From 849b6f2ae84c2f8c0a8d90df3b29fafb1728d759 Mon Sep 17 00:00:00 2001
From: Lifei Zhou <lifei@squareup.com>
Date: Thu, 13 Aug 2026 09:28:59 +0000
Subject: [PATCH] fix(acp): return authe error for acp provider from goose acp
 server (#11202)

---
 .../src/conversation/message.rs               | 18 +++-
 crates/goose/src/acp/mod.rs                   | 29 ++++++
 crates/goose/src/acp/provider.rs              | 88 +++++++++++++++++--
 crates/goose/src/acp/server.rs                | 54 +++++++++++-
 crates/goose/src/agents/agent.rs              | 56 ++++++++++--
 crates/goose/src/execution/manager.rs         |  7 +-
 crates/goose/src/gateway/handler.rs           | 19 +++-
 .../__tests__/chatSessionController.test.ts   | 15 ++++
 .../acp/__tests__/chatSessionStore.test.ts    | 10 +--
 ui/desktop/src/acp/__tests__/errors.test.ts   | 11 ++-
 ui/desktop/src/acp/chatSessionController.ts   | 17 ++--
 ui/desktop/src/acp/chatSessionStore.ts        |  6 +-
 ui/desktop/src/acp/errors.ts                  | 11 +++
 ui/desktop/src/components/BaseChat.tsx        | 22 +++--
 ui/desktop/src/components/ChatInput.tsx       |  5 +-
 ui/desktop/src/components/Hub.tsx             |  3 +
 ui/desktop/src/hooks/useChatSession.ts        | 18 ++--
 ui/desktop/src/hooks/useChatSessionTypes.ts   |  1 +
 ui/desktop/src/i18n/messages/de.json          |  3 +
 ui/desktop/src/i18n/messages/en.json          |  3 +
 ui/desktop/src/i18n/messages/es.json          |  3 +
 ui/desktop/src/i18n/messages/fr.json          |  3 +
 ui/desktop/src/i18n/messages/hi.json          |  3 +
 ui/desktop/src/i18n/messages/id.json          |  3 +
 ui/desktop/src/i18n/messages/it.json          |  3 +
 ui/desktop/src/i18n/messages/ja.json          |  3 +
 ui/desktop/src/i18n/messages/ko.json          |  3 +
 ui/desktop/src/i18n/messages/ms.json          |  3 +
 ui/desktop/src/i18n/messages/pt.json          |  3 +
 ui/desktop/src/i18n/messages/ru.json          |  3 +
 ui/desktop/src/i18n/messages/tr.json          |  3 +
 ui/desktop/src/i18n/messages/vi.json          |  3 +
 ui/desktop/src/i18n/messages/zh-CN.json       |  3 +
 ui/desktop/src/i18n/messages/zh-TW.json       |  3 +
 34 files changed, 380 insertions(+), 58 deletions(-)

diff --git a/crates/goose-provider-types/src/conversation/message.rs b/crates/goose-provider-types/src/conversation/message.rs
index 13523f021..996ae6e63 100644
--- a/crates/goose-provider-types/src/conversation/message.rs
+++ b/crates/goose-provider-types/src/conversation/message.rs
@@ -262,6 +262,7 @@ pub struct SystemNotificationContent {
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
 #[serde(rename_all = "camelCase")]
 pub enum MessageErrorKind {
+    Authentication,
     ContextLengthExceeded,
     CreditsExhausted,
     #[serde(other)]
@@ -272,6 +273,7 @@ impl From<&crate::errors::ProviderError> for MessageErrorKind {
     fn from(err: &crate::errors::ProviderError) -> Self {
         use crate::errors::ProviderError;
         match err {
+            ProviderError::Authentication(_) => MessageErrorKind::Authentication,
             ProviderError::ContextLengthExceeded(_) => MessageErrorKind::ContextLengthExceeded,
             ProviderError::CreditsExhausted { .. } => MessageErrorKind::CreditsExhausted,
             _ => MessageErrorKind::Other,
@@ -1320,9 +1322,10 @@ pub struct TokenState {
 #[cfg(test)]
 mod tests {
     use crate::conversation::message::{
-        ActionRequiredData, Message, MessageContentBlock, MessageMetadata, ProviderMetadata,
-        ToolResponse,
+        ActionRequiredData, Message, MessageContentBlock, MessageErrorKind, MessageMetadata,
+        ProviderMetadata, ToolResponse,
     };
+    use crate::errors::ProviderError;
     use base64::Engine;
     use rmcp::model::{
         Annotations, CallToolResult, ElicitationAction, ErrorCode, ErrorData, ImageContent,
@@ -1332,6 +1335,17 @@ mod tests {
     use rmcp::object;
     use serde_json::Value;
 
