diff --git a/scripts/provision-worktree.sh b/scripts/provision-worktree.sh
index 725f9c67802..a80c01f7793 100644
--- a/scripts/provision-worktree.sh
+++ b/scripts/provision-worktree.sh
@@ -332,11 +332,15 @@ main().catch((error) => {
 EOF
 }
 
-if paperclipai_command_available; then
-  run_isolated_worktree_init
+if [[ -e "$worktree_config_path" && -e "$worktree_env_path" ]]; then
+  echo "Reusing existing isolated Paperclip worktree config at $worktree_config_path" >&2
 else
-  echo "paperclipai CLI not available in this workspace; writing isolated fallback config without DB seeding." >&2
-  write_fallback_worktree_config
+  if paperclipai_command_available; then
+    run_isolated_worktree_init
+  else
+    echo "paperclipai CLI not available in this workspace; writing isolated fallback config without DB seeding." >&2
+    write_fallback_worktree_config
+  fi
 fi
 
 list_base_node_modules_paths() {
diff --git a/server/src/__tests__/workspace-runtime.test.ts b/server/src/__tests__/workspace-runtime.test.ts
index e44f40da957..50e89c017cf 100644
--- a/server/src/__tests__/workspace-runtime.test.ts
+++ b/server/src/__tests__/workspace-runtime.test.ts
@@ -897,7 +897,7 @@ describe("realizeExecutionWorkspace", () => {
     await runGit(repoRoot, ["commit", "-m", "Add worktree provision script"]);
 
     try {
-      const workspace = await realizeExecutionWorkspace({
+      const workspaceInput = {
         base: {
           baseCwd: repoRoot,
           source: "project_primary",
@@ -923,7 +923,8 @@ describe("realizeExecutionWorkspace", () => {
           name: "Codex Coder",
           companyId: "company-1",
         },
-      });
+      } satisfies Parameters<typeof realizeExecutionWorkspace>[0];
+      const workspace = await realizeExecutionWorkspace(workspaceInput);
 
       const configPath = path.join(workspace.cwd, ".paperclip", "config.json");
       const envPath = path.join(workspace.cwd, ".paperclip", ".env");
@@ -954,6 +955,34 @@ describe("realizeExecutionWorkspace", () => {
 
       process.chdir(workspace.cwd);
       expect(resolvePaperclipConfigPath()).toBe(configPath);
+
+      const preservedPort = 39999;
+      await fs.writeFile(
+        configPath,
+        JSON.stringify(
+          {
+            ...configContents,
+            server: {
+              ...configContents.server,
+              port: preservedPort,
+            },
+          },
+          null,
+          2,
+        ) + "\n",
+        "utf8",
+      );
+      await fs.writeFile(envPath, `${envContents}PAPERCLIP_WORKTREE_COLOR="#112233"\n`, "utf8");
+
+      const reusedWorkspace = await realizeExecutionWorkspace(workspaceInput);
+      const reusedConfigContents = JSON.parse(await fs.readFile(configPath, "utf8"));
+      const reusedEnvContents = await fs.readFile(envPath, "utf8");
+
+      expect(reusedWorkspace.cwd).toBe(workspace.cwd);
+      expect(reusedWorkspace.created).toBe(false);
+      expect(reusedConfigContents.server.port).toBe(preservedPort);
+      expect(reusedConfigContents.database.embeddedPostgresDataDir).toBe(path.join(expectedInstanceRoot, "db"));
+      expect(reusedEnvContents).toContain('PAPERCLIP_WORKTREE_COLOR="#112233"');
     } finally {
       process.chdir(previousCwd);
     }