diff --git a/server/src/__tests__/environment-run-orchestrator.test.ts b/server/src/__tests__/environment-run-orchestrator.test.ts
index d8273d8498..d81533cbf6 100644
--- a/server/src/__tests__/environment-run-orchestrator.test.ts
+++ b/server/src/__tests__/environment-run-orchestrator.test.ts
@@ -303,6 +303,23 @@ describe("environmentRunOrchestrator — realizeForRun", () => {
     expect(mockResolveEnvironmentExecutionTarget).toHaveBeenCalledOnce();
   });
 
+  it("resolves run-scoped checkout credentials without persisting them in workspace metadata", async () => {
+    const runtime = makeMockRuntime();
+    const orchestrator = environmentRunOrchestrator(mockDb, { environmentRuntime: runtime });
+    const request = mockBuildWorkspaceRealizationRequest.getMockImplementation()!();
+    request.source.repoUrl = "https://github.com/company/private-repo.git";
+    mockBuildWorkspaceRealizationRequest.mockReturnValue(request);
+    const gitAuth = { configArgs: ["-c", "credential.helper="], env: { PAPERCLIP_GIT_TOKEN: "scoped-fixture-token" }, source: "managed_connection" as const, secretName: null };
+    const resolveGitAuth = vi.fn(async () => gitAuth);
+    await orchestrator.realizeForRun({ ...makeRealizeInput({ environment: makeEnvironment("computer") }), resolveGitAuth });
+    expect(resolveGitAuth).toHaveBeenCalledExactlyOnceWith(request.source.repoUrl);
+    expect(runtime.realizeWorkspace).toHaveBeenCalledWith(expect.objectContaining({ gitAuth }));
+    const dispatched = vi.mocked(runtime.realizeWorkspace).mock.calls[0]![0];
+    expect(JSON.stringify(dispatched.workspace)).not.toContain("scoped-fixture-token");
+    expect(JSON.stringify(mockUpdateLeaseMetadata.mock.calls)).not.toContain("scoped-fixture-token");
+    expect(JSON.stringify(mockUpdateExecutionWorkspace.mock.calls)).not.toContain("scoped-fixture-token");
+  });
+
   it("uses an in-place authoritative root on the adapter execution target", async () => {
     mockResolveEnvironmentExecutionTarget.mockResolvedValue({
       kind: "remote",
diff --git a/server/src/modules/computers/adapters/boat.test.ts b/server/src/modules/computers/adapters/boat.test.ts
index d6f96f78bd..7e2240c195 100644
--- a/server/src/modules/computers/adapters/boat.test.ts
+++ b/server/src/modules/computers/adapters/boat.test.ts
@@ -1,5 +1,6 @@
 import {
   mkdtempSync,
+  readFileSync,
   realpathSync,
   rmSync,
   symlinkSync,
@@ -12,6 +13,7 @@ import { spawnSync } from "node:child_process";
 import { remoteProgram } from "./remote-program.js";
 import { afterEach, describe, it, expect, vi } from "vitest";
 import { boatBackend } from "./boat.js";
+import { buildGitAuthInvocation } from "../../../services/git-credentials.js";
 import type { ComputerRecord } from "../domain/ledger.js";
 const record: ComputerRecord = {
   id: "computer",
@@ -112,11 +114,11 @@ function fixture() {
   const temp = realpathSync(mkdtempSync(join(tmpdir(), "computer-files-")));
   roots.push(temp);
   const root = join(temp, "home");
-  const call = (input: Record<string, unknown>) => {
+  const call = (input: Record<string, unknown>, env = process.env) => {
     const result = spawnSync(
       "python3",
       ["-c", remoteProgram.replaceAll("/home/user/paperclip/", `${temp}/`)],
-      { input: JSON.stringify({ ...input, root }), encoding: "utf8" },
+      { input: JSON.stringify({ ...input, root }), encoding: "utf8", env },
     );
     if (result.status !== 0) throw new Error(result.stderr);
     return JSON.parse(result.stdout);
@@ -218,6 +220,40 @@ describe("confined computer files", () => {
     expect(f.call({ action: "list", limit: 2 }).entries).toHaveLength(2);
     expect(f.call({ action: "list", limit: 1001 })).toEqual({ error: "invalid" });
   });
+  it("clones a private checkout with operation-scoped auth and leaves no credential material behind", () => {
+    const f = fixture();
+    const source = join(f.temp, "source");
+    mkdirSync(source);
+    const realGit = spawnSync("which", ["git"], { encoding: "utf8" }).stdout.trim();
+    for (const args of [["init"], ["-c", "user.name=Test", "-c", "user.email=test@example.com", "commit", "--allow-empty", "-m", "base"]]) {
+      expect(spawnSync(realGit, args, { cwd: source, encoding: "utf8" }).status).toBe(0);
+    }
+    const bin = join(f.temp, "bin");
+    mkdirSync(bin);
+    // Stand in for an authenticated GitHub transport, using real Git and the
+    // production URL-scoped credential helper, without any external network.
