Update ts docs

Author: agu-z

docs/protocol/schema.mdx

@@ -389,9 +389,19 @@ See protocol docs: [Check for Completion](https://agentclientprotocol.com/protoc
 <a id="session-set_mode"></a>
 ### <span class="font-mono">session/set_mode</span>
 
-**UNSTABLE**
+Sets the current mode for a session.
 
-This method is not part of the spec, and may be removed or changed at any point.
+Allows switching between different agent modes (e.g., "ask", "architect", "code")
+that affect system prompts, tool availability, and permission behaviors.
+
+The mode must be one of the modes advertised in `availableModes` during session
+creation or loading. Agents may also change modes autonomously and notify the
+client via `current_mode_update` notifications.
+
+This method can be called at any time during a session, whether the Agent is
+idle or actively generating a response.
+
+See protocol docs: [Session Modes](https://agentclientprotocol.com/protocol/session-modes)
 
 #### <span class="font-mono">SetSessionModeRequest</span>
 

docs/protocol/session-modes.mdx

@@ -32,7 +32,7 @@ During [Session Setup](./session-setup) the Agent **MAY** return a list of modes
           "id": "code",
           "name": "Code",
           "description": "Write and modify code with full tool access"
-        },
+        }
       ]
     }
   }
@@ -92,7 +92,8 @@ Typically, Clients display the available modes to the user and allow them to cha
 </ParamField>
 
 <ParamField path="modeId" type="SessionModeId" required>
-  The ID of the mode to switch to. Must be one of the modes listed in `availableModes`
+  The ID of the mode to switch to. Must be one of the modes listed in
+  `availableModes`
 </ParamField>
 
 ### From the Agent

rust/acp.rs

@@ -684,7 +684,6 @@ impl<T: Agent> MessageHandler<AgentSide> for T {
                 let response = self.prompt(args).await?;
                 Ok(AgentResponse::PromptResponse(response))
             }
-            #[cfg(feature = "unstable")]
             ClientRequest::SetSessionModeRequest(args) => {
                 let response = self.set_session_mode(args).await?;
                 Ok(AgentResponse::SetSessionModeResponse(response))

rust/example_agent.rs

@@ -112,6 +112,14 @@ impl acp::Agent for ExampleAgent {
         Ok(())
     }
 
+    async fn set_session_mode(
+        &self,
+        args: acp::SetSessionModeRequest,
+    ) -> Result<acp::SetSessionModeResponse, acp::Error> {
+        log::info!("Received set session mode request {args:?}");
+        Ok(Default::default())
+    }
+
     async fn ext_method(
         &self,
         method: std::sync::Arc<str>,

rust/example_client.rs

@@ -97,7 +97,8 @@ impl acp::Client for ExampleClient {
             | acp::SessionUpdate::AgentThoughtChunk { .. }
             | acp::SessionUpdate::ToolCall(_)
             | acp::SessionUpdate::ToolCallUpdate(_)
-            | acp::SessionUpdate::Plan(_) => {}
+            | acp::SessionUpdate::Plan(_)
+            | acp::SessionUpdate::CurrentModeUpdate { .. } => {}
         }
         Ok(())
     }

rust/rpc_tests.rs

@@ -211,7 +211,7 @@ impl Agent for TestAgent {
         &self,
         _arguments: SetSessionModeRequest,
     ) -> Result<SetSessionModeResponse, Error> {
-        Ok(SetSessionModeResponse {})
+        Ok(SetSessionModeResponse { meta: None })
     }
 
     async fn prompt(&self, arguments: PromptRequest) -> Result<PromptResponse, Error> {

typescript/acp.ts

@@ -571,12 +571,19 @@ export class ClientSideConnection implements Agent {
   }
 
   /**
-   * Sets the mode for an existing session.
+   * Sets the operational mode for a session.
    *
-   * This method allows changing the operational mode of an existing session.
-   * The available modes are advertised in the agent's capabilities during initialization.
+   * Allows switching between different agent modes (e.g., "ask", "architect", "code")
+   * that affect system prompts, tool availability, and permission behaviors.
    *
-   * See protocol docs: [Session Mode Management](https://agentclientprotocol.com/protocol/session-management#mode-setting)
+   * The mode must be one of the modes advertised in `availableModes` during session
+   * creation or loading. Agents may also change modes autonomously and notify the
+   * client via `current_mode_update` notifications.
+   *
+   * This method can be called at any time during a session, whether the Agent is
+   * idle or actively generating a turn.
+   *
+   * See protocol docs: [Session Modes](https://agentclientprotocol.com/protocol/session-modes)
    */
   async setSessionMode(
     params: schema.SetSessionModeRequest,
@@ -1239,9 +1246,19 @@ export interface Agent {
     params: schema.LoadSessionRequest,
   ): Promise<schema.LoadSessionResponse>;
   /**
-   * @internal **UNSTABLE**
+   * Sets the operational mode for a session.
+   *
+   * Allows switching between different agent modes (e.g., "ask", "architect", "code")
+   * that affect system prompts, tool availability, and permission behaviors.
+   *
+   * The mode must be one of the modes advertised in `availableModes` during session
+   * creation or loading. Agents may also change modes autonomously and notify the
+   * client via `current_mode_update` notifications.
+   *
+   * This method can be called at any time during a session, whether the Agent is
+   * idle or actively generating a turn.
    *
-   * This method is not part of the spec, and may be removed or changed at any point.
+   * See protocol docs: [Session Modes](https://agentclientprotocol.com/protocol/session-modes)
    */
   setSessionMode?(
     params: schema.SetSessionModeRequest,