# Comms

> Messaging, Calls and Payments API documentation for your Comms workspace.

- [Comms](https://docs.osis.co/index.md): Send messages, handle calls, and take payments from your backend.
- [Quickstart](https://docs.osis.co/quickstart.md): Create an API key and send your first message.
- [Build a two-way integration](https://docs.osis.co/guides/developer-integration.md): The steps to send messages from your backend, get replies with webhooks, and connect an AI tool over MCP.
- [Send an RCS message](https://docs.osis.co/guides/rcs.md): Send a plain-text RCS message from a dedicated phone number.
- [Idempotency](https://docs.osis.co/guides/idempotency.md): Retry requests safely without sending anything twice.
- [Webhooks](https://docs.osis.co/guides/webhooks.md): Get message, call, payment, and contact events sent to your server as they happen.
- [Calls](https://docs.osis.co/guides/calls.md): Place, answer and stream phone and FaceTime calls on your line from your own app.
- [Call forwarding](https://docs.osis.co/guides/call-forwarding.md): Forward incoming cellular calls on your dedicated number to another phone.
- [Connect over MCP](https://docs.osis.co/guides/mcp.md): Connect Claude, Cursor, ChatGPT, or any MCP client to your Comms workspace.
- [Messaging in HighLevel](https://docs.osis.co/guides/highlevel.md): Connect a HighLevel sub-account to a dedicated Comms line.
- [Errors & rate limits](https://docs.osis.co/guides/errors-and-rate-limits.md): What each status code means and how to retry safely.
- [API overview](https://docs.osis.co/messages-api/overview.md): The base URL and the basics that apply to every Comms endpoint.
- [Authentication](https://docs.osis.co/messages-api/authentication.md): API keys, scopes, and how to rotate them.
- [Send a message](https://docs.osis.co/messages-api/send-message.md): Send an iMessage, RCS, WhatsApp, or SMS message from your Comms line.
- [Check messaging capabilities](https://docs.osis.co/messages-api/check-capabilities.md): See if a phone number or email can get iMessage, RCS, or WhatsApp, without sending anything.
- [React to a message](https://docs.osis.co/messages-api/react-to-message.md): Add, change, or remove a reaction on a message.
- [Unsend a message](https://docs.osis.co/messages-api/unsend-message.md): Unsend an iMessage or WhatsApp message you sent.
- [Send a poll](https://docs.osis.co/messages-api/send-poll.md): Send an iMessage or WhatsApp poll.
- [Create a group chat](https://docs.osis.co/messages-api/create-group-chat.md): Start an iMessage or WhatsApp group chat and send the first message.
- [Send a contact card](https://docs.osis.co/messages-api/send-contact-card.md): Text someone a contact card they can save.
- [Set a contact card](https://docs.osis.co/messages-api/set-contact-card.md): Set the name and photo people see for an agent on a dedicated line.
- [List messages](https://docs.osis.co/messages-api/list-messages.md): Read your message history.
- [List conversations](https://docs.osis.co/messages-api/list-conversations.md): List the conversations on your lines.
- [Typing](https://docs.osis.co/messages-api/typing.md): Show or hide the typing indicator in a conversation.
- [Set a chat backdrop](https://docs.osis.co/messages-api/chat-backdrop.md): Set or clear the background of an iMessage conversation.
- [Mark conversation read](https://docs.osis.co/messages-api/mark-conversation-read.md): Mark an iMessage, RCS, or WhatsApp conversation as read.
- [Read a shared location](https://docs.osis.co/messages-api/shared-location.md): Read a location a contact is sharing with your dedicated number.
- [List available lines](https://docs.osis.co/messages-api/list-available-lines.md): See which dedicated numbers you can claim.
- [Claim a line](https://docs.osis.co/messages-api/claim-line.md): Add a dedicated number to your workspace.
- [Line porting](https://docs.osis.co/messages-api/line-porting.md): Bring your existing phone number to a Comms dedicated line.
- [Prepare a line for porting](https://docs.osis.co/messages-api/lock-line.md): Prepare a dedicated line to receive your existing number. Cancel any time before you submit the port.
- [Submit a port](https://docs.osis.co/messages-api/start-line-port.md): Send your carrier details to port your number to a prepared line.
- [Get port status](https://docs.osis.co/messages-api/get-line-port.md): Check how your number port is going.
