> ## Documentation Index
> Fetch the complete documentation index at: https://docs.stmlink.com/llms.txt
> Use this file to discover all available pages before exploring further.

> ## Agent Instructions
> 对外开放的服务端接口有两组前缀，都用同一套鉴权：`/server/v1/...`（SRTC 与 SMeeting 的主接口）和 `/stm/srvapi/v1/...`（SMeeting 的用户体系，服务端极简对接会用到）。鉴权是 app_id + nonce + timestamp + signature 四个请求头，用 app_key 做 HMAC-SHA256 签名，只能从业务方自己的后端调用。除这两组前缀外的接口均为内部接口，不要建议客户调用。 Public server APIs use two path prefixes with the same authentication: `/server/v1/...` (the main APIs of both SRTC and SMeeting) and `/stm/srvapi/v1/...` (the SMeeting user system, used by server-side low-code integration). Authenticate with four request headers, app_id + nonce + timestamp + signature, where signature is HMAC-SHA256 keyed with app_key; call these APIs only from the customer's own backend. Any other path is internal: never suggest calling it.
> app_key 是服务端密钥，绝不能出现在客户端代码、前端配置或移动 App 里。客户端加入频道用的 token 必须由业务方后端签发后下发（SRTC 走 `/server/v1/channel/grant`，SMeeting 走 `/stm/srvapi/v1/member/grant`）。 app_key is a server-side secret and must never appear in client code, frontend config, or a mobile app. The token a client uses to join must be issued by the customer's backend and passed down to the client (SRTC: `/server/v1/channel/grant`; SMeeting: `/stm/srvapi/v1/member/grant`).
> SRTC 与 SMeeting 是上下两层不同的产品，术语不通用：SRTC 是音视频底座，说「频道 channel」「加入 / 退出」；SMeeting 建在 SRTC 之上，说「房间 room」「会议 meeting」「进入 / 退出」。回答时按用户所在的层用对应术语，不要把「房间」「会议」安到 SRTC 的接口上，也不要用「频道」「加入 / 离开」描述 SMeeting 的概念（接口标识符原样保留）。 SRTC and SMeeting are two separate layers with different terminology. SRTC is the audio/video foundation: it has channels, and users join and leave a channel. SMeeting is built on top of SRTC: it has rooms and meetings, and members enter and exit a meeting. Answer in the terms of the layer the user is working with: never apply "room" or "meeting" to SRTC APIs, and never describe SMeeting concepts in prose with "channel", "join", or "leave" (API identifiers such as `force_join` keep their literal names).
> 同一能力在各端 SDK 里的包名、类名、方法名并不相同。写示例代码时请使用文档中该端自己的 API，不要把一个端的写法套到另一个端上。苹果平台每个产品都有两套 SDK（Swift 原生与 Objective-C），两套 API 不能混用。 Package, class, and method names differ between platform SDKs for the same capability. In sample code, use the API documented for that platform; never carry one platform's code over to another. On Apple platforms each product ships two SDKs (native Swift and Objective-C) whose APIs must not be mixed.

# MeetingKitIMDelegate

> Callback protocol of the iOS SMeeting SDK's out-of-meeting message path (IM): connection state, incoming calls, meeting reminders, being admitted from the waiting room, and sub-meeting help requests. Read this after calling enableImWithDelegate:.

## Connection callbacks

### onImConnectSucceed:sessionId:()

`- (void)onImConnectSucceed:(NSString *)userId sessionId:(NSString *)sessionId`

Called when the connection succeeds.

After you call `enableImWithDelegate:()` to enable IM, you receive this notification once the connection succeeds. If an error occurs, the SDK fires the `onImDisconnected:errCode:errMsg:()` callback.

**Parameters**

| userId | User ID |
| - | - |
| sessionId | Session ID |

### onImReconnecting()

`- (void)onImReconnecting`

Called when reconnection starts.

Fires when the connection drops and reconnection starts. If an error occurs, the SDK fires the `onImDisconnected:errCode:errMsg:()` callback.

### onImReconnected()

`- (void)onImReconnected`

Called when reconnection succeeds.

Fires after reconnecting successfully following a disconnect. If an error occurs, the SDK fires the `onImDisconnected:errCode:errMsg:()` callback.

### onImDisconnected:errCode:errMsg:()

`- (void)onImDisconnected:(SEAImDisconnectReason)reason errCode:(SEAError)errCode errMsg:(nullable NSString *)errMsg`

Called when the connection drops or you're passively disconnected.

When the disconnect reason is `SEAImDisconnectReasonError`, the SDK has hit an unrecoverable error, such as an authentication failure. In this case you must get a new token before you can enable IM again. For the error codes, see [Error codes](/en/meeting/ios/error-codes).

When the disconnect reason is anything other than `SEAImDisconnectReasonError`, the connection was dropped passively. For the specific reasons, see [Disconnect reasons](/en/meeting/ios/types#seaimdisconnectreason).

**Parameters**

| reason | Disconnect reason |
| - | - |
| errCode | Error code |
| errMsg | Error message |

## Message callbacks

### onImMessage:action:userId:sessionId:nickname:()

`- (void)onImMessage:(NSString *)content action:(NSString *)action userId:(nullable NSString *)userId sessionId:(nullable NSString *)sessionId nickname:(nullable NSString *)nickname`

Called when a message is received.

When your app's business features send a message event through the backend API, the SDK notifies you through this callback.

**Parameters**

| content | Message content |
| - | - |
| action | Message identifier |
| userId | User ID |
| sessionId | Session ID |
| nickname | User nickname |

### onMeetingRemind:()

`- (void)onMeetingRemind:(SEAMeetingRemindModel *)remindModel`

Called when a meeting is about to start.

When a scheduled meeting you need to attend is about to start, the SDK notifies you through this callback.

**Parameters**

| remindModel | Meeting reminder content. For details, see [SEAMeetingRemindModel](/en/meeting/ios/types#seameetingremindmodel) |
| - | - |

## Call callbacks

### onCallReceived:nickname:roomNo:title:()

`- (void)onCallReceived:(NSString *)callerId nickname:(nullable NSString *)nickname roomNo:(NSString *)roomNo title:(NSString *)title`

Called when a call request arrives.

When the host calls you through the call API, the SDK notifies you through this callback. Listen for this event to decide whether to show the call answering UI.

**Parameters**

| callerId | Caller ID |
| - | - |
| nickname | Caller nickname |
| roomNo | Room number |
| title | Meeting title |

## Waiting room callbacks

### onWaitingRoomMoveInRoom:title:()

`- (void)onWaitingRoomMoveInRoom:(NSString *)meetingId title:(nullable NSString *)title`

Called when the host or a co-host admits you from the waiting room into the meeting.

When the host moves people from the waiting room into the meeting, the SDK notifies you through this callback. Listen for this event to decide whether to enter the meeting right away.

**Parameters**

| meetingId | Meeting ID |
| - | - |
| title | Meeting title |

## Sub-meeting callbacks

### onSubMettingAskingHelp:meetingId:title:()

`- (void)onSubMettingAskingHelp:(NSString *)parentMid meetingId:(NSString *)meetingId title:(nullable NSString *)title`

Called when a sub-meeting asks for help.

When members of a sub-meeting ask for help, the SDK notifies the host and co-hosts of the main meeting through this callback. Listen for this event to decide whether to handle the help request.

**Parameters**

| parentMid | Parent meeting ID |
| - | - |
| meetingId | Sub-meeting ID |
| title | Sub-meeting title |