🤖 refactor: decompose src/node/ god services — Phase 0+1+2a+3a

src/browser/components/ChatInput/useCreationWorkspace.ts

@@ -45,6 +45,7 @@ import { KNOWN_MODELS } from "@/common/constants/knownModels";
 import { getModelCapabilities } from "@/common/utils/ai/modelCapabilities";
 import { normalizeModelInput } from "@/browser/utils/models/normalizeModelInput";
 import { resolveDevcontainerSelection } from "@/browser/utils/devcontainerSelection";
+import { getErrorMessage } from "@/common/utils/errors";
 
 export type CreationSendResult = { success: true } | { success: false; error?: SendMessageError };
 
@@ -545,7 +546,7 @@ export function useCreationWorkspace({
 
         return { success: true };
       } catch (err) {
-        const errorMessage = err instanceof Error ? err.message : String(err);
+        const errorMessage = getErrorMessage(err);
         setToast({
           id: Date.now().toString(),
           type: "error",

src/browser/components/hooks/useGitBranchDetails.ts

@@ -7,6 +7,7 @@ import {
   type GitBranchHeader,
 } from "@/common/utils/git/parseGitLog";
 import { useAPI } from "@/browser/contexts/API";
+import { getErrorMessage } from "@/common/utils/errors";
 
 const GitBranchDataSchema = z.object({
   showBranch: z.string(),
@@ -274,9 +275,7 @@ printf '__MUX_BRANCH_DATA__BEGIN_DIRTY_FILES__\\n%s\\n__MUX_BRANCH_DATA__END_DIR
         timestamp: Date.now(),
       };
     } catch (error) {
-      setErrorMessage(
-        `Failed to fetch branch info: ${error instanceof Error ? error.message : String(error)}`
-      );
+      setErrorMessage(`Failed to fetch branch info: ${getErrorMessage(error)}`);
       setCommits(null);
     } finally {
       setIsLoading(false);

src/browser/hooks/useMuxGatewayAccountStatus.ts

@@ -5,6 +5,7 @@ import { CUSTOM_EVENTS, createCustomEvent } from "@/common/constants/events";
 import { GATEWAY_CONFIGURED_KEY } from "@/common/constants/storage";
 import { MUX_GATEWAY_SESSION_EXPIRED_MESSAGE } from "@/common/constants/muxGatewayOAuth";
 import { formatCostWithDollar } from "@/common/utils/tokens/usageAggregator";
+import { getErrorMessage } from "@/common/utils/errors";
 
 export interface MuxGatewayAccountStatus {
   remaining_microdollars: number;
@@ -51,7 +52,7 @@ export function useMuxGatewayAccountStatus() {
 
       setError(result.error);
     } catch (err) {
-      const message = err instanceof Error ? err.message : String(err);
+      const message = getErrorMessage(err);
       setError(message);
     } finally {
       setIsLoading(false);

src/browser/hooks/useVoiceInput.ts

@@ -11,6 +11,7 @@ import { matchesKeybind, KEYBINDS } from "@/browser/utils/ui/keybinds";
 import { stopKeyboardPropagation } from "@/browser/utils/events";
 import type { APIClient } from "@/browser/contexts/API";
 import { trackVoiceTranscription } from "@/common/telemetry";
+import { getErrorMessage } from "@/common/utils/errors";
 
 export type VoiceInputState = "idle" | "requesting" | "recording" | "transcribing";
 
@@ -187,7 +188,7 @@ export function useVoiceInput(options: UseVoiceInputOptions): UseVoiceInputResul
         setTimeout(() => callbacksRef.current.onSend?.(), 0);
       }
     } catch (err) {
-      const msg = err instanceof Error ? err.message : String(err);
+      const msg = getErrorMessage(err);
       callbacksRef.current.onError?.(`Transcription failed: ${msg}`);
       trackVoiceTranscription(audioDurationSecs, false);
     } finally {
@@ -265,7 +266,7 @@ export function useVoiceInput(options: UseVoiceInputOptions): UseVoiceInputResul
       recordingStartTimeRef.current = Date.now();
       setState("recording");
     } catch (err) {
-      const msg = err instanceof Error ? err.message : String(err);
+      const msg = getErrorMessage(err);
       const isPermissionDenied = msg.includes("Permission denied") || msg.includes("NotAllowed");
 
       callbacksRef.current.onError?.(

src/browser/hooks/useWorkspaceName.ts

@@ -6,6 +6,7 @@ import { getWorkspaceNameStateKey } from "@/common/constants/storage";
 import { useGateway, formatAsGatewayModel } from "./useGatewayModels";
 import { getKnownModel } from "@/common/constants/knownModels";
 import { validateWorkspaceName } from "@/common/utils/validation/workspaceValidation";
+import { getErrorMessage } from "@/common/utils/errors";
 
