio.dev/mcp. - Connectors run from Anthropic's cloud, so your device network is usually not the problem. - Add the connector again from Customize > Connectors, then ask Claude to connect Carbon Voice. - If it fails again, send the error and the ofid_ reference id to support@composio.dev. ### 3. Why does the Carbon Voice authorization link not work? The Composio connector is one server. Your Carbon Voice account connects separately when Claude asks for it. - If the browser does not open, or the link expires, ask Claude to retry the Carbon Voice connection. - Composio creates a fresh Carbon Voice authorization link. - Open that link in your browser and finish the Carbon Voice sign-in. ### 4. Why do Carbon Voice actions fail after they worked before? The Carbon Voice connection can expire or lose permission. - Ask Claude to inspect the Carbon Voice connection. - If the connection is unhealthy, disconnect it when Claude prompts you. - Reconnect the Carbon Voice account and retry the action. - If Claude shows a permission prompt, approve it before Claude changes data in Carbon Voice. - If the action still fails with a permission error, check that the connected account has that permission in Carbon Voice itself. ### 5. How do I switch to a different Carbon Voice account? Claude can manage the Carbon Voice connection for you. - Ask Claude to disconnect or delete the current Carbon Voice account. - Ask Claude to connect Carbon Voice again. - Open the new Composio authorization link for Carbon Voice. - Sign in with the other Carbon Voice account in the browser. - After the account connects, ask Claude to retry the Carbon Voice task. ### 6. Why is my Carbon Voice connection missing in Claude Desktop or on a Team plan? The connector belongs to your Claude account, so your Carbon Voice connection works in Claude Web, Desktop, and Cowork. - In Claude Desktop, open Customize > Connectors. - Next to Composio, click ⋮ and click Clear cache. - If Carbon Voice tools still do not appear, click ⋮, disconnect, remove the connector, and add it again. - On Team or Enterprise, an Owner or Primary Owner must enable the connector before you can connect Carbon Voice. ## Creating MCP Server - Stand-alone vs Composio SDK The Carbon Voice MCP server connects Claude Web, Desktop, and Cowork to your Carbon Voice account through Composio. Once connected, Claude can use the available Carbon Voice tools and triggers to complete tasks on your behalf. ## Complete Code None listed. ## How to build Carbon Voice MCP Agent with another framework - [ChatGPT](https://composio.dev/toolkits/carbon_voice_mcp/framework/chatgpt) - [Hermes](https://composio.dev/toolkits/carbon_voice_mcp/framework/hermes-agent) ## Related Toolkits - [Gmail](https://composio.dev/toolkits/gmail) - Gmail is Google's email service with powerful spam protection, search, and G Suite integration. It keeps your inbox organized and makes communication fast and reliable. - [Outlook](https://composio.dev/toolkits/outlook) - Outlook is Microsoft's email and calendaring platform for unified communications and scheduling. It helps users stay organized with powerful email, contacts, and calendar management. - [Slack](https://composio.dev/toolkits/slack) - Slack is a channel-based messaging platform for teams and organizations. It helps people collaborate in real time, share files, and connect all their tools in one place. - [Gong](https://composio.dev/toolkits/gong) - Gong is a platform for video meetings, call recording, and team collaboration. It helps teams capture conversations, analyze calls, and turn insights into action. - [Microsoft teams](https://composio.dev/toolkits/microsoft_teams) - Microsoft Teams is a collaboration platform that combines chat, meetings, and file sharing within Microsoft 365. It keeps distributed teams connected and productive through seamless virtual communication. - [Slackbot](https://composio.dev/toolkits/slackbot) - Slackbot is a conversational automation tool for Slack that handles reminders, notifications, and automated responses. It boosts team productivity by streamlining onboarding, answering FAQs, and managing timely alerts—all right inside Slack. - [2chat](https://composio.dev/toolkits/_2chat) - 2chat is an API platform for WhatsApp and multichannel text messaging. It streamlines chat automation, group management, and real-time messaging for developers. - [Agent mail](https://composio.dev/toolkits/agent_mail) - Agent mail provides AI agents with dedicated email inboxes for