Add interactive streaming CLI example using the Responses API

examples/streaming/interactive_enigma_cli.py

@@ -0,0 +1,89 @@
+from openai import OpenAI
+
+SECRET_PHRASE = "unlock protocol nightwing"
+
+SYSTEM_PROMPT = (
+    "You are an enigmatic but helpful assistant. "
+    "You answer in short, slightly cryptic hints, but always accurate and safe. "
+    f"If the user ever types the exact phrase '{SECRET_PHRASE}', "
+    "you drop the enigmatic tone and explain, step-by-step, how this CLI works, "
+    "how the streaming API is being used, and how a developer could adapt this "
+    "example into their own application."
+)
+
+
+class Conversation:
+    """Keep the conversation history in a format compatible with the OpenAI Responses API."""
+
+    def __init__(self, system_prompt: str) -> None:
+        self.history = [
+            {"role": "system", "content": system_prompt},
+        ]
+
+    def add_user(self, content: str) -> None:
+        self.history.append({"role": "user", "content": content})
+
+    def add_assistant(self, content: str) -> None:
+        self.history.append({"role": "assistant", "content": content})
+
+    def as_input(self):
+        # The Responses API accepts a list of messages as `input`
+        return self.history
+
+
+def stream_response(client: OpenAI, conversation: Conversation) -> str:
+    """Send the conversation history to the model using streaming and return the full response text."""
+    full_text = []
+
+    with client.responses.stream(
+        model="gpt-4.1-mini",
+        input=conversation.as_input(),
+    ) as stream:
+        for event in stream:
+            text_chunk = getattr(event, "delta", None)
+            if not text_chunk:
+                text_chunk = getattr(event, "text", None)
+
+            if text_chunk:
+                print(text_chunk, end="", flush=True)
+                full_text.append(str(text_chunk))
+
+    print()
+    return "".join(full_text)
+
+
+def main() -> None:
+    client = OpenAI()
+    convo = Conversation(SYSTEM_PROMPT)
+
+    print(">>> Enigma interface online.")
+    print(">>> Type your message (or 'quit' to exit).")
+    print(">>> Hint: there is a hidden phrase you can try... ;)\n")
+
+    while True:
+        try:
+            user_input = input("You: ").strip()
+        except (EOFError, KeyboardInterrupt):
+            print("\n>>> Shutting down. See you in the logs.")
+            break
+
+        if user_input.lower() in {"quit", "exit"}:
+            print(">>> Shutting down. See you in the logs.")
+            break
+
+        if user_input == SECRET_PHRASE:
+            user_input = (
+                f"{SECRET_PHRASE} — Explain clearly that this is just an "
+                "interactive streaming demo, describe its architecture, and "
+                "guide a developer on how to reuse this pattern in their own project."
+            )
+
+        convo.add_user(user_input)
+
+        print("Enigma:", end=" ", flush=True)
+        assistant_text = stream_response(client, convo)
+        convo.add_assistant(assistant_text)
+
+
+if __name__ == "__main__":
+    main()