 /** Small/fast models preferred for name generation */
 const PREFERRED_MODELS = [getKnownModel("HAIKU").id, getKnownModel("GPT_MINI").id];
@@ -272,7 +273,7 @@ export function useWorkspaceName(options: UseWorkspaceNameOptions): UseWorkspace
         if (requestId !== requestIdRef.current) {
           return null;
         }
-        const errorMsg = err instanceof Error ? err.message : String(err);
+        const errorMsg = getErrorMessage(err);
         setError(errorMsg);
         safeResolve(null);
         return null;

src/browser/terminal/TerminalSessionRouter.ts

@@ -22,6 +22,7 @@
 
 import type { RouterClient } from "@orpc/server";
 import type { AppRouter } from "@/node/orpc/router";
+import { getErrorMessage } from "@/common/utils/errors";
 
 type APIClient = RouterClient<AppRouter>;
 
@@ -349,7 +350,7 @@ export class TerminalSessionRouter {
       } catch (err) {
         if (!signal.aborted) {
           // Ignore "session not found" errors for exit stream
-          const errMsg = err instanceof Error ? err.message : String(err);
+          const errMsg = getErrorMessage(err);
           if (!errMsg.includes("isOpen") && !errMsg.includes("undefined")) {
             console.error(`[TerminalRouter] Exit stream error for ${sessionId}:`, err);
           }

src/cli/run.ts

@@ -71,6 +71,7 @@ import { runFullInit } from "@/node/runtime/runtimeFactory";
 import { execSync } from "child_process";
 import { getParseOptions } from "./argv";
 import { EXPERIMENT_IDS } from "@/common/constants/experiments";
+import { getErrorMessage } from "@/common/utils/errors";
 
 // Display labels for CLI help (OFF, LOW, MED, HIGH, MAX)
 const THINKING_LABELS_LIST = Object.values(THINKING_DISPLAY_LABELS).join(", ");
@@ -530,7 +531,7 @@ async function main(): Promise<number> {
         initLogger,
       });
     } catch (error) {
-      const errorMessage = error instanceof Error ? error.message : String(error);
+      const errorMessage = getErrorMessage(error);
       initLogger.logStderr(`Initialization failed: ${errorMessage}`);
       initLogger.logComplete(-1);
       initResult = { success: false, error: errorMessage };
@@ -1111,6 +1112,6 @@ main()
   })
   .catch((error) => {
     clearInterval(keepAliveInterval);
-    console.error(`Error: ${error instanceof Error ? error.message : String(error)}`);
+    console.error(`Error: ${getErrorMessage(error)}`);
     process.exit(1);
   });

src/desktop/main.ts

@@ -1,5 +1,6 @@
 // Enable source map support for better error stack traces in production
 import "source-map-support/register";
+import { getErrorMessage } from "@/common/utils/errors";
 
 // Fix PATH on macOS when launched from Finder (not terminal).
 // GUI apps inherit minimal PATH from launchd, missing Homebrew tools like git-lfs.
@@ -109,7 +110,7 @@ if (process.env.MUX_DEBUG_START_TIME === "1") {
 process.on("uncaughtException", (error: unknown) => {
   console.error("Uncaught Exception:", error);
 
-  const message = error instanceof Error ? error.message : String(error);
+  const message = getErrorMessage(error);
   const stack = error instanceof Error ? error.stack : undefined;
 
   console.error("Stack:", stack);
@@ -128,7 +129,7 @@ process.on("unhandledRejection", (reason, promise) => {
   console.error("Reason:", reason);
 
   if (app.isPackaged) {
-    const message = reason instanceof Error ? reason.message : String(reason);
+    const message = getErrorMessage(reason);
     const stack = reason instanceof Error ? reason.stack : undefined;
     dialog.showErrorBox(
       "Unhandled Promise Rejection",

src/node/git.ts

@@ -5,6 +5,7 @@ import type { RuntimeConfig } from "@/common/types/runtime";
 import { execAsync } from "@/node/utils/disposableExec";
 import { createRuntime } from "./runtime/runtimeFactory";
 import { log } from "./services/log";
+import { getErrorMessage } from "@/common/utils/errors";
 
