diff --git a/apps/server/src/provider/ClaudeProvider.ts b/apps/server/src/provider/ClaudeProvider.ts
index 8bc961834f270ee3027d7cc7e41a1d1734d8cb73..6d53c7c79c994c72e7b1a6ae25e3dcf530eac152 100644
--- a/apps/server/src/provider/ClaudeProvider.ts
+++ b/apps/server/src/provider/ClaudeProvider.ts
@@ -455,6 +455,7 @@ const runClaudeCommand = Effect.fn("runClaudeCommand")(function* (
   claudeSettings: ClaudeSettings,
   args: ReadonlyArray<string>,
   environment?: NodeJS.ProcessEnv,
+  cwd?: string,
 ) {
   const claudeEnvironment = yield* makeClaudeEnvironment(claudeSettings, environment);
   const spawnCommand = yield* resolveSpawnCommand(claudeSettings.binaryPath, args, {
@@ -463,6 +464,7 @@ const runClaudeCommand = Effect.fn("runClaudeCommand")(function* (
   const command = ChildProcess.make(spawnCommand.command, spawnCommand.args, {
     env: claudeEnvironment,
     shell: spawnCommand.shell,
+    ...(cwd ? { cwd } : {}),
   });
   return yield* spawnAndCollect(claudeSettings.binaryPath, command);
 });
@@ -533,6 +535,7 @@ export const checkClaudeProviderStatus = Effect.fn("checkClaudeProviderStatus")(
     claudeSettings,
     ["--version"],
     resolvedEnvironment,
+    cwd,
   ).pipe(Effect.timeoutOption(DEFAULT_TIMEOUT_MS), Effect.result);
 
   if (Result.isFailure(versionProbe)) {
diff --git a/apps/server/src/provider/Drivers/ClaudeDriver.ts b/apps/server/src/provider/Drivers/ClaudeDriver.ts
index 0169eb87ba7618d38842334795f2700041d512b9..a379280969ae6756d6b31eeb9bd7e04bfe801061 100644
--- a/apps/server/src/provider/Drivers/ClaudeDriver.ts
+++ b/apps/server/src/provider/Drivers/ClaudeDriver.ts
@@ -123,7 +123,11 @@ export const ClaudeDriver: ProviderDriver<ClaudeSettings, ClaudeDriverEnv, Path.
       const spawner = yield* ChildProcessSpawner.ChildProcessSpawner;
       const fileSystem = yield* FileSystem.FileSystem;
       const path = yield* Path.Path;
-      const { cwd } = yield* ServerConfig.ServerConfig;
+      // Instance-level probes are not tied to a project, so they run in the
+      // server's own state dir. The server cwd is $HOME in packaged desktop
+      // builds, and `claude` wrappers that scope themselves to their cwd refuse
+      // to run there. Workspace probes use the thread cwd via `snapshotForCwd`.
+      const { stateDir } = yield* ServerConfig.ServerConfig;
       const httpClient = yield* HttpClient.HttpClient;
       const latestVersions = yield* ProviderLatestVersions.ProviderLatestVersions;
       const resetCreditCoordinator = yield* ResetCreditCoordinator.ResetCreditCoordinator;
@@ -204,7 +208,7 @@ export const ClaudeDriver: ProviderDriver<ClaudeSettings, ClaudeDriverEnv, Path.
         timeToLive: CAPABILITIES_PROBE_TTL,
         lookup: () =>
           Effect.all([
-            probeClaudeCapabilities(effectiveConfig, processEnv, cwd),
+            probeClaudeCapabilities(effectiveConfig, processEnv, stateDir),
             ClaudeResetCredits.readClaudeOrganizationId(accountConfigPath),
           ]).pipe(
             Effect.map(([capabilities, workspaceId]) =>
@@ -216,7 +220,7 @@ export const ClaudeDriver: ProviderDriver<ClaudeSettings, ClaudeDriverEnv, Path.
       });
       const capabilitiesCacheKey = yield* makeClaudeCapabilitiesCacheKey(
         effectiveConfig,
-        cwd,
+        stateDir,
         processEnv,
       );
 