+    writeFileSync(join(bin, "git"), `#!${process.execPath}
+const {spawnSync}=require("node:child_process");
+const args=process.argv.slice(2), clone=args.indexOf("clone");
+if(clone<0) process.exit(9);
+if(args.some(arg=>arg.includes("scoped-fixture-token"))) process.exit(10);
+const credential=spawnSync(process.env.FIXTURE_REAL_GIT,[...args.slice(0,clone),"credential","fill"],{input:"protocol=https\\nhost=github.com\\n\\n",encoding:"utf8"});
+if(credential.status!==0||!credential.stdout.includes("password=scoped-fixture-token")) process.exit(11);
+args[clone+2]=process.env.FIXTURE_SOURCE;
+const result=spawnSync(process.env.FIXTURE_REAL_GIT,args,{encoding:"utf8"});
+process.stdout.write(result.stdout||"");process.stderr.write(result.stderr||"");process.exit(result.status??1);
+`, { mode: 0o700 });
+    const env = { ...process.env, PATH: `${bin}:${process.env.PATH}`, FIXTURE_REAL_GIT: realGit, FIXTURE_SOURCE: source };
+    const request = { action: "workspace", mode: "shared", repositoryUrl: "https://github.com/company/private.git" };
+    expect(f.call(request, env)).toEqual({ error: "command_failed" });
+    const gitAuth = buildGitAuthInvocation({ token: "scoped-fixture-token", source: "managed_connection", secretName: null });
+    const result = f.call({ ...request, gitAuth }, env);
+    expect(result.remoteCwd).toBe(join(f.root, "checkout"));
+    const config = readFileSync(join(result.remoteCwd, ".git", "config"), "utf8");
+    expect(config).not.toContain("scoped-fixture-token");
+    expect(config).not.toContain("credential");
+    expect(spawnSync(realGit, ["rev-parse", "HEAD"], { cwd: result.remoteCwd }).status).toBe(0);
+  });
   it.each([false, true])("uses the requested worktree branch separately from its start ref (explicit base: %s)", explicitBase => {
     const f = fixture();
     const checkout = join(f.root, "checkout");
diff --git a/server/src/modules/computers/adapters/remote-program.ts b/server/src/modules/computers/adapters/remote-program.ts
index 2f658d45fb..fa937dbf40 100644
--- a/server/src/modules/computers/adapters/remote-program.ts
+++ b/server/src/modules/computers/adapters/remote-program.ts
@@ -5,8 +5,8 @@ p=json.load(sys.stdin)
 def fail(code):
  print(json.dumps({'error':code}));sys.exit(0)
 def digest(data):return hashlib.sha256(data).hexdigest()
-def run(args,cwd=None):
- r=subprocess.run(args,cwd=cwd,capture_output=True,text=True)
+def run(args,cwd=None,env=None):
+ r=subprocess.run(args,cwd=cwd,env=env,capture_output=True,text=True)
  if r.returncode:fail('command_failed')
  return r.stdout.strip()
 root=p['root']
@@ -65,7 +65,13 @@ if act=='workspace':
  checkout=os.path.join(root,'checkout')
  if repo:
   if not (repo.startswith('https://') or repo.startswith('ssh://') or repo.startswith('git@')) or '\n' in repo:fail('invalid')
-  if not os.path.exists(checkout):run(['git','clone','--',repo,checkout])
+  if not os.path.exists(checkout):
+   # Resolve credentials on the controller for this operation. Only the clone
+   # child receives the helper environment; no credential file or Git config persists.
