Updated from Slack docs, 2026/04/13

Author: Slack API Ref Buildbot

docs.slack.dev/methods/assistant.threads.setStatus.json

@@ -47,6 +47,21 @@
           "minLength": 1,
           "maxLength": 50
         }
+      },
+      "icon_emoji": {
+        "type": "string",
+        "desc": "Emoji to use as the icon for this message. Overrides `icon_url`.",
+        "example": ":chart_with_upwards_trend:"
+      },
+      "icon_url": {
+        "type": "string",
+        "desc": "Image URL to use as the icon for this message.",
+        "example": "http://lorempixel.com/48/48"
+      },
+      "username": {
+        "type": "string",
+        "desc": "The bot's username to display.",
+        "example": "My Bot"
       }
     }
   },

docs.slack.dev/methods/chat.startStream.json

@@ -64,6 +64,21 @@
         ],
         "default": "timeline",
         "example": "plan"
+      },
+      "icon_emoji": {
+        "type": "string",
+        "desc": "Emoji to use as the icon for this message. Overrides `icon_url`.",
+        "example": ":chart_with_upwards_trend:"
+      },
+      "icon_url": {
+        "type": "string",
+        "desc": "Image URL to use as the icon for this message.",
+        "example": "http://lorempixel.com/48/48"
+      },
+      "username": {
+        "type": "string",
+        "desc": "The bot's username to display.",
+        "example": "My Bot"
       }
     }
   },

methods/assistant/assistant.threads.setStatus.json

@@ -23,6 +23,24 @@
       "required": false,
       "desc": "The list of messages to rotate through as a loading indicator. Maximum of 10 messages.",
       "type": "array"
+    },
+    "icon_emoji": {
+      "required": false,
+      "example": ":chart_with_upwards_trend:",
+      "desc": "Emoji to use as the icon for this message. Overrides icon_url.",
+      "type": "string"
+    },
+    "icon_url": {
+      "required": false,
+      "example": "http://lorempixel.com/48/48",
+      "desc": "Image URL to use as the icon for this message.",
+      "type": "string"
+    },
+    "username": {
+      "required": false,
+      "example": "My Bot",
+      "desc": "The bot's username to display.",
+      "type": "string"
     }
   },
   "response": {

methods/chat/chat.startStream.json

@@ -41,6 +41,24 @@
       "example": "plan",
       "desc": "Specifies how tasks are displayed in the message. A timeline displays individual tasks with text in sequential order, and plan displays all tasks together, with the first tasks's placement determining the placement of the rest of the tasks.",
       "type": "enum"
+    },
+    "icon_emoji": {
+      "required": false,
+      "example": ":chart_with_upwards_trend:",
+      "desc": "Emoji to use as the icon for this message. Overrides icon_url.",
+      "type": "string"
+    },
+    "icon_url": {
+      "required": false,
+      "example": "http://lorempixel.com/48/48",
+      "desc": "Image URL to use as the icon for this message.",
+      "type": "string"
+    },
+    "username": {
+      "required": false,
+      "example": "My Bot",
+      "desc": "The bot's username to display.",
+      "type": "string"
     }
   },
   "response": {