diff --git a/doc/plans/2026-10-20-dependable-everyday-work.md b/doc/plans/2026-10-20-dependable-everyday-work.md
index 37dfea634ce..e1ce750356d 100644
--- a/doc/plans/2026-10-20-dependable-everyday-work.md
+++ b/doc/plans/2026-10-20-dependable-everyday-work.md
@@ -96,3 +96,18 @@ E2E support checks pass 38. Server, runner, and E2E typechecks pass. Copilot v54
 binds the changed shared completion guidance; v53 remains a historical identity.
 The three development pilot failures remain retained. These checks do not count
 as the required staging matrix, and a fresh provider run remains necessary.
+
+The fourth development attempt reached a successor through a monitor fallback,
+then failed before provider startup while applying Git exclusions to the task
+root. It is a failure of the required same-agent journey, even though a successor
+started. The log records Git's exact non-repository error. A real-Git and database
+reproduction shows the same error for a declared plain task directory containing
+inert Git metadata. The original attempt did not retain that metadata's contents
+or establish which component created it.
+
+The next narrow repair lets only an explicitly declared plain task root proceed
+past Git's exact non-repository result. It leaves the existing files intact.
+Configured checkouts keep strict validation, real Git roots still receive the
+exclusion, linked metadata stays rejected, and missing Git stays an error. The
+repair's Git and authorization cohort passes locally. Fresh provider
+remeasurement and the monitor-fallback defect remain open.
diff --git a/server/src/__tests__/managed-repository-checkout.test.ts b/server/src/__tests__/managed-repository-checkout.test.ts
index 26c10afa7b2..2767407786e 100644
--- a/server/src/__tests__/managed-repository-checkout.test.ts
+++ b/server/src/__tests__/managed-repository-checkout.test.ts
@@ -1,14 +1,14 @@
 import { execFile as execFileCallback } from "node:child_process";
 import { promisify } from "node:util";
-import { mkdtemp, mkdir, writeFile, readFile, readdir, rm, stat } from "node:fs/promises";
+import { mkdtemp, mkdir, writeFile, readFile, readdir, rm, stat, symlink } from "node:fs/promises";
 import { tmpdir } from "node:os";
 import path from "node:path";
-import { afterEach, describe, expect, it } from "vitest";
+import { afterEach, describe, expect, it, vi } from "vitest";
 import { materializeManagedProjectWorkspace, ensureManagedRepositoriesIgnored } from "../services/managed-repository-checkout.js";
 
 const execFile = promisify(execFileCallback);
 const directories: string[] = [];
-afterEach(async () => { await Promise.all(directories.splice(0).map(dir => rm(dir, { recursive: true, force: true }))); });
+afterEach(async () => { vi.unstubAllEnvs(); await Promise.all(directories.splice(0).map(dir => rm(dir, { recursive: true, force: true }))); });
 async function fixture() {
   const root = await mkdtemp(path.join(tmpdir(), "paperclip-repository-publication-"));
   directories.push(root);
@@ -33,6 +33,34 @@ describe("atomic managed repository publication", () => {
     await ensureManagedRepositoriesIgnored(source);
     expect(await readFile(path.join(source, ".git", "info", "exclude"), "utf8")).toContain("/.paperclip-repositories/");
   });
+  it("allows a declared plain task directory with inert Git metadata without changing its files", async () => {
+    const { target } = await fixture();
+    await mkdir(path.join(target, ".git", "info"), { recursive: true });
+    const file = path.join(target, ".git", "info", "exclude");
+    await writeFile(file, "/.paperclip-repositories/\n");
+    await expect(ensureManagedRepositoriesIgnored(target, { plainTaskDirectory: true })).resolves.toBeUndefined();
+    expect(await readFile(file, "utf8")).toBe("/.paperclip-repositories/\n");