sending, receiving, and managing emails. It empowers agents to communicate autonomously with people, services, and other agents—no human intervention needed. - [Android Texter](https://composio.dev/toolkits/android_texter) - Android Texter is an API service that connects Android phones to SMS, MMS, contacts, and device data. Use it to automate mobile messaging without building your own phone-to-API bridge. - [Basecamp](https://composio.dev/toolkits/basecamp) - Basecamp is a project management and team collaboration tool by 37signals. It helps teams organize tasks, share files, and communicate efficiently in one place. - [Blooio](https://composio.dev/toolkits/blooio) - Blooio is a stable v2 API platform for messaging, chats, contacts, groups, phone numbers, and account analytics. It gives teams a clean way to build reliable communication workflows without stitching together fragile custom APIs. - [CallOnTheGo](https://composio.dev/toolkits/callonthego) - CallOnTheGo is a telephony API for managing phone numbers, caller IDs, suppression lists, audio assets, contact lists, and Voice AI campaigns. It provides programmatic control over calling infrastructure and campaign automation for scalable voice outreach. - [CardClan](https://composio.dev/toolkits/cardclan) - CardClan is a digital card platform for creating and sending personalized team cards. Use it to celebrate moments, share card links, and manage card workflows without extra coordination. - [Chatwork](https://composio.dev/toolkits/chatwork) - Chatwork is a team communication platform with group chats, file sharing, and task management. It helps businesses boost collaboration and streamline productivity. - [Clickmeeting](https://composio.dev/toolkits/clickmeeting) - ClickMeeting is a cloud-based platform for running online meetings and webinars. It helps businesses and individuals host, manage, and engage virtual audiences with ease. - [Confluence](https://composio.dev/toolkits/confluence) - Confluence is Atlassian's team collaboration and knowledge management platform. It helps your team organize, share, and update documents and project content in one secure workspace. - [Daily](https://composio.dev/toolkits/daily) - Daily is a WebRTC video and audio API platform for building rooms, meetings, recordings, live streams, transcriptions, and telephony. It gives developers reliable real-time media infrastructure without managing complex conferencing stacks. - [Dailybot](https://composio.dev/toolkits/dailybot) - DailyBot streamlines team collaboration with chat-based standups, reminders, and polls. It keeps work flowing smoothly in your favorite messaging platforms. - [Dialmycalls](https://composio.dev/toolkits/dialmycalls) - Dialmycalls is a mass notification service for sending voice and text messages to contacts. It helps teams and organizations quickly broadcast urgent alerts and updates. - [Dialpad](https://composio.dev/toolkits/dialpad) - Dialpad is a cloud-based business phone and contact center system for teams. It unifies voice, video, messaging, and meetings across your devices. ## Frequently Asked Questions ### What are the differences in Tool Router MCP and Carbon Voice MCP? With a standalone Carbon Voice MCP server, the agents and LLMs can only access a fixed set of Carbon Voice tools tied to that server. However, with the Composio Tool Router, agents can dynamically load tools from Carbon Voice and many other apps based on the task at hand, all through a single MCP endpoint. ### Can I use Tool Router MCP with Claude Cowork? Yes, you can. Claude Cowork fully supports MCP integration. You get structured tool calling, message history handling, and model orchestration while Tool Router takes care of discovering and serving the right Carbon Voice tools. ### Can I manage the permissions and scopes for Carbon Voice while using Tool Router? Yes, absolutely. You can configure which Carbon Voice scopes and actions are allowed when connecting your account to Composio. You can also bring your own OAuth credentials or API configuration so you keep full control over what the agent can do. ### How safe is my data with Composio Tool Router? All sensitive data such as tokens, keys, and configuration is fully encrypted at rest and in transit. Composio is SOC 2 Type 2 compliant and follows strict security practices so your Carbon Voice data and credentials are handled as safely as possible. --- [See all toolkits](https://composio.dev/toolkits) · [Composio docs](https://docs.composio.dev/llms.txt)