+    #[test]
+    fn provider_authentication_error_has_authentication_kind() {
+        let message = Message::from_provider_error(&ProviderError::Authentication(
+            "Authentication required".to_string(),
+        ));
+
+        assert_eq!(message.error_kind(), Some(MessageErrorKind::Authentication));
+        assert!(message.is_user_visible());
+        assert!(!message.is_agent_visible());
+    }
+
     #[test]
     fn test_sanitize_with_text() {
         let malicious = "Hello\u{E0041}\u{E0042}\u{E0043}world"; // Invisible "ABC"
diff --git a/crates/goose/src/acp/mod.rs b/crates/goose/src/acp/mod.rs
index bba5e9dea..1e4283062 100644
--- a/crates/goose/src/acp/mod.rs
+++ b/crates/goose/src/acp/mod.rs
@@ -14,3 +14,32 @@ pub use goose_sdk_types::{custom_notifications, custom_requests};
 pub use provider::{
     resolve_extension_configs_to_mcp_servers, AcpProvider, AcpProviderConfig, ACP_CURRENT_MODEL,
 };
+
+pub(crate) fn is_auth_required(error: &anyhow::Error) -> bool {
+    error.chain().any(|source| {
+        source
+            .downcast_ref::<agent_client_protocol::Error>()
+            .is_some_and(|error| {
+                error.code == agent_client_protocol::schema::v1::ErrorCode::AuthRequired
+            })
+    })
+}
+
+#[cfg(test)]
+mod tests {
+    use super::is_auth_required;
+
+    #[test]
+    fn identifies_typed_auth_required_errors() {
+        let error = anyhow::Error::new(agent_client_protocol::Error::auth_required());
+
+        assert!(is_auth_required(&error));
+    }
+
+    #[test]
+    fn does_not_classify_other_acp_errors_as_authentication() {
+        let error = anyhow::Error::new(agent_client_protocol::Error::internal_error());
+
+        assert!(!is_auth_required(&error));
+    }
+}
diff --git a/crates/goose/src/acp/provider.rs b/crates/goose/src/acp/provider.rs
index 0f1c98586..d884d7d71 100644
--- a/crates/goose/src/acp/provider.rs
+++ b/crates/goose/src/acp/provider.rs
@@ -126,7 +126,15 @@ enum AcpUpdate {
         response_tx: oneshot::Sender<RequestPermissionResponse>,
     },
     Complete(StopReason, Option<AcpUsage>),
-    Error(String),
+    Error(agent_client_protocol::Error),
+}
+
+fn provider_error_from_acp(error: agent_client_protocol::Error) -> ProviderError {
+    if error.code == agent_client_protocol::schema::v1::ErrorCode::AuthRequired {
+        ProviderError::Authentication(error.to_string())
+    } else {
+        ProviderError::RequestFailed(error.to_string())
+    }
 }
 
 /// Per-tool-call buffer for accumulating ACP ToolCallUpdate fields across
@@ -723,7 +731,7 @@ impl Provider for AcpProvider {
                         break;
                     }
                     AcpUpdate::Error(e) => {
-                        Err(ProviderError::RequestFailed(e))?;
+                        Err(provider_error_from_acp(e))?;
                     }
                 }
             }
@@ -1108,6 +1116,11 @@ fn log_undelivered<E: std::fmt::Debug>(result: Result<(), E>, method: &str) {
     }
 }
 
+fn acp_method_error(method: &str, error: agent_client_protocol::Error) -> anyhow::Error {
+    let message = format!("ACP {method} failed: {error}");
+    anyhow::Error::new(error).context(message)
+}
+
 async fn handle_requests(
     config: AcpProviderConfig,
     goose_mode: Arc<Mutex<GooseMode>>,
@@ -1164,10 +1177,7 @@ async fn handle_requests(
                             .await?;
                         apply_session_mode(&config, &goose_mode, &cx, session).await
                     }
-                    Err(err) => Err(anyhow::anyhow!(
-                        "ACP {} failed: {err}",
-                        AGENT_METHOD_NAMES.session_new
-                    )),
+                    Err(error) => Err(acp_method_error(AGENT_METHOD_NAMES.session_new, error)),
                 };
                 log_undelivered(response_tx.send(result), AGENT_METHOD_NAMES.session_new);
             }
@@ -1273,7 +1283,7 @@ async fn handle_requests(
                     }
                     Err(e) => {
                         log_undelivered(
-                            response_tx.try_send(AcpUpdate::Error(e.to_string())),
+                            response_tx.try_send(AcpUpdate::Error(e)),
                             AGENT_METHOD_NAMES.session_prompt,
                         );
                     }
@@ -1800,7 +1810,7 @@ mod tests {
     use super::*;
     use crate::agents::extension::Envs;
     use agent_client_protocol::schema::v1::{
-        SessionConfigSelectOption, SessionMode, SessionModeId,
+        ErrorCode, SessionConfigSelectOption, SessionMode, SessionModeId,
     };
 
     use test_case::test_case;
@@ -1812,6 +1822,68 @@ mod tests {
         }
     }
 
+    fn acp_error_code(error: &anyhow::Error) -> Option<ErrorCode> {
+        error.chain().find_map(|source| {
+            source
+                .downcast_ref::<agent_client_protocol::Error>()
+                .map(|error| error.code)
+        })
+    }
+
+    #[test]
+    fn session_new_error_preserves_auth_required_code() {
+        let error = acp_method_error(
+            AGENT_METHOD_NAMES.session_new,
+            agent_client_protocol::Error::auth_required(),
+        );
+
+        assert_eq!(
+            error.to_string(),
+            "ACP session/new failed: Authentication required"
+        );
+        assert_eq!(acp_error_code(&error), Some(ErrorCode::AuthRequired));
+    }
+
+    #[test]
+    fn session_new_error_preserves_non_authentication_code() {
+        let error = acp_method_error(
+            AGENT_METHOD_NAMES.session_new,
+            agent_client_protocol::Error::internal_error(),
+        );
+
+        assert_eq!(acp_error_code(&error), Some(ErrorCode::InternalError));
+    }
+
+    #[tokio::test]
+    async fn prompt_error_update_preserves_auth_required_code() {
+        let (tx, mut rx) = mpsc::channel(1);
+        tx.send(AcpUpdate::Error(
+            agent_client_protocol::Error::auth_required().data("sign in"),
+        ))
+        .await
+        .unwrap();
+
+        let AcpUpdate::Error(error) = rx.recv().await.unwrap() else {
+            panic!("expected ACP error update");
+        };
+        assert_eq!(error.code, ErrorCode::AuthRequired);
+        assert_eq!(error.data, Some(serde_json::json!("sign in")));
+    }
+
+    #[test]
+    fn prompt_auth_error_maps_to_provider_authentication() {
+        let error = provider_error_from_acp(agent_client_protocol::Error::auth_required());
+
+        assert!(matches!(error, ProviderError::Authentication(_)));
+    }
+
+    #[test]
+    fn prompt_internal_error_remains_request_failed() {
+        let error = provider_error_from_acp(agent_client_protocol::Error::internal_error());
+
+        assert!(matches!(error, ProviderError::RequestFailed(_)));
+    }
+
     fn test_provider() -> (AcpProvider, ModelConfig) {
         test_provider_with_tx(None)
     }
diff --git a/crates/goose/src/acp/server.rs b/crates/goose/src/acp/server.rs
index 6bb3f2597..50a2ca887 100644
--- a/crates/goose/src/acp/server.rs
+++ b/crates/goose/src/acp/server.rs
@@ -157,6 +157,14 @@ impl<T, E: std::fmt::Display> ResultExt<T> for Result<T, E> {
     }
 }
 