+   auth=p.get('gitAuth') or {};git_env=dict(os.environ)
+   git_env.update({'GIT_TERMINAL_PROMPT':'0','GIT_CONFIG_GLOBAL':'/dev/null','GIT_CONFIG_NOSYSTEM':'1'})
+   git_env.update(auth.get('env',{}))
+   run(['git']+auth.get('configArgs',[])+['clone','--',repo,checkout],env=git_env)
   elif run(['git','remote','get-url','origin'],checkout)!=repo:fail('conflict')
  else:
   os.makedirs(checkout,exist_ok=True)
diff --git a/server/src/modules/computers/application/service.test.ts b/server/src/modules/computers/application/service.test.ts
index fa962a6158..80be803a88 100644
--- a/server/src/modules/computers/application/service.test.ts
+++ b/server/src/modules/computers/application/service.test.ts
@@ -113,6 +113,16 @@ function fixture() {
   };
 }
 describe("computer ownership", () => {
+  it("passes checkout credentials transiently without retaining them in computer state", async () => {
+    const f = fixture();
+    await f.attach();
+    const binding = await f.admit();
+    const gitAuth = { configArgs: ["-c", "credential.helper="], env: { PAPERCLIP_GIT_TOKEN: "scoped-fixture-token" } };
+    await f.service.realizeWorkspace({ ...f.scope, owner: binding.owner, projectId: "project", mode: "shared",
+      repositoryUrl: "https://github.com/company/private.git", gitAuth });
+    expect(f.backend.remote).toHaveBeenCalledWith(expect.anything(), expect.objectContaining({ action: "workspace", gitAuth }));
+    expect(JSON.stringify(await f.repository.get(f.scope))).not.toContain("scoped-fixture-token");
+  });
   it("explains an unavailable dev server without masking provider errors", async () => {
     const f = fixture();
     await f.attach();
diff --git a/server/src/modules/computers/application/service.ts b/server/src/modules/computers/application/service.ts
index 44e4d7602d..64e1e8c37c 100644
--- a/server/src/modules/computers/application/service.ts
+++ b/server/src/modules/computers/application/service.ts
@@ -767,6 +767,8 @@ finally:
       projectId?: string;
       taskId?: string;
       repositoryUrl?: string;
+      /** Transient Git helper configuration; sent over stdin, never retained in the ledger. */
+      gitAuth?: { configArgs: string[]; env: Record<string, string> };
       branch?: string;
       baseRef?: string;
       mode: "shared" | "worktree";
diff --git a/server/src/services/computer-environment-driver.ts b/server/src/services/computer-environment-driver.ts
index b89e70dffc..9818dc8fc7 100644
--- a/server/src/services/computer-environment-driver.ts
+++ b/server/src/services/computer-environment-driver.ts
@@ -77,11 +77,12 @@ export function createComputerEnvironmentDriver(db: Db): EnvironmentRuntimeDrive
       if (!result.retired) throw new Error("computer_owner_retirement_superseded");
       return { providerLeaseId: lease.providerLeaseId, state: "stopped" };
     },
-    async realizeWorkspace({ lease, workspace }) {
+    async realizeWorkspace({ lease, workspace, gitAuth }) {
       const request = workspace.metadata?.workspaceRealizationRequest as { source?: { projectId?: string; repoUrl?: string; repoRef?: string; branchName?: string; strategy?: string }; issueId?: string } | undefined;
       const result = await computers.realizeWorkspace({ ...scope(lease), owner: computerOwnerFromLease(lease),