+    await expect(ensureManagedRepositoriesIgnored(target)).rejects.toThrow("not a git repository");
+  });
+  it("still excludes managed repositories when a task directory contains a real checkout", async () => {
+    const { source } = await fixture();
+    await ensureManagedRepositoriesIgnored(source, { plainTaskDirectory: true });
+    expect(await readFile(path.join(source, ".git", "info", "exclude"), "utf8")).toContain("/.paperclip-repositories/");
+  });
+  it("retains unexpected Git errors for declared plain task directories", async () => {
+    const { root, target } = await fixture();
+    await mkdir(path.join(target, ".git"), { recursive: true });
+    vi.stubEnv("PATH", path.join(root, "missing-git"));
+    await expect(ensureManagedRepositoriesIgnored(target, { plainTaskDirectory: true })).rejects.toMatchObject({ code: "ENOENT" });
+  });
+  it("rejects linked Git metadata even for a declared plain task directory", async () => {
+    const { source, target } = await fixture();
+    await mkdir(target);
+    await symlink(path.join(source, ".git"), path.join(target, ".git"), "dir");
+    const original = await readFile(path.join(source, ".git", "info", "exclude"), "utf8");
+    await expect(ensureManagedRepositoriesIgnored(target, { plainTaskDirectory: true })).rejects.toThrow("must not be a symlink");
+    expect(await readFile(path.join(source, ".git", "info", "exclude"), "utf8")).toBe(original);
+  });
   it("writes the pinned receipt inside the clone before making it visible", async () => {
     const { source, target } = await fixture();
     const result = await materializeManagedProjectWorkspace(target, { repoUrl: "https://github.com/test/source", localSource: source, beforePublish: async clone => {
diff --git a/server/src/__tests__/task-workspace-repositories-trust.test.ts b/server/src/__tests__/task-workspace-repositories-trust.test.ts
index b33426f6a56..00e5587f823 100644
--- a/server/src/__tests__/task-workspace-repositories-trust.test.ts
+++ b/server/src/__tests__/task-workspace-repositories-trust.test.ts
@@ -33,7 +33,7 @@ const support = await getEmbeddedPostgresTestSupport();
   let db: ReturnType<typeof createDb>;
   let root: string;
   beforeAll(async () => { ({ db, root } = await context.setup()); }, EMBEDDED_POSTGRES_TEST_TIMEOUT_MS);
-  afterEach(() => { vi.clearAllMocks(); vi.restoreAllMocks(); });
+  afterEach(() => { acquisition.materialize.mockReset(); vi.clearAllMocks(); vi.restoreAllMocks(); });
   afterAll(context.cleanup);
   const { fixture, lowTrustPeer, standardPeer, privateTask, localPrivateClone } = context;
 
@@ -334,7 +334,7 @@ const support = await getEmbeddedPostgresTestSupport();
     expect(acquisition.materialize).not.toHaveBeenCalled();
   });
 
-  it.each(["sponsored", "local_board", "local_board_jwt", "routine"] as const)("prepares public Git from an idle workspace for a trusted %s task and reuses verified bytes after trust downgrade", async principal => {
+  it.each(["sponsored", "sponsored_git_residue", "local_board", "local_board_jwt", "routine"] as const)("prepares public Git from an idle workspace for a trusted %s task and reuses verified bytes after trust downgrade", async principal => {
     const f = await fixture();
     await db.update(executionWorkspaces).set({ status: "idle" }).where(eq(executionWorkspaces.id, f.workspace.id));
     const localBoard = principal === "local_board" || principal === "local_board_jwt";
@@ -367,6 +367,10 @@ const support = await getEmbeddedPostgresTestSupport();
       await exec("git", ["-C", cwd, "remote", "set-url", "origin", input.repoUrl]);
       return result;
     });
+    if (principal === "sponsored_git_residue") {
+      await mkdir(path.join(f.admission.cwd, ".git", "info"), { recursive: true });