+fn agent_creation_error(error: anyhow::Error, context: &str) -> agent_client_protocol::Error {
+    if crate::acp::is_auth_required(&error) {
+        agent_client_protocol::Error::auth_required()
+    } else {
+        agent_client_protocol::Error::internal_error().data(format!("{context}: {error}"))
+    }
+}
+
 pub(super) const DEFAULT_PROVIDER_ID: &str = "goose";
 pub(super) const DEFAULT_PROVIDER_LABEL: &str = "Goose (Default)";
 const PROVIDER_CONFIG_STATUS_CHECK_CONCURRENCY: usize = 16;
@@ -760,7 +768,7 @@ impl GooseAcpAgent {
                 },
             )
             .await
-            .internal_err_ctx("Failed to create agent")
+            .map_err(|error| agent_creation_error(error, "Failed to create agent"))
     }
 
     fn initial_session_extensions(
@@ -1337,6 +1345,11 @@ fn prompt_error_from_message_content(
     content_item: &MessageContent,
 ) -> Option<agent_client_protocol::Error> {
     match content_item {
+        MessageContent::Error(error)
+            if error.kind == crate::conversation::message::MessageErrorKind::Authentication =>
+        {
+            Some(agent_client_protocol::Error::auth_required())
+        }
         MessageContent::SystemNotification(notification)
             if notification.notification_type == SystemNotificationType::CreditsExhausted =>
         {
@@ -2358,6 +2371,30 @@ mod tests {
     use tempfile::NamedTempFile;
     use test_case::test_case;
 
+    #[test]
+    fn agent_creation_auth_error_maps_to_auth_required() {
+        let error = anyhow::Error::new(agent_client_protocol::Error::auth_required());
+
+        let error = agent_creation_error(error, "Failed to create agent");
+
+        assert_eq!(
+            error.code,
+            agent_client_protocol::schema::v1::ErrorCode::AuthRequired
+        );
+    }
+
+    #[test]
+    fn agent_creation_non_auth_error_remains_internal() {
+        let error = anyhow::Error::new(agent_client_protocol::Error::internal_error());
+
+        let error = agent_creation_error(error, "Failed to create agent");
+
+        assert_eq!(
+            error.code,
+            agent_client_protocol::schema::v1::ErrorCode::InternalError
+        );
+    }
+
     fn config_with_yaml(yaml: &str) -> (Config, NamedTempFile, NamedTempFile) {
         let config_file = NamedTempFile::new().unwrap();
         let secrets_file = NamedTempFile::new().unwrap();
@@ -2607,6 +2644,21 @@ print(\"hello, world\")
         );
     }
 
+    #[test]
+    fn test_authentication_message_maps_to_auth_required() {
+        let content = MessageContent::error(
+            crate::conversation::message::MessageErrorKind::Authentication,
+            "Authentication required",
+        );
+
+        let error = prompt_error_from_message_content(&content).expect("expected prompt error");
+
+        assert_eq!(
+            error.code,
+            agent_client_protocol::schema::v1::ErrorCode::AuthRequired
+        );
+    }
+
     #[test]
     fn test_non_credit_system_notification_does_not_map_to_prompt_error() {
         let content = MessageContent::SystemNotification(SystemNotificationContent {
diff --git a/crates/goose/src/agents/agent.rs b/crates/goose/src/agents/agent.rs
index af8a4154c..4a9576ada 100644
--- a/crates/goose/src/agents/agent.rs
+++ b/crates/goose/src/agents/agent.rs
@@ -86,6 +86,11 @@ const EMPTY_TURN_MESSAGE: &str =
     "The model returned an empty response. Please resend your message to continue.";
 const DEFAULT_FRONTEND_INSTRUCTIONS: &str = "The following tools are provided directly by the frontend and will be executed by the frontend when called.";
 
+fn provider_creation_error(error: anyhow::Error, context: impl fmt::Display) -> anyhow::Error {
+    let message = format!("{context}: {error}");
+    error.context(message)
+}
+
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 enum ToolCategory {
     Shell,
@@ -3045,6 +3050,21 @@ impl Agent {
                             exit_chat = true;
                             break;
                         }
+                        Err(ref provider_err @ ProviderError::Authentication(_)) => {
+                            provider_errored = true;
+                            #[cfg(feature = "telemetry")]
+                            crate::posthog::emit_error(provider_err.telemetry_type(), &provider_err.to_string());
+                            error!("Error: {}", provider_err);
+                            let message = persist_and_push_message_with_id(
+                                &session_manager,
+                                &session_config.id,
+                                &mut conversation,
+                                Message::from_provider_error(provider_err),
+                            )
+                            .await?;
+                            yield AgentEvent::Message(message);
+                            break;
+                        }
                         Err(ref provider_err @ ProviderError::NetworkError(_)) => {
                             provider_errored = true;
                             #[cfg(feature = "telemetry")]
@@ -3478,7 +3498,7 @@ impl Agent {
             session.working_dir.clone(),
         )
         .await
-        .map_err(|e| anyhow!("Could not create provider: {}", e))?;
+        .map_err(|error| provider_creation_error(error, "Could not create provider"))?;
 
         self.update_provider(provider, model_config, session_id)
             .await?;
@@ -3555,7 +3575,7 @@ impl Agent {
                     session.working_dir.clone(),
                 )
                 .await
-                .map_err(|e| anyhow!("Could not create provider: {}", e))?;
+                .map_err(|error| provider_creation_error(error, "Could not create provider"))?;
                 (p, model_config, false)
             } else {
                 let fallback_provider_name = config
@@ -3592,12 +3612,12 @@ impl Agent {
                     session.working_dir.clone(),
                 )
                 .await
-                .map_err(|e| {
-                    anyhow!(
-                        "Could not create provider '{}' or fallback '{}': {}",
-                        provider_name,
-                        fallback_provider_name,
-                        e
+                .map_err(|error| {
+                    provider_creation_error(
+                        error,
+                        format!(
+                            "Could not create provider '{provider_name}' or fallback '{fallback_provider_name}'"
+                        ),
                     )
                 })?;
 
