diff --git a/crates/goose-server/src/routes/reply.rs b/crates/goose-server/src/routes/reply.rs
index df33fd2ea4..0cc40535eb 100644
--- a/crates/goose-server/src/routes/reply.rs
+++ b/crates/goose-server/src/routes/reply.rs
@@ -79,8 +79,11 @@ fn track_tool_telemetry(content: &MessageContent, all_messages: &[Message]) {
 #[derive(Debug, Deserialize, Serialize, utoipa::ToSchema)]
 pub struct ChatRequest {
     user_message: Message,
+    /// Override the server's conversation history. Only use this when you need absolute control
+    /// over the conversation state (e.g., administrative tools). For normal operations, the server
+    /// is the source of truth - use truncate/fork endpoints to modify conversation history instead.
     #[serde(default)]
-    conversation_so_far: Option<Vec<Message>>,
+    override_conversation: Option<Vec<Message>>,
     session_id: String,
     recipe_name: Option<String>,
     recipe_version: Option<String>,
@@ -240,7 +243,7 @@ pub async fn reply(
     let cancel_token = CancellationToken::new();
 
     let user_message = request.user_message;
-    let conversation_so_far = request.conversation_so_far;
+    let override_conversation = request.override_conversation;
 
     let task_cancel = cancel_token.clone();
     let task_tx = tx.clone();
@@ -285,7 +288,7 @@ pub async fn reply(
             retry_config: None,
         };
 
-        let mut all_messages = match conversation_so_far {
+        let mut all_messages = match override_conversation {
             Some(history) => {
                 let conv = Conversation::new_unvalidated(history);
                 if let Err(e) = state
@@ -489,7 +492,7 @@ mod tests {
                 .body(Body::from(
                     serde_json::to_string(&ChatRequest {
                         user_message: Message::user().with_text("test message"),
-                        conversation_so_far: None,
+                        override_conversation: None,
                         session_id: "test-session".to_string(),
                         recipe_name: None,
                         recipe_version: None,
diff --git a/ui/desktop/openapi.json b/ui/desktop/openapi.json
index 5ff80c10a4..832bd713af 100644
--- a/ui/desktop/openapi.json
+++ b/ui/desktop/openapi.json
@@ -3898,11 +3898,12 @@
           "session_id"
         ],
         "properties": {
-          "conversation_so_far": {
+          "override_conversation": {
             "type": "array",
             "items": {
               "$ref": "#/components/schemas/Message"
             },
+            "description": "Override the server's conversation history. Only use this when you need absolute control\nover the conversation state (e.g., administrative tools). For normal operations, the server\nis the source of truth - use truncate/fork endpoints to modify conversation history instead.",
             "nullable": true
           },
           "recipe_name": {
diff --git a/ui/desktop/src/api/types.gen.ts b/ui/desktop/src/api/types.gen.ts
index 98ce500928..93e1677293 100644
--- a/ui/desktop/src/api/types.gen.ts
+++ b/ui/desktop/src/api/types.gen.ts
@@ -60,7 +60,12 @@ export type CallToolResponse = {
 };
 
 export type ChatRequest = {
-    conversation_so_far?: Array<Message> | null;
+    /**
+     * Override the server's conversation history. Only use this when you need absolute control
+     * over the conversation state (e.g., administrative tools). For normal operations, the server
+     * is the source of truth - use truncate/fork endpoints to modify conversation history instead.
+     */
+    override_conversation?: Array<Message> | null;
     recipe_name?: string | null;
     recipe_version?: string | null;
     session_id: string;
diff --git a/ui/desktop/src/hooks/useChatStream.ts b/ui/desktop/src/hooks/useChatStream.ts
index ef78641c77..c4732fbec0 100644
--- a/ui/desktop/src/hooks/useChatStream.ts
+++ b/ui/desktop/src/hooks/useChatStream.ts
@@ -590,7 +590,6 @@ export function useChatStream({
           body: {
             session_id: sessionId,
             user_message: newMessage,
-            ...(hasExistingMessages && { conversation_so_far: currentState.messages }),
           },
           throwOnError: true,
           signal: abortControllerRef.current.signal,
@@ -771,7 +770,6 @@ export function useChatStream({
                 body: {
                   session_id: targetSessionId,
                   user_message: updatedUserMessage,
-                  conversation_so_far: truncatedMessages,
                 },
                 throwOnError: true,
                 signal: abortControllerRef.current.signal,