+      await writeFile(path.join(f.admission.cwd, ".git", "info", "exclude"), "/.paperclip-repositories/\n");
+    }
     const [prepared] = await f.service.prepareForAdmission(admission);
     expect(prepared.id).toBe(receipt.operationId);
     expect(await readFile(path.join(prepared.cwd, "public.txt"), "utf8")).toBe("Public fixture bytes\n");
diff --git a/server/src/services/execution-workspace-repositories.ts b/server/src/services/execution-workspace-repositories.ts
index f0eec1af1b3..4c2cb2c07ed 100644
--- a/server/src/services/execution-workspace-repositories.ts
+++ b/server/src/services/execution-workspace-repositories.ts
@@ -318,7 +318,7 @@ export function executionWorkspaceRepositoryService(db: Db) {
     return candidatePin;
   }
   async function prepareForAdmission(input: { companyId: string; issueId: string; workspaceId: string; cwd: string; agentId: string; runId: string; responsibleUserId: string | null }) {
-    const { acquisitionRestricted } = await publicationBinding(db, input, false);
+    const { acquisitionRestricted, workspace } = await publicationBinding(db, input, false);
     const rows = await list(input.companyId, input.workspaceId);
     if (!rows.length) return [];
     await publicationBinding(db, input);
@@ -361,7 +361,9 @@ export function executionWorkspaceRepositoryService(db: Db) {
           await fs.writeFile(ignoreTemporary, "*\n", { flag: "wx", mode: 0o600 });
           await fs.rename(ignoreTemporary, ignorePath);
         } finally { await fs.rm(ignoreTemporary, { force: true }); }
-        await measureRunPhase("workspace.repository.ignore_rules", () => ensureManagedRepositoriesIgnored(root));
+        await measureRunPhase("workspace.repository.ignore_rules", () => ensureManagedRepositoriesIgnored(root, {
+          plainTaskDirectory: workspace.strategyType === "task_directory" && !workspace.repoUrl && !workspace.projectWorkspaceId,
+        }));
       }
       return stagingParent;
     });
diff --git a/server/src/services/managed-repository-checkout.ts b/server/src/services/managed-repository-checkout.ts
index 3d5dd027c0f..3d18bb49769 100644
--- a/server/src/services/managed-repository-checkout.ts
+++ b/server/src/services/managed-repository-checkout.ts
@@ -162,12 +162,23 @@ export async function materializeManagedProjectWorkspace(
 }
 
 
-export async function ensureManagedRepositoriesIgnored(cwd: string): Promise<void> {
+export async function ensureManagedRepositoriesIgnored(cwd: string, options: { plainTaskDirectory?: boolean } = {}): Promise<void> {
   const gitEntry = await fs.lstat(path.join(cwd, ".git")).catch(() => null);
   if (!gitEntry) return;
   if (gitEntry.isSymbolicLink()) throw new Error("Workspace Git metadata must not be a symlink");
-  const excludePath = await execFile("git", ["-C", cwd, "rev-parse", "--git-path", "info/exclude"], { timeout: 10_000 })
-    .then((result) => path.resolve(cwd, result.stdout.trim()));
+  let excludePath: string;
+  try {
+    const result = await execFile("git", ["-C", cwd, "rev-parse", "--git-path", "info/exclude"], {
+      timeout: 10_000, env: { ...process.env, LC_ALL: "C" },
+    });
+    excludePath = path.resolve(cwd, result.stdout.trim());
+  } catch (error) {
+    const failure = error as { code?: unknown; signal?: unknown; stderr?: unknown };
+    if (options.plainTaskDirectory && failure.code === 128 && failure.signal == null &&
+        failure.stderr === "fatal: not a git repository (or any of the parent directories): .git\n" &&
+        !process.env.GIT_DIR && !process.env.GIT_WORK_TREE && !process.env.GIT_COMMON_DIR) return;
+    throw error;
+  }
   const exclude = await fs.readFile(excludePath, "utf8").catch(() => "");
   if (!exclude.split(/\r?\n/).includes(`/${PROJECT_REPOSITORIES_DIR}/`)) {
     await fs.mkdir(path.dirname(excludePath), { recursive: true });