@@ -3957,6 +3977,26 @@ mod tests {
     use std::sync::atomic::{AtomicUsize, Ordering};
     use tempfile::TempDir;
 
+    #[test]
+    fn provider_creation_context_preserves_acp_error_code() {
+        let source = anyhow::Error::new(agent_client_protocol::Error::auth_required())
+            .context("ACP session/new failed: Authentication required");
+
+        let error = provider_creation_error(source, "Could not create provider");
+
+        assert_eq!(
+            error.to_string(),
+            "Could not create provider: ACP session/new failed: Authentication required"
+        );
+        assert!(error.chain().any(|source| {
+            source
+                .downcast_ref::<agent_client_protocol::Error>()
+                .is_some_and(|error| {
+                    error.code == agent_client_protocol::schema::v1::ErrorCode::AuthRequired
+                })
+        }));
+    }
+
     #[test]
     fn provider_session_id_comes_from_latest_inference() {
         let messages = vec![
diff --git a/crates/goose/src/execution/manager.rs b/crates/goose/src/execution/manager.rs
index bac39df5e..96d929861 100644
--- a/crates/goose/src/execution/manager.rs
+++ b/crates/goose/src/execution/manager.rs
@@ -214,11 +214,14 @@ impl AgentManager {
                     "Restoring evicted session {} (provider: {:?})",
                     session_id, session.provider_name
                 );
-                if let Err(e) = agent.restore_provider_from_session(&session).await {
+                if let Err(error) = agent.restore_provider_from_session(&session).await {
+                    if crate::acp::is_auth_required(&error) {
+                        return Err(error);
+                    }
                     tracing::warn!(
                         "Failed to restore provider for session {}: {}",
                         session_id,
-                        e
+                        error
                     );
                 }
             }
diff --git a/crates/goose/src/gateway/handler.rs b/crates/goose/src/gateway/handler.rs
index 7854dee1b..0d88a600f 100644
--- a/crates/goose/src/gateway/handler.rs
+++ b/crates/goose/src/gateway/handler.rs
@@ -422,10 +422,25 @@ impl GatewayHandler {
                 .await?;
         }
 
-        let agent = self
+        let agent = match self
             .agent_manager
             .get_or_create_agent(session_id.to_string())
-            .await?;
+            .await
+        {
+            Ok(agent) => agent,
+            Err(error) if crate::acp::is_auth_required(&error) => {
+                self.gateway
+                    .send_message(
+                        &message.user,
+                        OutgoingMessage::Text {
+                            body: format!("⚠️ Failed to configure provider: {error}"),
+                        },
+                    )
+                    .await?;
+                return Ok(());
+            }
+            Err(error) => return Err(error),
+        };
 
         // Re-read the session after sync so restore picks up the new values.
         let session = self
diff --git a/ui/desktop/src/acp/__tests__/chatSessionController.test.ts b/ui/desktop/src/acp/__tests__/chatSessionController.test.ts
index 86f761274..6bbf5a529 100644
--- a/ui/desktop/src/acp/__tests__/chatSessionController.test.ts
+++ b/ui/desktop/src/acp/__tests__/chatSessionController.test.ts
@@ -169,6 +169,20 @@ describe('acpChatSessionController.loadSession', () => {
     );
   });
 
+  it('retries a failed cached session load', async () => {
+    vi.mocked(acpChatSessionStore.getSnapshot).mockReturnValue({
+      ...snapshotWithActivePrompt(null),
+      session: loadedSession(),
+      sessionLoadError: 'Sign in to your provider, then try again.',
+    });
+    vi.mocked(isAcpSessionLoadInFlight).mockReturnValue(false);
+
+    await acpChatSessionController.loadSession(SESSION_ID);
+
+    expect(acpChatSessionActions.startSessionLoad).toHaveBeenCalledWith(SESSION_ID);
+    expect(acpLoadSession).toHaveBeenCalledWith(SESSION_ID);
+  });
+
   it('restores a cached session from the server', async () => {
     vi.mocked(acpChatSessionStore.getSnapshot).mockReturnValue({
       ...snapshotWithActivePrompt(null),
@@ -252,6 +266,7 @@ describe('acpChatSessionController.submitMessage', () => {
     expect(acpChatSessionActions.startPromptAttempt).not.toHaveBeenCalled();
     expect(acpPromptSession).not.toHaveBeenCalled();
   });
+
 });
 
 describe('acpChatSessionController.updateMessage', () => {
diff --git a/ui/desktop/src/acp/__tests__/chatSessionStore.test.ts b/ui/desktop/src/acp/__tests__/chatSessionStore.test.ts
index 431649bd4..c3fb846c6 100644
--- a/ui/desktop/src/acp/__tests__/chatSessionStore.test.ts
+++ b/ui/desktop/src/acp/__tests__/chatSessionStore.test.ts
@@ -242,13 +242,9 @@ describe('acpChatSessionStore', () => {
     acpChatSessionActions.startPromptAttempt(currentSessionId, 'attempt-a');
     acpChatSessionActions.startPromptAttempt(currentSessionId, 'attempt-b');
 
