Sending and Receiving Activities

Every activity contains information used for routing the activity to the appropriate destination. Bots receive activities from the user and send them back, just like people exchange messages.

Routing Activities

Activities have properties which enable the connector service to deliver to the proper recipient, communicating who created the message, the context of the message and the recipient of the message.

The Connector service models this as From -> Recipient as part of a Conversation.

Property Description
From Sender of the activity
Recipient Recipient of the activity
Conversation Conversation the message was part of

When you receive a Activity from a user it will have the From field set to the user who created the message and the Recipient field will always be your bot's identity in that conversation.

NOTE: a bot doesn't always know it's identity because some channels assign new identities when the bot is added to a conversation. (e.g. Slack) As a result, it is important when you are create a reply message you use the incoming Recipient property as the outgoing From. (see Replying to an Activity for more details).

ChannelId and ServiceUrl

There are 2 top level properties which tell the bot what channel it is working with and the url that should be used for API operations like sending a reply.

Property Description Examples
ChannelId The channel for the activity skype
ServiceUrl The url to use for sending activities back

Creating Connector Client

The ServiceUrl provides the appropriate endpoint for API calls. All you have to do is pass it into the constructor of the ConnectorClient() class.

var connector = new ConnectorClient(incomingMessage.ServiceUrl);

NOTE: Even though ServiceUrl values may seem stable bots should not rely on that and instead always use the ServiceUrl value


The ChannelAccount record is used to represent an address a user or bot on a communication channel.

Property Description Examples
Id The address on the channel joe .com, +14258828080, etc.
Name A name for the user or bot Joe Smith

Each user has 1..N ChannelAccounts which represent their identities on each channel.

Each bot has 1..N ChannelAccounts which represent their identities on each channel.


The ConversationAccount object is basically the same as a ChannelAccount with some additional metadata.

Property Description Examples
Id A unique id for the conversation on the channel Xy1xvh3jhv
Name A name for the conversation Fantasy football
IsGroup if true, indicates a group conversation (default is false) bool

Replying to messages

When your bot receives a message Activity it will want to respond.

To do that, you need a new Activity() with

  • The From <–> Recipient fields swapped from the original message(so that it will be routed back to where it came from using the identify for your bot in that conversation)
  • The Conversation from the original message on it (route to the same conversation)
  • Text (and Attachments as appropriate)

To make this easy to do we have an extension method on the Activity class called CreateReply().

To create a reply message for an existing incoming activity:

// create properly formatted reply message
var replyMessage = incomingMessage.CreateReply("Yo, what's up?");


To reply simply create a reply message and call the ReplyToActivity() method. The Connector service will take care of the details of delivering your message using the appropriate channel semantics.

var connector = new ConnectorClient(incomingMessage.ServiceUrl);
var replyMessage = incomingMessage.CreateReply("Yo, I heard you.", "en");
await connector.Conversations.ReplyToActivityAsync(replyMessage);


The SendToConversation() method is almost identical to ReplyToActivity() except that it doesn't maintain any sort of threading. It is used when don't have an activity to reply to. If you do have an activity to reply to you should us the ReplyToActivity() method.

var connector = new ConnectorClient(incomingMessage.ServiceUrl);
IMessageActivity newMessage = Activity.CreateMessageActivity();
newMessage.Type = ActivityTypes.Message;
newMessage.From = botAccount;
newMessage.Conversation = conversation;
newMessage.Recipient = userAccount;
newMessage.Text = "Yo yo yo!";
await connector.Conversations.SendToConversationAsync((Activity)newMessage);

Multiple replies

It is perfectly fine to send as many messages you want via these methods.

var connector = new ConnectorClient(incomingMessage.ServiceUrl);
connector.Conversations.ReplyToActivity(incomingMessage.CreateReply("Yo, I heard you 1.", "en"));
connector.Conversations.ReplyToActivity(incomingMessage.CreateReply("Yo, I heard you 2.", "en"));
connector.Conversations.ReplyToActivity(incomingMessage.CreateReply("Yo, I heard you 3.", "en"));

NOTE: Most channels have built in throttling levels and you will be subject to whatever limits the channel sets.

Starting Conversations

To initiate a conversation you need to call the CreateConversation() or CreateDirectConversation() methods to get a ConversationAccount record from the channel. Once you have the ConversationAccount can use it in a message call to SendToConversation().

Create 1:1 Conversations

The CreateDirectConversation() method is used to create a private 1:1 conversation between the bot and the user.

To initialize a ConnectorClient you use ServiceUrl persisted from previous messages.


var userAccount = new ChannelAccount(name: "Larry", id: "@UV357341");
var connector = new ConnectorClient(new Uri(incomingMessage.ServiceUrl));
var conversationId = await connector.Conversations.CreateDirectConversationAsync(botAccount, userAccount);
IMessageActivity message = Activity.CreateMessageActivity();
message.From = botAccount;
message.Recipient = userAccount;
message.Conversation = new ConversationAccount(id: conversationId.Id);
message.Text = "Hello";
message.Locale = "en-Us";
await connector.Conversations.SendToConversationAsync((Activity)message);

Create Group Conversations

The CreateConversation() method is used to create a new group conversation.

NOTE: Currently Email is the only channel which supports bot initiated group conversations


var connector = new ConnectorClient(new Uri(incomingMessage.ServiceUrl));
List<ChannelAccount> participants = new List<ChannelAccount>();
participants.Add(new ChannelAccount("", "Joe the Engineer"));
participants.Add(new ChannelAccount("", "Sara in Finance"));
ConversationParameters cpMessage = new ConversationParameters(message.Recipient, true, participants, "Quarter End Discussion");
var conversationId = await connector.Conversations.CreateConversationAsync(cpMessage);
IMessageActivity message = Activity.CreateMessageActivity();
message.From = botAccount;
message.Recipient = new ChannelAccount("", "Lydia the CFO"));
message.Conversation = new ConversationAccount(id: conversationId.Id);
message.ChannelId = incomingMessage.ChannelId;
message.Text = "Hey, what's up everyone?";
message.Locale = "en-Us";
await connector.Conversations.SendToConversationAsync((Activity)message);