diff --git a/package.json b/package.json
index 4d2e27d67..1b7426b98 100644
--- a/package.json
+++ b/package.json
@@ -33,7 +33,7 @@
     "test:node-pty-permissions": "node --import tsx --test src/node-pty-postinstall.test.ts",
     "test:physical-host-registry": "tsx src/physical-host-registry.test.ts",
     "start": "node dist/cli.js serve",
-    "test": "node scripts/check-test-chain.mjs && tsx src/local-agent-path.test.ts && npm run test:node-pty-permissions && tsx src/development-boundaries.test.ts && npm run test:physical-host-registry && npm run test:carrier-binding && tsx src/coordination-reader-loader.test.ts && tsx src/control-plane-ownership.test.ts && tsx src/control-plane-handoff.test.ts && tsx src/control-plane-continuation.test.ts && tsx src/deployment-convergence.test.ts && tsx src/capability-generation-convergence.test.ts && tsx src/control-plane-convergence.test.ts && tsx src/current-completion-matrix.test.ts && tsx src/control-plane-consumer.test.ts && tsx src/local-agent-cline-catalog.test.ts && tsx src/chat-swarm-contract.test.ts && tsx src/chat-swarm-store.test.ts && tsx src/chat-swarm-runtime-owner.test.ts && tsx src/chat-swarm-runtime-tools.test.ts && tsx src/local-agent-opencode-mcp-catalog.test.ts && tsx src/chat-swarm-coordinator.test.ts && tsx src/chat-swarm-peer-runtime.test.ts && tsx src/chat-swarm-tools.test.ts && tsx src/chat-swarm-lifecycle.test.ts && tsx src/chat-swarm-carrier.test.ts && tsx src/chat-swarm-continuation-domain.test.ts && tsx src/chat-swarm-continuation-store.test.ts && tsx src/chat-swarm-peer-admission.test.ts && tsx src/chat-swarm-task-ledger.test.ts && tsx src/git-worktrees.test.ts && tsx src/host-storage-retention.test.ts && tsx src/execution-protocol.test.ts && tsx src/durable-operations-ci.test.ts && tsx src/git-candidate.test.ts && tsx src/config.test.ts && tsx src/onboarding.test.ts && tsx src/cli-workspace.test.ts && tsx src/request-meta.test.ts && tsx src/incoming-artifacts.test.ts && tsx src/artifact-download.test.ts && tsx src/ui/card-types.test.ts && tsx src/ui/patch-display.test.ts && tsx src/ui/tool-display.test.ts && tsx src/apply-patch.test.ts && tsx src/process-platform.test.ts && tsx src/process-sessions-ci.test.ts && tsx src/codex-goal-sessions-ci.test.ts && tsx src/local-agent-process-tree.test.ts && tsx src/mcp-sessions.test.ts && tsx src/cutover-state.test.ts && tsx src/cutover-activation.test.ts && tsx src/cutover-state-recovery-guard.test.ts && tsx src/cutover-build-ready.test.ts && tsx src/cutover-orchestration.test.ts && tsx src/mcp-cutover.test.ts && tsx src/cutover-restart.test.ts && tsx src/cutover-http.test.ts && tsx src/cutover-recovery.test.ts && tsx src/cutover-binding-repair.test.ts && tsx src/capability-manifest.test.ts && tsx src/server-shutdown.test.ts && tsx src/codex-runtime.test.ts && tsx src/local-agent-config.test.ts && tsx src/local-agent-catalog.test.ts && tsx src/local-agent-presentation.test.ts && tsx src/local-agent-runtime.test.ts && tsx src/local-agent-daemon-lifecycle.test.ts && tsx src/local-agent-daemon-protocol.test.ts && tsx src/local-agent-daemon.test.ts && tsx src/local-agent-codex.test.ts && tsx src/local-agent-opencode.test.ts && tsx src/local-agent-opencode-catalog.test.ts && tsx src/local-agent-acp.test.ts && tsx src/local-agent-grok.test.ts && tsx src/local-agent-pi-sandbox.test.ts && tsx src/local-agent-pi.test.ts && tsx src/local-agent-claude.test.ts && tsx src/local-agent-adapters.test.ts && tsx src/local-agent-availability.test.ts && tsx src/herdr-socket-path.test.ts && tsx src/local-agent-profiles.test.ts && tsx src/local-agent-profile-source.test.ts && tsx src/local-agent-targets.test.ts && tsx src/local-agent-toolchains.test.ts && tsx src/local-agent-idle-policy.test.ts && tsx src/local-agent-capacity.test.ts && tsx src/local-agent-execution-contract.test.ts && tsx src/local-agent-continuation.test.ts && tsx src/provider-scratch.test.ts && tsx src/git-integration-ci.test.ts && tsx src/repository-intelligence.test.ts && tsx src/local-agent-store.test.ts && tsx src/local-agent-manager.test.ts && tsx src/roots.test.ts && tsx src/skills.test.ts && tsx src/workspaces.test.ts && tsx src/workspace-conversation.test.ts && tsx src/conversation-isolation.test.ts && tsx src/review-checkpoints.test.ts && tsx src/server-ci.test.ts && tsx src/oauth-store.test.ts && tsx src/cli-ci.test.ts && tsx src/oauth-json-and-child-reap.test.ts && tsx src/local-agent-errors.test.ts && tsx src/provider-output-redaction.test.ts && tsx src/host-activation.test.ts && tsx src/host-operation-policy.test.ts && tsx src/host-operations.test.ts && tsx src/host-operations-http.test.ts && tsx src/host-operation-external.test.ts && node --import tsx --test src/issue-413-wave1.test.ts && node --import tsx --test src/work-resume-integration.test.ts && tsx src/batch-autonomy-grant.test.ts && node --import tsx --test src/db/migrations.test.ts && node --import tsx --test src/host-capability-snapshot.test.ts && node --import tsx --test src/pi-tools.test.ts && node --import tsx --test src/work-resume.test.ts",
+    "test": "node scripts/check-test-chain.mjs && tsx src/local-agent-path.test.ts && npm run test:node-pty-permissions && tsx src/development-boundaries.test.ts && npm run test:physical-host-registry && npm run test:carrier-binding && tsx src/coordination-reader-loader.test.ts && tsx src/control-plane-ownership.test.ts && tsx src/control-plane-handoff.test.ts && tsx src/control-plane-continuation.test.ts && tsx src/deployment-convergence.test.ts && tsx src/capability-generation-convergence.test.ts && tsx src/control-plane-convergence.test.ts && tsx src/current-completion-matrix.test.ts && tsx src/control-plane-consumer.test.ts && tsx src/local-agent-cline-catalog.test.ts && tsx src/chat-swarm-contract.test.ts && tsx src/chat-swarm-store.test.ts && tsx src/chat-swarm-runtime-owner.test.ts && tsx src/chat-swarm-runtime-tools.test.ts && tsx src/local-agent-opencode-mcp-catalog.test.ts && tsx src/chat-swarm-coordinator.test.ts && tsx src/chat-swarm-peer-runtime.test.ts && tsx src/chat-swarm-tools.test.ts && tsx src/chat-swarm-lifecycle.test.ts && tsx src/chat-swarm-carrier.test.ts && tsx src/chat-swarm-continuation-domain.test.ts && tsx src/chat-swarm-continuation-store.test.ts && tsx src/chat-swarm-peer-admission.test.ts && tsx src/chat-swarm-task-ledger.test.ts && tsx src/git-worktrees.test.ts && tsx src/tool-projection-recovery.test.ts && tsx src/host-storage-retention.test.ts && tsx src/execution-protocol.test.ts && tsx src/durable-operations-ci.test.ts && tsx src/git-candidate.test.ts && tsx src/config.test.ts && tsx src/onboarding.test.ts && tsx src/cli-workspace.test.ts && tsx src/request-meta.test.ts && tsx src/incoming-artifacts.test.ts && tsx src/artifact-download.test.ts && tsx src/ui/card-types.test.ts && tsx src/ui/patch-display.test.ts && tsx src/ui/tool-display.test.ts && tsx src/apply-patch.test.ts && tsx src/process-platform.test.ts && tsx src/process-sessions-ci.test.ts && tsx src/codex-goal-sessions-ci.test.ts && tsx src/local-agent-process-tree.test.ts && tsx src/mcp-sessions.test.ts && tsx src/cutover-state.test.ts && tsx src/cutover-activation.test.ts && tsx src/cutover-state-recovery-guard.test.ts && tsx src/cutover-build-ready.test.ts && tsx src/cutover-orchestration.test.ts && tsx src/mcp-cutover.test.ts && tsx src/cutover-restart.test.ts && tsx src/cutover-http.test.ts && tsx src/cutover-recovery.test.ts && tsx src/cutover-binding-repair.test.ts && tsx src/capability-manifest.test.ts && tsx src/server-shutdown.test.ts && tsx src/codex-runtime.test.ts && tsx src/local-agent-config.test.ts && tsx src/local-agent-catalog.test.ts && tsx