-    expect(
-      acpChatSessionActions.finishPromptAttemptIfCurrent(
-        currentSessionId,
-        'attempt-a',
-        'late error'
-      )
-    ).toBe(false);
+    expect(acpChatSessionActions.finishPromptAttemptIfCurrent(currentSessionId, 'attempt-a')).toBe(
+      false
+    );
 
     expect(acpChatSessionStore.getSnapshot(currentSessionId)).toMatchObject({
       activePromptAttemptId: 'attempt-b',
diff --git a/ui/desktop/src/acp/__tests__/errors.test.ts b/ui/desktop/src/acp/__tests__/errors.test.ts
index 31c9b3b42..74dc4ca0d 100644
--- a/ui/desktop/src/acp/__tests__/errors.test.ts
+++ b/ui/desktop/src/acp/__tests__/errors.test.ts
@@ -1,5 +1,14 @@
 import { describe, expect, it } from 'vitest';
-import { parseAcpCreditsExhaustedError } from '../errors';
+import { RequestError } from '@agentclientprotocol/sdk';
+import { formatAcpError, parseAcpCreditsExhaustedError } from '../errors';
+
+describe('formatAcpError', () => {
+  it('explains how to recover from an authentication error', () => {
+    expect(formatAcpError(RequestError.authRequired())).toBe(
+      'Sign in to your provider, then try again.'
+    );
+  });
+});
 
 describe('parseAcpCreditsExhaustedError', () => {
   it('parses structured ACP credits exhausted errors', () => {
diff --git a/ui/desktop/src/acp/chatSessionController.ts b/ui/desktop/src/acp/chatSessionController.ts
index b80f1aa8c..394654577 100644
--- a/ui/desktop/src/acp/chatSessionController.ts
+++ b/ui/desktop/src/acp/chatSessionController.ts
@@ -3,7 +3,6 @@ import type { GooseExtension } from '@aaif/goose-sdk';
 import { AppEvents } from '../constants/events';
 import { ChatState } from '../types/chatState';
 import type { Session } from '../types/session';
-import { errorMessage } from '../utils/conversionUtils';
 import { showExtensionLoadResults } from '../utils/extensionErrorUtils';
 import {
   createUserMessage,
@@ -17,7 +16,11 @@ import {
   type AcpChatSessionSnapshot,
 } from './chatSessionStore';
 import { cancelAcpElicitationRequestsForSession } from './elicitationRequests';
-import { parseAcpCreditsExhaustedError, type AcpCreditsExhaustedError } from './errors';
+import {
+  formatAcpError,
+  parseAcpCreditsExhaustedError,
+  type AcpCreditsExhaustedError,
+} from './errors';
 import { cancelAcpPermissionRequestsForSession } from './permissionRequests';
 import { acpCancelPrompt, acpPromptSession } from './prompt';
 import {
@@ -128,7 +131,7 @@ async function createSession(
 
 async function loadSession(sessionId: string, options: AcpLoadSessionOptions = {}): Promise<void> {
   const cached = acpChatSessionStore.getSnapshot(sessionId);
-  if (cached?.session) {
+  if (cached?.session && !cached.sessionLoadError) {
     window.dispatchEvent(
       new CustomEvent(AppEvents.SESSION_EXTENSIONS_LOADED, { detail: { sessionId } })
     );
@@ -162,7 +165,7 @@ async function loadSessionFromServer(
     options.onSessionLoaded?.();
   } catch (error) {
     console.error('Failed to load ACP session:', error);
-    acpChatSessionActions.failSessionLoad(sessionId, errorMessage(error));
+    acpChatSessionActions.failSessionLoad(sessionId, formatAcpError(error));
   }
 }
 
@@ -211,10 +214,8 @@ async function submitMessage(
       return;
     }
 
-    const submitError = 'Submit error: ' + errorMessage(error);
-    if (
-      acpChatSessionActions.finishPromptAttemptIfCurrent(sessionId, promptAttemptId, submitError)
-    ) {
+    const submitError = formatAcpError(error);
+    if (acpChatSessionActions.finishPromptAttemptIfCurrent(sessionId, promptAttemptId)) {
       void options.onFinish(submitError);
     }
   }
diff --git a/ui/desktop/src/acp/chatSessionStore.ts b/ui/desktop/src/acp/chatSessionStore.ts
index 19fa8dcfb..021b86691 100644
--- a/ui/desktop/src/acp/chatSessionStore.ts
+++ b/ui/desktop/src/acp/chatSessionStore.ts
@@ -104,7 +104,7 @@ export interface AcpChatSessionActions {
     promptAttemptId: string
   ): AcpChatSessionSnapshot | undefined;
   waitForPromptCancellation(sessionId: string, promptAttemptId: string): Promise<void>;
-  finishPromptAttemptIfCurrent(sessionId: string, promptAttemptId: string, error?: string): boolean;
+  finishPromptAttemptIfCurrent(sessionId: string, promptAttemptId: string): boolean;
   clearActivePromptAttempt(sessionId: string): AcpChatSessionSnapshot | undefined;
   isCurrentPromptAttempt(sessionId: string, promptAttemptId: string): boolean;
 }
@@ -403,8 +403,7 @@ function createAcpChatSessionStoreInternal(): AcpChatSessionStoreInternal {
 
   const finishPromptAttemptIfCurrent: AcpChatSessionActions['finishPromptAttemptIfCurrent'] = (
     sessionId,
-    promptAttemptId,
-    error
+    promptAttemptId
   ) => {
     const entry = sessionsById.get(sessionId);
     if (!entry || entry.activePromptAttemptId !== promptAttemptId) {
@@ -419,7 +418,6 @@ function createAcpChatSessionStoreInternal(): AcpChatSessionStoreInternal {
     discardPendingLocalSteerMessages(entry);
     entry.progressMessage = undefined;
     entry.chatState = ChatState.Idle;
-    entry.sessionLoadError = error;
     notify(sessionId, entry);
     return true;
   };
diff --git a/ui/desktop/src/acp/errors.ts b/ui/desktop/src/acp/errors.ts
index 16dd95f3a..67ab0ec77 100644
--- a/ui/desktop/src/acp/errors.ts
+++ b/ui/desktop/src/acp/errors.ts
@@ -1,9 +1,13 @@
+import { RequestError } from '@agentclientprotocol/sdk';
+import { errorMessage } from '../utils/conversionUtils';
+
 export interface AcpCreditsExhaustedError {
   message: string;
   url?: string;
 }
 
 const CREDITS_EXHAUSTED_REASON = 'credits_exhausted';
+const AUTH_REQUIRED_CODE = -32000;
 
 // Kept in sync with RECIPE_PARAMS_CANCELLED_REASON in crates/goose/src/acp/server/recipe.rs.
 const RECIPE_PARAMS_CANCELLED_REASON = 'recipe_params_cancelled';
@@ -42,6 +46,13 @@ export function parseAcpCreditsExhaustedError(error: unknown): AcpCreditsExhaust
   };
 }
 