 /**
  * Remove stale .git/index.lock file if it exists and is old.
@@ -187,7 +188,7 @@ export async function createWorktree(
 
     return { success: true, path: workspacePath };
   } catch (error) {
-    const message = error instanceof Error ? error.message : String(error);
+    const message = getErrorMessage(error);
     return { success: false, error: message };
   }
 }
@@ -233,7 +234,7 @@ export async function removeWorktree(
     await proc.result;
     return { success: true };
   } catch (error) {
-    const message = error instanceof Error ? error.message : String(error);
+    const message = getErrorMessage(error);
     return { success: false, error: message };
   }
 }
@@ -247,7 +248,7 @@ export async function pruneWorktrees(projectPath: string): Promise<WorktreeResul
     await proc.result;
     return { success: true };
   } catch (error) {
-    const message = error instanceof Error ? error.message : String(error);
+    const message = getErrorMessage(error);
     return { success: false, error: message };
   }
 }

src/node/orpc/router.ts

@@ -62,6 +62,7 @@ import {
   readSubagentTranscriptArtifactsFile,
   type SubagentTranscriptArtifactIndexEntry,
 } from "@/node/services/subagentTranscriptArtifacts";
+import { getErrorMessage } from "@/common/utils/errors";
 
 /**
  * Resolves runtime and discovery path for agent operations.
@@ -154,7 +155,7 @@ async function readChatJsonlAllowMissing(params: {
       } catch (parseError) {
         log.warn(
           `Skipping malformed JSON at line ${i + 1} in ${params.logLabel}:`,
-          parseError instanceof Error ? parseError.message : String(parseError),
+          getErrorMessage(parseError),
           "\nLine content:",
           lines[i].substring(0, 100) + (lines[i].length > 100 ? "..." : "")
         );
@@ -184,7 +185,7 @@ async function readPartialJsonBestEffort(partialPath: string): Promise<MuxMessag
     // Never fail transcript viewing because partial.json is corrupted.
     log.warn("Failed to read partial.json for transcript", {
       partialPath,
-      error: error instanceof Error ? error.message : String(error),
+      error: getErrorMessage(error),
     });
     return null;
   }
@@ -1059,7 +1060,7 @@ export const router = (authToken?: string) => {
               },
             });
           } catch (error) {
-            const message = error instanceof Error ? error.message : String(error);
+            const message = getErrorMessage(error);
             return Err(`Mux Gateway balance request failed: ${message}`);
           }
 
@@ -1094,7 +1095,7 @@ export const router = (authToken?: string) => {
           try {
             json = await response.json();
           } catch (error) {
-            const message = error instanceof Error ? error.message : String(error);
+            const message = getErrorMessage(error);
             return Err(`Mux Gateway balance response was not valid JSON: ${message}`);
           }
 
@@ -1315,7 +1316,7 @@ export const router = (authToken?: string) => {
 
             return Ok(undefined);
           } catch (error) {
-            const message = error instanceof Error ? error.message : String(error);
+            const message = getErrorMessage(error);
             return Err(message);
           }
         }),
@@ -2549,7 +2550,7 @@ export const router = (authToken?: string) => {
               log.warn("workspace.getSubagentTranscript: descendant check failed", {
                 requestingWorkspaceId,
                 taskId,
-                error: error instanceof Error ? error.message : String(error),
+                error: getErrorMessage(error),
               });
             }
           }
@@ -3248,7 +3249,7 @@ export const router = (authToken?: string) => {
               await context.sessionTimingService.clearTimingFile(input.workspaceId);
               return { success: true, data: undefined };
             } catch (error) {
-              const message = error instanceof Error ? error.message : String(error);
+              const message = getErrorMessage(error);
               return { success: false, error: message };
             }
           }),
@@ -3288,7 +3289,7 @@ export const router = (authToken?: string) => {
               );
               return { success: true, data: undefined };
             } catch (error) {
-              const message = error instanceof Error ? error.message : String(error);
+              const message = getErrorMessage(error);
               return { success: false, error: message };
             }
           }),

src/node/orpc/server.ts

@@ -24,6 +24,7 @@ import { VERSION } from "@/version";
 import { formatOrpcError } from "@/node/orpc/formatOrpcError";
 import { log } from "@/node/services/log";
 import { attachStreamErrorHandler, isIgnorableStreamError } from "@/node/utils/streamErrors";
+import { getErrorMessage } from "@/common/utils/errors";
 
 type AliveWebSocket = WebSocket & { isAlive?: boolean };
 