src/local-agent-presentation.test.ts && tsx src/local-agent-runtime.test.ts && tsx src/local-agent-daemon-lifecycle.test.ts && tsx src/local-agent-daemon-protocol.test.ts && tsx src/local-agent-daemon.test.ts && tsx src/local-agent-codex.test.ts && tsx src/local-agent-opencode.test.ts && tsx src/local-agent-opencode-catalog.test.ts && tsx src/local-agent-acp.test.ts && tsx src/local-agent-grok.test.ts && tsx src/local-agent-pi-sandbox.test.ts && tsx src/local-agent-pi.test.ts && tsx src/local-agent-claude.test.ts && tsx src/local-agent-adapters.test.ts && tsx src/local-agent-availability.test.ts && tsx src/herdr-socket-path.test.ts && tsx src/local-agent-profiles.test.ts && tsx src/local-agent-profile-source.test.ts && tsx src/local-agent-targets.test.ts && tsx src/local-agent-toolchains.test.ts && tsx src/local-agent-idle-policy.test.ts && tsx src/local-agent-capacity.test.ts && tsx src/local-agent-execution-contract.test.ts && tsx src/local-agent-continuation.test.ts && tsx src/provider-scratch.test.ts && tsx src/git-integration-ci.test.ts && tsx src/repository-intelligence.test.ts && tsx src/local-agent-store.test.ts && tsx src/local-agent-manager.test.ts && tsx src/roots.test.ts && tsx src/skills.test.ts && tsx src/workspaces.test.ts && tsx src/workspace-conversation.test.ts && tsx src/conversation-isolation.test.ts && tsx src/review-checkpoints.test.ts && tsx src/server-ci.test.ts && tsx src/oauth-store.test.ts && tsx src/cli-ci.test.ts && tsx src/oauth-json-and-child-reap.test.ts && tsx src/local-agent-errors.test.ts && tsx src/provider-output-redaction.test.ts && tsx src/host-activation.test.ts && tsx src/host-operation-policy.test.ts && tsx src/host-operations.test.ts && tsx src/host-operations-http.test.ts && tsx src/host-operation-external.test.ts && node --import tsx --test src/issue-413-wave1.test.ts && node --import tsx --test src/work-resume-integration.test.ts && tsx src/batch-autonomy-grant.test.ts && node --import tsx --test src/db/migrations.test.ts && node --import tsx --test src/host-capability-snapshot.test.ts && node --import tsx --test src/pi-tools.test.ts && node --import tsx --test src/work-resume.test.ts",
     "verify:nexus-core": "node scripts/nexus-core-verify.mjs",
     "typecheck": "tsc -p tsconfig.json --noEmit",
     "test:carrier-binding": "tsx src/carrier-binding.test.ts",
diff --git a/src/tool-projection-recovery.test.ts b/src/tool-projection-recovery.test.ts
new file mode 100644
index 000000000..4f74a583b
--- /dev/null
+++ b/src/tool-projection-recovery.test.ts
@@ -0,0 +1,106 @@
+// Issue #401: open_workspace(mode=worktree) emits GIT_BASE_REF_NOT_LOCAL and tells the
+// caller to use git_fetch_ref. That tool must be callable on every tool surface that can
+// emit the message. src/server.test.ts holds the same contract but is excluded from
+// `npm test` (DS-1-F6), so this file runs it in CI without codex CLI or OAuth secrets.
+import assert from "node:assert/strict";
+import { readFileSync } from "node:fs";
+import { mkdir, mkdtemp, rm, writeFile } from "node:fs/promises";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import test from "node:test";
+import { Client } from "@modelcontextprotocol/sdk/client/index.js";
+import { InMemoryTransport } from "@modelcontextprotocol/sdk/inMemory.js";
+import { loadConfig, type ServerConfig, type ToolMode } from "./config.js";
+import { DurableOperationManager } from "./durable-operations.js";
+import { ProcessSessionManager } from "./process-sessions.js";
+import { createReviewCheckpointManager } from "./review-checkpoints.js";
+import { createMcpServer } from "./server.js";
+import { SqliteWorkspaceStore } from "./workspace-store.js";
+import { WorkspaceRegistry } from "./workspaces.js";
+
+// Record<ToolMode, ...> makes the compiler reject this table if a ToolMode is added or removed.