@@ -230,7 +234,7 @@ export const ClaudeDriver: ProviderDriver<ClaudeSettings, ClaudeDriverEnv, Path.
                 effectiveConfig,
                 () => Cache.get(capabilitiesProbeCache, capabilitiesCacheKey),
                 processEnv,
-                cwd,
+                stateDir,
                 catalog,
                 scopedLimitNames,
                 (version) =>
diff --git a/apps/server/src/provider/ProviderInstanceRegistry.test.ts b/apps/server/src/provider/ProviderInstanceRegistry.test.ts
index cc400c170f4adbaf86115b2d7b63a8a929f41b35..eb3dc4109b851de3298e1f3c258b03203d87b280 100644
--- a/apps/server/src/provider/ProviderInstanceRegistry.test.ts
+++ b/apps/server/src/provider/ProviderInstanceRegistry.test.ts
@@ -437,6 +437,40 @@ describe("ProviderInstanceRegistry — multi-instance codex slice", () => {
     }).pipe(Effect.provide(layerTest)),
   );
 
+  it.live("runs Claude instance probes in the server state dir, not the server cwd", () =>
+    Effect.gen(function* () {
+      if (yield* HostProcess.isWindows) return;
+
+      const fixtures = yield* makeTildeProviderFixtures();
+      const { stateDir } = yield* ServerConfig.ServerConfig;
+      const claudeId = ProviderInstanceId.make("claude_state_dir");
+      const { registry } = yield* makeProviderInstanceRegistry<ClaudeDriverEnv>({
+        drivers: [ClaudeDriver],
+        configMap: {
+          [claudeId]: {
+            driver: ProviderDriverKind.make("claudeAgent"),
+            enabled: true,
+            // Packaged desktop builds start the server in $HOME, where some
+            // `claude` wrappers refuse to run.
+            environment: [{ name: "T3_CLAUDE_REQUIRED_CWD", value: stateDir, sensitive: false }],
+            config: makeClaudeConfig({
+              enabled: true,
+              binaryPath: fixtures.claudeBinaryPath,
+              homePath: fixtures.claudeHomePath,
+            }),
+          },
+        },
+      });
+      const claude = yield* registry.getInstance(claudeId);
+
+      expect(yield* claude!.snapshot.refresh).toMatchObject({
+        status: "ready",
+        version: "2.1.219",
+        auth: { status: "authenticated" },
+      });
+    }).pipe(Effect.provide(layerTest)),
+  );
+
   const redeemClaudeReset = (claim: { result: string; usageFailsAfterClaim: boolean }) =>
     Effect.gen(function* () {
       const fs = yield* FileSystem.FileSystem;
diff --git a/apps/server/src/provider/testing/ProviderInstanceRegistryLive.fixture.mjs b/apps/server/src/provider/testing/ProviderInstanceRegistryLive.fixture.mjs
index 054ca04703e5149b7219d45708e0c3ed824557bf..1726bceeab6236e7e1fac6b5857f841847625f26 100755
--- a/apps/server/src/provider/testing/ProviderInstanceRegistryLive.fixture.mjs
+++ b/apps/server/src/provider/testing/ProviderInstanceRegistryLive.fixture.mjs
@@ -1,6 +1,12 @@
 #!/usr/bin/env node
 import * as NodeFS from "node:fs";
 import * as NodeReadline from "node:readline";
+// Opt-in: act like a `claude` wrapper that only runs inside one directory.
+const requiredCwd = process.env.T3_CLAUDE_REQUIRED_CWD;
+if (requiredCwd && process.cwd() !== NodeFS.realpathSync(requiredCwd)) {
+  process.stderr.write(`claude: refusing to run outside ${requiredCwd}\n`);
+  process.exit(1);
+}
 if (process.argv.includes("--version")) {
   process.stdout.write("claude 2.1.219\n");
   process.exit(0);