@@ -755,7 +756,7 @@ export async function createOrpcServer({
       return;
     }
 
-    const message = error instanceof Error ? error.message : String(error);
+    const message = getErrorMessage(error);
     const code =
       error && typeof error === "object" && "code" in error && typeof error.code === "string"
         ? error.code

src/node/runtime/CoderSSHRuntime.ts

@@ -31,6 +31,7 @@ import { log } from "@/node/services/log";
 import { execBuffered } from "@/node/utils/runtime/helpers";
 import { expandTildeForSSH } from "./tildeExpansion";
 import * as path from "path";
+import { getErrorMessage } from "@/common/utils/errors";
 
 export interface CoderSSHRuntimeConfig extends SSHRuntimeConfig {
   /** Coder-specific configuration */
@@ -333,7 +334,7 @@ export class CoderSSHRuntime extends SSHRuntime {
       emitStatus("ready");
       return { ready: true };
     } catch (error) {
-      const errorMsg = error instanceof Error ? error.message : String(error);
+      const errorMsg = getErrorMessage(error);
 
       emitStatus("error");
 
@@ -445,7 +446,7 @@ export class CoderSSHRuntime extends SSHRuntime {
       if (!coder.existingWorkspace) {
         await this.coderService.disposeProvisioningSession(workspaceName);
       }
-      const message = error instanceof Error ? error.message : String(error);
+      const message = getErrorMessage(error);
       return Err(
         `Failed to read Coder deployment SSH config. ` +
           `Make sure you're logged in with the Coder CLI. ` +
@@ -571,7 +572,7 @@ export class CoderSSHRuntime extends SSHRuntime {
             deletedPath: this.getWorkspacePath(projectPath, workspaceName),
           };
         } catch (error) {
-          const message = error instanceof Error ? error.message : String(error);
+          const message = getErrorMessage(error);
           log.error("Failed to delete stopped Coder workspace", {
             coderWorkspaceName,
             error: message,
@@ -603,7 +604,7 @@ export class CoderSSHRuntime extends SSHRuntime {
       log.debug(`Deleting Coder workspace "${coderWorkspaceName}"`);
       await this.coderService.deleteWorkspace(coderWorkspaceName);
     } catch (error) {
-      const message = error instanceof Error ? error.message : String(error);
+      const message = getErrorMessage(error);
       log.error("Failed to delete Coder workspace", {
         coderWorkspaceName,
         error: message,
@@ -700,7 +701,7 @@ export class CoderSSHRuntime extends SSHRuntime {
           initLogger.logStdout(line);
         }
       } catch (error) {
-        const errorMsg = error instanceof Error ? error.message : String(error);
+        const errorMsg = getErrorMessage(error);
         log.error("Failed to create Coder workspace", { error, config: this.coderConfig });
         initLogger.logStderr(`Failed to create Coder workspace: ${errorMsg}`);
         throw new Error(`Failed to create Coder workspace: ${errorMsg}`);
@@ -746,7 +747,7 @@ export class CoderSSHRuntime extends SSHRuntime {
           initLogger.logStdout(line);
         }
       } catch (error) {
-        const errorMsg = error instanceof Error ? error.message : String(error);
+        const errorMsg = getErrorMessage(error);
         log.error("Failed waiting for Coder workspace", { error, config: this.coderConfig });
         initLogger.logStderr(`Failed connecting to Coder workspace: ${errorMsg}`);
         throw new Error(`Failed connecting to Coder workspace: ${errorMsg}`);
@@ -758,7 +759,7 @@ export class CoderSSHRuntime extends SSHRuntime {
     try {
       await this.coderService.ensureSSHConfig();
     } catch (error) {
-      const errorMsg = error instanceof Error ? error.message : String(error);
+      const errorMsg = getErrorMessage(error);
       log.error("Failed to configure SSH for Coder", { error });
       initLogger.logStderr(`Failed to configure SSH: ${errorMsg}`);
       throw new Error(`Failed to configure SSH for Coder: ${errorMsg}`);

src/node/runtime/DevcontainerRuntime.ts

@@ -254,7 +254,7 @@ export class DevcontainerRuntime extends LocalBaseRuntime {
           } else {
             controller.error(
               new RuntimeError(
-                `Failed to read file ${filePath}: ${err instanceof Error ? err.message : String(err)}`,
+                `Failed to read file ${filePath}: ${getErrorMessage(err)}`,
                 "file_io",
                 err instanceof Error ? err : undefined
               )