+export function formatAcpError(error: unknown): string {
+  if (error instanceof RequestError && error.code === AUTH_REQUIRED_CODE) {
+    return 'Sign in to your provider, then try again.';
+  }
+  return errorMessage(error);
+}
+
 interface AcpJsonRpcError {
   message: string;
   data: Record<string, unknown>;
diff --git a/ui/desktop/src/components/BaseChat.tsx b/ui/desktop/src/components/BaseChat.tsx
index 7bebcac2e..4073d4dfc 100644
--- a/ui/desktop/src/components/BaseChat.tsx
+++ b/ui/desktop/src/components/BaseChat.tsx
@@ -8,6 +8,7 @@ import ProgressiveMessageList from './ProgressiveMessageList';
 import { MainPanelLayout } from './Layout/MainPanelLayout';
 import ChatInput from './ChatInput';
 import { ChatInputCard } from './ChatInputCard';
+import { Button } from './ui/button';
 import { ScrollArea, ScrollAreaHandle } from './ui/scroll-area';
 import { useFileDrop } from '../hooks/useFileDrop';
 import { ChatState } from '../types/chatState';
@@ -45,6 +46,10 @@ const i18n = defineMessages({
     id: 'baseChat.goHome',
     defaultMessage: 'Go home',
   },
+  retry: {
+    id: 'baseChat.retry',
+    defaultMessage: 'Retry',
+  },
   reconnecting: {
     id: 'baseChat.reconnecting',
     defaultMessage: 'Connection lost. Reconnecting…',
@@ -106,6 +111,7 @@ export default function BaseChat({
     onSteerQueuedMessage,
     submitElicitationResponse,
     stopStreaming,
+    retrySessionLoad,
     sessionLoadError,
     tokenState,
     notifications: toolCallNotifications,
@@ -384,14 +390,14 @@ export default function BaseChat({
                   </h3>
                   <p className="text-sm">{sessionLoadError}</p>
                 </div>
-                <button
-                  onClick={() => {
-                    setView('chat');
-                  }}
-                  className="px-4 py-2 text-center cursor-pointer text-text-primary border border-border-primary hover:bg-background-secondary rounded-lg transition-all duration-150"
-                >
-                  {intl.formatMessage(i18n.goHome)}
-                </button>
+                <div className="flex gap-2">
+                  <Button variant="outline" onClick={() => void retrySessionLoad()}>
+                    {intl.formatMessage(i18n.retry)}
+                  </Button>
+                  <Button variant="outline" onClick={() => setView('chat')}>
+                    {intl.formatMessage(i18n.goHome)}
+                  </Button>
+                </div>
               </div>
             </div>
           </div>
diff --git a/ui/desktop/src/components/ChatInput.tsx b/ui/desktop/src/components/ChatInput.tsx
index 1e4979600..b3df9387d 100644
--- a/ui/desktop/src/components/ChatInput.tsx
+++ b/ui/desktop/src/components/ChatInput.tsx
@@ -1118,7 +1118,9 @@ export default function ChatInput({
           setLastInterruption(null);
         }
 
-        clearInputState();
+        if (sessionId !== null) {
+          clearInputState();
+        }
         setHistoryIndex(-1);
         setSavedInput('');
         setIsInGlobalHistory(false);
@@ -1133,6 +1135,7 @@ export default function ChatInput({
       handleSubmit,
       lastInterruption,
       clearInputState,
+      sessionId,
     ]
   );
 
diff --git a/ui/desktop/src/components/Hub.tsx b/ui/desktop/src/components/Hub.tsx
index 7deca289f..873af656c 100644
--- a/ui/desktop/src/components/Hub.tsx
+++ b/ui/desktop/src/components/Hub.tsx
@@ -25,6 +25,8 @@ import {
   selectNextChatExtensions,
   type NextChatExtensionDraft,
 } from '../utils/nextChatExtensions';
+import { formatAcpError } from '../acp/errors';
+import { toastError } from '../toasts';
 
 const i18n = defineMessages({
   goodMorning: { id: 'hub.goodMorning', defaultMessage: 'Good morning' },
@@ -116,6 +118,7 @@ export default function Hub({
       });
     } catch (error) {
       console.error('Failed to create session:', error);
+      toastError({ title: "Couldn't start chat", msg: formatAcpError(error) });
       setIsCreatingSession(false);
     }
   };
diff --git a/ui/desktop/src/hooks/useChatSession.ts b/ui/desktop/src/hooks/useChatSession.ts
index 6cb7783b5..3659dbd70 100644
--- a/ui/desktop/src/hooks/useChatSession.ts
+++ b/ui/desktop/src/hooks/useChatSession.ts
@@ -1,6 +1,7 @@
 import { useCallback, useEffect, useMemo, useRef } from 'react';
 import { defineMessages, useIntl } from '../i18n';
 import { AppEvents } from '../constants/events';
+import { toastError } from '../toasts';
 import { ChatState } from '../types/chatState';
 
 import type { TokenState } from '../types/chat';
@@ -108,7 +109,9 @@ export function useChatSession({
 
   const onFinish = useCallback(
     async (error?: string): Promise<void> => {
-      if (!error) {
+      if (error) {
+        toastError({ title: "Couldn't send message", msg: error });
+      } else {
         try {
           const [notificationsEnabled, anyWindowFocused] = await Promise.all([
             window.electron.getSetting('enableNotifications'),
@@ -143,12 +146,15 @@ export function useChatSession({
     [getCurrentSnapshot, onFinish, sessionId]
   );
 