         projectId: request?.source?.projectId ?? undefined, taskId: request?.issueId ?? undefined,
         repositoryUrl: request?.source?.repoUrl ?? undefined,
+        gitAuth,
         branch: request?.source?.branchName ?? request?.source?.repoRef ?? undefined,
         baseRef: request?.source?.repoRef ?? undefined,
         mode: request?.source?.strategy === "git_worktree" ? "worktree" : "shared" });
diff --git a/server/src/services/environment-run-orchestrator.ts b/server/src/services/environment-run-orchestrator.ts
index 82d7997efc..c5cbb0ab95 100644
--- a/server/src/services/environment-run-orchestrator.ts
+++ b/server/src/services/environment-run-orchestrator.ts
@@ -51,6 +51,7 @@ import { buildWorkspaceRealizationRequest } from "./workspace-realization.js";
 import { executionWorkspaceService } from "./execution-workspaces.js";
 import { logActivity } from "./activity-log.js";
 import { logger } from "../middleware/logger.js";
+import type { GitRemoteAuthProvider } from "./git-credentials.js";
 import { parseObject } from "../adapters/utils.js";
 import type { RealizedExecutionWorkspace } from "./workspace-runtime.js";
 import type { PluginWorkerManager } from "./plugin-worker-manager.js";
@@ -393,6 +394,8 @@ export function environmentRunOrchestrator(
      * target. Absent keeps the safe no-op default in the bridge.
      */
     duplexObservabilityRecorder?: DuplexObservabilityRecorder | null;
+    /** Run-scoped auth for initial persistent checkouts; never persisted as workspace metadata. */
+    resolveGitAuth?: GitRemoteAuthProvider;
   }): Promise<EnvironmentRealizationResult> {
     const {
       environment,
@@ -430,6 +433,9 @@ export function environmentRunOrchestrator(
         const workspaceRealizationResult = await environmentRuntime.realizeWorkspace({
           environment,
           lease,
+          gitAuth: environment.driver === "computer" && workspaceRealizationRequest.source.repoUrl
+            ? await input.resolveGitAuth?.(workspaceRealizationRequest.source.repoUrl) ?? undefined
+            : undefined,
           workspace: {
             localPath: executionWorkspace.cwd,
             remotePath: remoteCwd,
diff --git a/server/src/services/environment-runtime.ts b/server/src/services/environment-runtime.ts
index 94558bb4dd..b3a93ca67d 100644
--- a/server/src/services/environment-runtime.ts
+++ b/server/src/services/environment-runtime.ts
@@ -526,6 +526,8 @@ export interface EnvironmentDriverLeaseInput {
 }
 
 export interface EnvironmentDriverRealizeWorkspaceInput extends EnvironmentDriverLeaseInput {
+  /** Ephemeral authentication for the initial checkout, excluded from durable metadata. */
+  gitAuth?: { configArgs: string[]; env: Record<string, string> };
   workspace: {
     localPath?: string;
     remotePath?: string;
diff --git a/server/src/services/heartbeat.ts b/server/src/services/heartbeat.ts
index ba705de655..c6c7cbe50c 100644
--- a/server/src/services/heartbeat.ts
+++ b/server/src/services/heartbeat.ts
@@ -4529,6 +4529,7 @@ export function heartbeatService(
           effectiveExecutionWorkspaceMode,
           persistedExecutionWorkspace,
           duplexObservabilityRecorder,
+          resolveGitAuth: workspaceGitAuthProvider,
         });
         nativeRunnerPreparationSpans.push({
           name: "environment.workspace.realize",