diff --git a/.gitignore b/.gitignore
index 0c81f1c..b8749dd 100644
--- a/.gitignore
+++ b/.gitignore
@@ -32,6 +32,9 @@ env/
 *.swo
 *~
 
+# API Keys
+api_key.txt
+
 # Model files (too large for git)
 *.gguf
 *.safetensors
diff --git a/README.md b/README.md
index 7d53929..e14f6a1 100644
--- a/README.md
+++ b/README.md
@@ -80,10 +80,15 @@ ov1, ov2 = (512, 384) if w >= h else (384, 512)
 Same inputs, outputs, and script rules as `MultiOutputScript`, plus a `jev` namespace that asks [Jev](https://typesafe.ai) (TypeSafe AI's decision model) typed questions about text.
 
 Setup:
-```bash
-pip install typesafe-sdk
-export TYPESAFE_API_KEY="your-api-key"
-```
+1. Install the SDK in the Python environment that runs ComfyUI:
+   ```bash
+   pip install typesafe-sdk
+   ```
+2. Create `api_key.txt` in the actual installation directory of this custom node and add your TypeSafe API key (single line, no quotes):
+   ```
+   ComfyUI/custom_nodes/<your-installation-folder>/api_key.txt
+   ```
+   The key is read from this file on every run; the `TYPESAFE_API_KEY` environment variable is not used. `api_key.txt` is listed in `.gitignore`; never commit it.
 
 Extra input:
 - `max_jev_calls` (INT, default 8): maximum Jev API requests per run. Identical questions within a run are asked only once.
diff --git a/__init__.py b/__init__.py
index 9a46fc6..6dd5ffa 100644
--- a/__init__.py
+++ b/__init__.py
@@ -14,6 +14,7 @@ import ast
 import datetime
 import math
 import random
+from pathlib import Path
 from typing import Any, Dict
 
 from .jev_backend import JevBackend, TypeSafeClient
@@ -22,6 +23,7 @@ from .jev_backend import JevBackend, TypeSafeClient
 _DEFAULT_MAX_STEPS = 10000
 _DEFAULT_MAX_CALL_DEPTH = 32
 _MAX_RANGE_SIZE = 10000
+_API_KEY_PATH = Path(__file__).resolve().parent / "api_key.txt"
 
 _BLOCKED_AST_NODES = (
     ast.Import,
@@ -889,7 +891,16 @@ class MultiOutputScriptJev(MultiOutputScript):
     ):
         if TypeSafeClient is None:
             raise RuntimeError("typesafe-sdk is not installed. Run: pip install typesafe-sdk")
-        with TypeSafeClient() as client:
+        if not _API_KEY_PATH.exists():
+            raise EnvironmentError(
+                f"API key file not found: {_API_KEY_PATH}\nPlease create this file with your TypeSafe API key."
+            )
+        api_key = _API_KEY_PATH.read_text(encoding="utf-8").strip()
+        if not api_key:
+            raise EnvironmentError(
+                f'API key is not set in "{_API_KEY_PATH}"\nPlease add your TypeSafe API key to this file.'
+            )
+        with TypeSafeClient(api_key=api_key) as client:
             return _run_script(
                 code,
                 JevBackend(client, max_jev_calls),