+  const retrySessionLoad = useCallback(
+    () => acpChatSessionController.loadSession(sessionId, { onSessionLoaded }),
+    [sessionId, onSessionLoaded]
+  );
+
   // Load session on mount or sessionId change
   useEffect(() => {
-    if (!sessionId) return;
-
-    void acpChatSessionController.loadSession(sessionId, { onSessionLoaded });
-  }, [sessionId, onSessionLoaded]);
+    void retrySessionLoad();
+  }, [retrySessionLoad]);
 
   const handleSubmit = useCallback(
     async (input: UserInput) => {
@@ -302,7 +308,6 @@ export function useChatSession({
       } catch (error) {
         const errorMsg = errorMessage(error);
         console.error('Failed to edit message:', error);
-        const { toastError } = await import('../toasts');
         toastError({
           title: 'Failed to edit message',
           msg: errorMsg,
@@ -344,6 +349,7 @@ export function useChatSession({
     onSteerQueuedMessage,
     submitElicitationResponse,
     stopStreaming,
+    retrySessionLoad,
     tokenState,
     notifications: notificationsMap,
     pauseQueueOnStop: false,
diff --git a/ui/desktop/src/hooks/useChatSessionTypes.ts b/ui/desktop/src/hooks/useChatSessionTypes.ts
index c042986ed..ccd5fbad9 100644
--- a/ui/desktop/src/hooks/useChatSessionTypes.ts
+++ b/ui/desktop/src/hooks/useChatSessionTypes.ts
@@ -22,6 +22,7 @@ export interface UseChatSessionResult {
     userData: Record<string, unknown>
   ) => Promise<boolean>;
   stopStreaming: () => void;
+  retrySessionLoad: () => Promise<void>;
   sessionLoadError?: string;
   tokenState: TokenState;
   notifications: Map<string, NotificationEvent[]>;
diff --git a/ui/desktop/src/i18n/messages/de.json b/ui/desktop/src/i18n/messages/de.json
index 1394f52d0..594a301b5 100644
--- a/ui/desktop/src/i18n/messages/de.json
+++ b/ui/desktop/src/i18n/messages/de.json
@@ -134,6 +134,9 @@
   "baseChat.reconnecting": {
     "defaultMessage": "Verbindung unterbrochen. Verbindung wird wiederhergestellt…"
   },
+  "baseChat.retry": {
+    "defaultMessage": "Wiederholen"
+  },
   "bottomMenuExtensionSelection.extensionUpdated": {
     "defaultMessage": "Erweiterung aktualisiert"
   },
diff --git a/ui/desktop/src/i18n/messages/en.json b/ui/desktop/src/i18n/messages/en.json
index 97dccaec4..6159d33dc 100644
--- a/ui/desktop/src/i18n/messages/en.json
+++ b/ui/desktop/src/i18n/messages/en.json
@@ -134,6 +134,9 @@
   "baseChat.reconnecting": {
     "defaultMessage": "Connection lost. Reconnecting…"
   },
+  "baseChat.retry": {
+    "defaultMessage": "Retry"
+  },
   "bottomMenuExtensionSelection.extensionUpdated": {
     "defaultMessage": "Extension Updated"
   },
diff --git a/ui/desktop/src/i18n/messages/es.json b/ui/desktop/src/i18n/messages/es.json
index a36515f56..357c2e5b2 100644
--- a/ui/desktop/src/i18n/messages/es.json
+++ b/ui/desktop/src/i18n/messages/es.json
@@ -134,6 +134,9 @@
   "baseChat.reconnecting": {
     "defaultMessage": "Conexión perdida. Reconectando…"
   },
+  "baseChat.retry": {
+    "defaultMessage": "Reintentar"
+  },
   "bottomMenuExtensionSelection.extensionUpdated": {
     "defaultMessage": "Extensión actualizada"
   },
diff --git a/ui/desktop/src/i18n/messages/fr.json b/ui/desktop/src/i18n/messages/fr.json
index f9b34b292..62f4847ba 100644
--- a/ui/desktop/src/i18n/messages/fr.json
+++ b/ui/desktop/src/i18n/messages/fr.json
@@ -134,6 +134,9 @@
   "baseChat.reconnecting": {
     "defaultMessage": "Connexion perdue. Reconnexion…"
   },
+  "baseChat.retry": {
+    "defaultMessage": "Réessayer"
+  },
   "bottomMenuExtensionSelection.extensionUpdated": {
     "defaultMessage": "Extension mise à jour"
   },
diff --git a/ui/desktop/src/i18n/messages/hi.json b/ui/desktop/src/i18n/messages/hi.json
index 53f8843f5..16da17425 100644
--- a/ui/desktop/src/i18n/messages/hi.json
+++ b/ui/desktop/src/i18n/messages/hi.json
@@ -134,6 +134,9 @@
   "baseChat.reconnecting": {
     "defaultMessage": "कनेक्शन टूट गया। फिर से कनेक्ट किया जा रहा है…"
   },
+  "baseChat.retry": {
+    "defaultMessage": "पुनः प्रयास करें"
+  },
   "bottomMenuExtensionSelection.extensionUpdated": {
     "defaultMessage": "एक्सटेंशन अपडेट किया गया"
   },
diff --git a/ui/desktop/src/i18n/messages/id.json b/ui/desktop/src/i18n/messages/id.json
index 171c459ba..801b24d8b 100644
--- a/ui/desktop/src/i18n/messages/id.json
+++ b/ui/desktop/src/i18n/messages/id.json
@@ -134,6 +134,9 @@
   "baseChat.reconnecting": {
     "defaultMessage": "Koneksi terputus. Menghubungkan kembali…"
   },
+  "baseChat.retry": {
+    "defaultMessage": "Coba lagi"
+  },
   "bottomMenuExtensionSelection.extensionUpdated": {
     "defaultMessage": "Ekstensi Diperbarui"
   },
diff --git a/ui/desktop/src/i18n/messages/it.json b/ui/desktop/src/i18n/messages/it.json
index dc9ef517f..438d25d56 100644
