API Reference

Messages

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Send a message

POST/v1/chats/{chatID}/messages

Send a text message to a specific chat. Supports replying to existing messages. Returns a pending message ID.

Path ParametersExpand Collapse

chatID: string

Chat ID. Input routes also accept the local chat ID from this installation when available.

Body ParametersJSONExpand Collapse

attachment: optional object { uploadID, duration, fileName, 3 more }

Single attachment to send with the message

uploadID: string

Upload ID from uploadAsset endpoint. Required to reference uploaded files.

duration: optional number

Duration in seconds (optional override of cached value)

fileName: optional string

Filename (optional override of cached value)

mimeType: optional string

MIME type (optional override of cached value)

size: optional object { height, width }

Dimensions (optional override of cached value)

height: number

width: number

type: optional "image" or "video" or "audio" or 4 more

Attachment type hint (image, video, audio, file, gif, voice-note, sticker). If omitted, auto-detected from mimeType

One of the following:

"image"

"video"

"audio"

"file"

"gif"

"voice-note"

"sticker"

replyToMessageID: optional string

Provide a message ID to send this as a reply to an existing message

text: optional string

Draft text. Plain text and Markdown are converted to Beeper rich text with the same rules used by send and edit.

ReturnsExpand Collapse

chatID: string

Chat ID. Input routes also accept the local chat ID from this installation when available.

pendingMessageID: string

Pending ID assigned to the message before the network confirms the send. Pass it to GET /v1/chats/{chatID}/messages/{messageID} to resolve, or wait for the matching message.upserted over the WebSocket.

Send a message

HTTP

HTTP

TypeScript

Python

Go

CLI Tool

PHP

curl http://localhost:23373/v1/chats/$CHAT_ID/messages \
    -X POST \
    -H "Authorization: Bearer $BEEPER_ACCESS_TOKEN"

200 example

{
  "chatID": "!whatsapp_15550101002:ba_EvYDBBsZbRQAy3UOSWqG0LuTVkc.local-whatsapp.localhost",
  "pendingMessageID": "m1694783291234567"
}

Returns Examples

200 example

{
  "chatID": "!whatsapp_15550101002:ba_EvYDBBsZbRQAy3UOSWqG0LuTVkc.local-whatsapp.localhost",
  "pendingMessageID": "m1694783291234567"
}