- [Change a phone number](https://docs.osis.co/messages-api/change-number.md): Get a new number for an existing dedicated line.
- [Calls API overview](https://docs.osis.co/calls-api/overview.md): Place, answer and control phone and FaceTime calls on your lines.
- [List calls](https://docs.osis.co/calls-api/list-calls.md): List calls on your lines, newest first.
- [Place a call](https://docs.osis.co/calls-api/place-call.md): Call a phone number from one of your lines, as a cellular call or FaceTime audio.
- [Get a call](https://docs.osis.co/calls-api/get-call.md): Read one call by its ID.
- [Answer a call](https://docs.osis.co/calls-api/answer-call.md): Pick up a call that's ringing on your line.
- [Decline a call](https://docs.osis.co/calls-api/decline-call.md): Turn away a call that's ringing on your line.
- [Hang up a call](https://docs.osis.co/calls-api/hangup-call.md): End a live call.
- [Speak text on a call (TTS)](https://docs.osis.co/calls-api/say-on-call.md): Send text that Comms speaks to the other party with text-to-speech (TTS). For two-way live audio, use relay mode.
- [Send keypad tones](https://docs.osis.co/calls-api/send-dtmf.md): Press keypad digits (DTMF) on a live call, where the line supports it.
- [List transcript turns](https://docs.osis.co/calls-api/list-call-turns.md): Read what each side said on a call.
- [Get a call's audio session](https://docs.osis.co/calls-api/get-call-media.md): Get the WebSocket address and short-lived token for a relay call's live audio.
- [Download a voicemail](https://docs.osis.co/calls-api/download-voicemail.md): Download the recording a caller left on a missed call.
- [Get call forwarding](https://docs.osis.co/calls-api/get-call-forwarding.md): Read where incoming cellular calls on a dedicated number are forwarded.
- [Set call forwarding](https://docs.osis.co/calls-api/set-call-forwarding.md): Forward incoming cellular calls on a dedicated number to another phone, or turn forwarding off.
- [List webhooks](https://docs.osis.co/messages-api/list-webhooks.md): List your webhooks.
- [Create a webhook](https://docs.osis.co/messages-api/create-webhook.md): Get Comms events sent to your server.
- [List webhook deliveries](https://docs.osis.co/messages-api/list-events.md): See recent webhook deliveries to your endpoints and whether they succeeded.
- [AI usage](https://docs.osis.co/messages-api/ai-usage.md): Check your Comms AI credit balance and billing mode.
- [Payments](https://docs.osis.co/payments-api/overview.md): Connect an account, send a payment request, confirm payment.
- [Hosted agent setup](https://docs.osis.co/payments-api/hosted-agents.md): Let a Comms agent find products, send payment requests, and check payment.
- [Create a payment request](https://docs.osis.co/payments-api/create-payment-request.md): One endpoint for Shopify and both Whop account types.
- [Confirm a payment](https://docs.osis.co/payments-api/payment-confirmation.md): Read a payment request or listen for a verified payment event.
- [Accept merchant terms](https://docs.osis.co/payments-api/accept-merchant-terms.md): Accept the merchant terms to turn on the Payments API.
- [Get merchant status](https://docs.osis.co/payments-api/merchant-status.md): See whether payments are on and which accounts are connected.
- [List payment requests](https://docs.osis.co/payments-api/list-payment-requests.md): List the most recent payment requests in your workspace.
- [Get a payment request](https://docs.osis.co/payments-api/get-payment-request.md): Check a payment request and whether it's been paid.
- [Cancel a payment request](https://docs.osis.co/payments-api/cancel-payment-request.md): Cancel a pending payment request.
- [Connect Shopify](https://docs.osis.co/payments-api/connect-shopify.md): Install the Comms app on your Shopify store.
- [Connect Whop](https://docs.osis.co/payments-api/connect-whop.md): Take payments through Whop, with your own account or one Comms manages.
- [Checkout card branding](https://docs.osis.co/payments-api/branding.md): Put your store's name and image on checkout cards.
- [Read Shopify catalog](https://docs.osis.co/payments-api/shopify-catalog.md): List the products and variants you can sell through checkout.

## OpenAPI Specs

- [openapi](/openapi.json)


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