--- a/ui/desktop/src/i18n/messages/it.json
+++ b/ui/desktop/src/i18n/messages/it.json
@@ -134,6 +134,9 @@
   "baseChat.reconnecting": {
     "defaultMessage": "Connessione persa. Riconnessione…"
   },
+  "baseChat.retry": {
+    "defaultMessage": "Riprova"
+  },
   "bottomMenuExtensionSelection.extensionUpdated": {
     "defaultMessage": "Estensione aggiornata"
   },
diff --git a/ui/desktop/src/i18n/messages/ja.json b/ui/desktop/src/i18n/messages/ja.json
index c6ace5135..9ea61dc08 100644
--- a/ui/desktop/src/i18n/messages/ja.json
+++ b/ui/desktop/src/i18n/messages/ja.json
@@ -134,6 +134,9 @@
   "baseChat.reconnecting": {
     "defaultMessage": "接続が失われました。再接続しています…"
   },
+  "baseChat.retry": {
+    "defaultMessage": "再試行"
+  },
   "bottomMenuExtensionSelection.extensionUpdated": {
     "defaultMessage": "拡張機能を更新しました"
   },
diff --git a/ui/desktop/src/i18n/messages/ko.json b/ui/desktop/src/i18n/messages/ko.json
index 8ae95337d..a97e65788 100644
--- a/ui/desktop/src/i18n/messages/ko.json
+++ b/ui/desktop/src/i18n/messages/ko.json
@@ -134,6 +134,9 @@
   "baseChat.reconnecting": {
     "defaultMessage": "연결이 끊어졌습니다. 다시 연결하는 중…"
   },
+  "baseChat.retry": {
+    "defaultMessage": "다시 시도"
+  },
   "bottomMenuExtensionSelection.extensionUpdated": {
     "defaultMessage": "익스텐션이 업데이트되었습니다."
   },
diff --git a/ui/desktop/src/i18n/messages/ms.json b/ui/desktop/src/i18n/messages/ms.json
index 5f5034466..ce7f3bd9c 100644
--- a/ui/desktop/src/i18n/messages/ms.json
+++ b/ui/desktop/src/i18n/messages/ms.json
@@ -134,6 +134,9 @@
   "baseChat.reconnecting": {
     "defaultMessage": "Sambungan terputus. Menyambung semula…"
   },
+  "baseChat.retry": {
+    "defaultMessage": "Cuba semula"
+  },
   "bottomMenuExtensionSelection.extensionUpdated": {
     "defaultMessage": "Sambungan Dikemas Kini"
   },
diff --git a/ui/desktop/src/i18n/messages/pt.json b/ui/desktop/src/i18n/messages/pt.json
index 99080d278..bb0a2b735 100644
--- a/ui/desktop/src/i18n/messages/pt.json
+++ b/ui/desktop/src/i18n/messages/pt.json
@@ -134,6 +134,9 @@
   "baseChat.reconnecting": {
     "defaultMessage": "Conexão perdida. Reconectando…"
   },
+  "baseChat.retry": {
+    "defaultMessage": "Tentar novamente"
+  },
   "bottomMenuExtensionSelection.extensionUpdated": {
     "defaultMessage": "Extensão atualizada"
   },
diff --git a/ui/desktop/src/i18n/messages/ru.json b/ui/desktop/src/i18n/messages/ru.json
index 7314709eb..50c2a4e75 100644
--- a/ui/desktop/src/i18n/messages/ru.json
+++ b/ui/desktop/src/i18n/messages/ru.json
@@ -134,6 +134,9 @@
   "baseChat.reconnecting": {
     "defaultMessage": "Соединение потеряно. Повторное подключение…"
   },
+  "baseChat.retry": {
+    "defaultMessage": "Повторить"
+  },
   "bottomMenuExtensionSelection.extensionUpdated": {
     "defaultMessage": "Расширение обновлено"
   },
diff --git a/ui/desktop/src/i18n/messages/tr.json b/ui/desktop/src/i18n/messages/tr.json
index 2a8ea5731..fbe9938f2 100644
--- a/ui/desktop/src/i18n/messages/tr.json
+++ b/ui/desktop/src/i18n/messages/tr.json
@@ -134,6 +134,9 @@
   "baseChat.reconnecting": {
     "defaultMessage": "Bağlantı kesildi. Yeniden bağlanılıyor…"
   },
+  "baseChat.retry": {
+    "defaultMessage": "Yeniden dene"
+  },
   "bottomMenuExtensionSelection.extensionUpdated": {
     "defaultMessage": "Uzantı Güncellendi"
   },
diff --git a/ui/desktop/src/i18n/messages/vi.json b/ui/desktop/src/i18n/messages/vi.json
index ccdf799d2..bb4da665c 100644
--- a/ui/desktop/src/i18n/messages/vi.json
+++ b/ui/desktop/src/i18n/messages/vi.json
@@ -134,6 +134,9 @@
   "baseChat.reconnecting": {
     "defaultMessage": "Mất kết nối. Đang kết nối lại…"
   },
+  "baseChat.retry": {
+    "defaultMessage": "Thử lại"
+  },
   "bottomMenuExtensionSelection.extensionUpdated": {
     "defaultMessage": "Đã cập nhật tiện ích mở rộng"
   },
diff --git a/ui/desktop/src/i18n/messages/zh-CN.json b/ui/desktop/src/i18n/messages/zh-CN.json
index a21fd2a47..54ad5d5dc 100644
--- a/ui/desktop/src/i18n/messages/zh-CN.json
+++ b/ui/desktop/src/i18n/messages/zh-CN.json
@@ -134,6 +134,9 @@
   "baseChat.reconnecting": {
     "defaultMessage": "连接已断开。正在重新连接…"
   },
+  "baseChat.retry": {
+    "defaultMessage": "重试"
+  },
   "bottomMenuExtensionSelection.extensionUpdated": {
     "defaultMessage": "扩展已更新"
   },
diff --git a/ui/desktop/src/i18n/messages/zh-TW.json b/ui/desktop/src/i18n/messages/zh-TW.json
index edd14fc6e..c9492db50 100644
--- a/ui/desktop/src/i18n/messages/zh-TW.json
+++ b/ui/desktop/src/i18n/messages/zh-TW.json
@@ -134,6 +134,9 @@
   "baseChat.reconnecting": {
     "defaultMessage": "連線已中斷。正在重新連線…"
   },
+  "baseChat.retry": {
+    "defaultMessage": "重試"
+  },
   "bottomMenuExtensionSelection.extensionUpdated": {
     "defaultMessage": "擴充功能已更新"
   },