diff --git a/plugins/nemo-safe-synthesizer/src/nemo_safe_synthesizer_plugin/cli.py b/plugins/nemo-safe-synthesizer/src/nemo_safe_synthesizer_plugin/cli.py
index 6211d16ed1..dff9348079 100644
--- a/plugins/nemo-safe-synthesizer/src/nemo_safe_synthesizer_plugin/cli.py
+++ b/plugins/nemo-safe-synthesizer/src/nemo_safe_synthesizer_plugin/cli.py
@@ -5,6 +5,7 @@
 
 from __future__ import annotations
 
+import os
 import subprocess
 from pathlib import Path
 from typing import ClassVar
@@ -14,6 +15,9 @@
 from nemo_safe_synthesizer_plugin.config import config
 from nemo_safe_synthesizer_plugin.runtime import runtime_info, runtime_task_command, setup_runtime
 
+NEMO_DEPLOYMENT_TYPE_ENVVAR = "NEMO_DEPLOYMENT_TYPE"
+NMP_DEPLOYMENT_TYPE = "nmp"
+
 
 class SafeSynthesizerCLI(NemoCLI):
     """CLI extensions for host-local Safe Synthesizer development."""
@@ -100,7 +104,9 @@ def run_local_command(
                 typer.echo(str(e), err=True)
                 raise typer.Exit(1) from e
 
-            result = subprocess.run(command, check=False)
+            runtime_env = os.environ.copy()
+            runtime_env[NEMO_DEPLOYMENT_TYPE_ENVVAR] = NMP_DEPLOYMENT_TYPE
+            result = subprocess.run(command, check=False, env=runtime_env)
             if result.returncode != 0:
                 raise typer.Exit(result.returncode)
             typer.echo(f"Wrote Safe Synthesizer results to {output_dir}")
diff --git a/plugins/nemo-safe-synthesizer/tests/unit/test_cli.py b/plugins/nemo-safe-synthesizer/tests/unit/test_cli.py
new file mode 100644
index 0000000000..1c65b626db
--- /dev/null
+++ b/plugins/nemo-safe-synthesizer/tests/unit/test_cli.py
@@ -0,0 +1,48 @@
+# SPDX-FileCopyrightText: Copyright (c) 2025-2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+from subprocess import CompletedProcess
+
+from nemo_safe_synthesizer_plugin import cli
+from nemo_safe_synthesizer_plugin.cli import NEMO_DEPLOYMENT_TYPE_ENVVAR, NMP_DEPLOYMENT_TYPE, SafeSynthesizerCLI
+from typer.testing import CliRunner
+
+
+def test_run_local_sets_nmp_deployment_type_for_runtime_subprocess(tmp_path, monkeypatch):
+    spec_file = tmp_path / "nss-job.json"
+    spec_file.write_text("{}", encoding="utf-8")
+    data_file = tmp_path / "input.csv"
+    data_file.write_text("name\nAda\n", encoding="utf-8")
+    output_dir = tmp_path / "nss-output"
+    captured = {}
+
+    def fake_runtime_task_command(_config, args):
+        return ["runtime-python", *args]
+
+    def fake_run(command, *, check=False, env=None):
+        captured["command"] = command
+        captured["check"] = check
+        captured["env"] = env
+        return CompletedProcess(command, 0)
+
+    monkeypatch.setattr(cli, "runtime_task_command", fake_runtime_task_command)
+    monkeypatch.setattr(cli.subprocess, "run", fake_run)
+
+    result = CliRunner().invoke(
+        SafeSynthesizerCLI().get_cli(),
+        [
+            "run-local",
+            "--workspace",
+            "default",
+            "--spec-file",
+            str(spec_file),
+            "--data-source",
+            str(data_file),
+            "--output-dir",
+            str(output_dir),
+        ],
+    )
+
+    assert result.exit_code == 0, result.output
+    assert captured["check"] is False
+    assert captured["env"][NEMO_DEPLOYMENT_TYPE_ENVVAR] == NMP_DEPLOYMENT_TYPE