WhatsApp Gateway
API referenceGroups

Add members to a group

Adds the listed **participants** (user JIDs) to the group. **Capability:** requires `send`. **Precondition (live action):** the session must be **connected** and its account must be a group **admin**. If the session is not connected the gateway responds **501 `not_implemented`**. **Success:** **204 No Content** (empty body). **Notes:** WhatsApp may decline to add some numbers (privacy settings, invalid number) without failing the whole call. Adding a JID that is already a member is a no-op. **Errors:** - **400 `validation_error`** — empty participant list or a malformed JID. - **404 `not_found`** — the session or group does not exist (or is not yours). - **403 `forbidden`** — the session's account is not an admin of this group. - **501 `not_implemented`** — the session is not connected.

POST
/api/v1/sessions/{session}/groups/{gid}/members

Authorization

AuthorizationBearer <token>

Send Authorization: Bearer <token>. The router accepts two kinds of token and tries each in turn: a frontend-minted login JWT (verified against the frontend JWKS; the person's org + role are read from it), or an api-key for a script/service (carrying a fixed set of gateway permissions). The bearerFormat: JWT label describes the person-login case.

In: header

Path Parameters

session*string

The WhatsApp session id that owns the group; must be connected for this live action.

gid*string

The group's JID, ending in @g.us. Percent-encode the @ as %40 in the URL path; the gateway URL-decodes it.

Request Body

application/json

TypeScript Definitions

Use the request body type in TypeScript.

participants?array<string>|

User JIDs to add to the group (each ending in @s.whatsapp.net). Required by the service. The session's account must be a group admin; some numbers may decline to be added depending on their privacy settings.

Response Body

application/json

curl -X POST "https://example.com/api/v1/sessions/01HZ0SESSION0000000000000/groups/120363041234567890@g.us/members" \  -H "Content-Type: application/json" \  -d '{}'
Empty
{  "error": {    "code": "not_found",    "details": {      "property1": null,      "property2": null    },    "message": "session not found"  }}