+const ALL_TOOL_MODES: Record<ToolMode, true> = { minimal: true, full: true, codex: true, dispatch: true };
+
+async function projectSurface(toolMode: ToolMode): Promise<{ names: string[]; instructions: string }> {
+  const root = await mkdtemp(join(tmpdir(), "devspace-projection-recovery-"));
+  const agentDir = join(root, "agent");
+  const stateDir = join(root, ".state");
+  await mkdir(join(root, "project"), { recursive: true });
+  await mkdir(agentDir, { recursive: true });
+  await writeFile(join(agentDir, "AGENTS.md"), "global instructions\n");
+  const loaded = loadConfig({
+    DEVSPACE_CONFIG_DIR: join(root, ".config"),
+    DEVSPACE_ALLOWED_ROOTS: root,
+    DEVSPACE_WORKTREE_ROOT: join(root, ".worktrees"),
+    DEVSPACE_AGENT_DIR: agentDir,
+    DEVSPACE_WIDGETS: "full",
+    DEVSPACE_TOOL_MODE: toolMode,
+    DEVSPACE_OAUTH_OWNER_TOKEN: "test-owner-token-that-is-long-enough",
+    PORT: "1",
+    DEVSPACE_STATE_DIR: stateDir,
+    DEVSPACE_GIT_CANDIDATES: "false",
+    DEVSPACE_CHAT_SWARM: "0",
+  });
+  const config: ServerConfig = {
+    ...loaded,
+    toolMode,
+    subagents: { ...loaded.subagents, enabled: false },
+  };
+  const store = new SqliteWorkspaceStore(stateDir);
+  const workspaces = new WorkspaceRegistry(config, store);
+  const durableOperations = new DurableOperationManager(config);
+  const processSessions = new ProcessSessionManager();
+  const server = createMcpServer(
+    config,
+    workspaces,
+    createReviewCheckpointManager(),
+    processSessions,
+    () => [],
+    [],
+    undefined,
+    undefined,
+    undefined,
+    durableOperations,
+  );
+  const [clientTransport, serverTransport] = InMemoryTransport.createLinkedPair();
+  const client = new Client({ name: "devspace-projection-recovery-client", version: "1.0.0" });
+  try {
+    await Promise.all([client.connect(clientTransport), server.connect(serverTransport)]);
+    const names = (await client.listTools()).tools.map((tool) => tool.name);
+    return { names, instructions: client.getInstructions() ?? "" };
+  } finally {
+    await client.close();
+    await server.close();
+    durableOperations.close();
+    processSessions.shutdown();
+    store.close();
+    await rm(root, { recursive: true, force: true });
+  }
+}
+
+test("GIT_BASE_REF_NOT_LOCAL error text names the git_fetch_ref recovery tool", () => {
+  const source = readFileSync(new URL("./git-worktrees.ts", import.meta.url), "utf8");
+  const match = source.match(/"GIT_BASE_REF_NOT_LOCAL",\s*"\[GIT_BASE_REF_NOT_LOCAL\][^;]*?\);/);
+  assert.ok(match, "GIT_BASE_REF_NOT_LOCAL throw site not found in src/git-worktrees.ts");
+  assert.match(match[0], /git_fetch_ref/);
+});
+
+for (const toolMode of Object.keys(ALL_TOOL_MODES) as ToolMode[]) {
+  test(`git_fetch_ref recovery is projected in ${toolMode} tool mode`, async () => {
+    const { names, instructions } = await projectSurface(toolMode);
+    const canOpenWorkspace = names.includes("open_workspace");
+    if (canOpenWorkspace) {
+      assert.ok(
+        names.includes("git_fetch_ref"),
+        `${toolMode} lists open_workspace (can emit GIT_BASE_REF_NOT_LOCAL) but not git_fetch_ref`,
+      );
+    }
+    if (instructions.includes("GIT_BASE_REF_NOT_LOCAL")) {
+      assert.match(instructions, /git_fetch_ref/);
+      assert.ok(names.includes("git_fetch_ref"), `${toolMode} instructions cite git_fetch_ref but it is not callable`);
+    }
+    // Every current mode exposes open_workspace and the recovery text; guard against a vacuous pass.
+    assert.ok(canOpenWorkspace, `${toolMode} no longer lists open_workspace; update this contract deliberately`);
+    assert.match(instructions, /GIT_BASE_REF_NOT_LOCAL/);
+  });
+}