add README.md

README.md

@@ -1,2 +1,60 @@
-# task-699cc158d6d3a5544a3ed35b
+# Stream‑mode LangChain Agent
 
+## What this project does
+
+This repository contains a minimal example that demonstrates how to replace the
+`invoke()` call of a LangChain agent with the streaming interface `stream()`.  The
+output is printed token by token so that the user can see the agent “think” in
+real time.
+
+The script uses the BroJS LLM provider and a tiny mock tool called
+`get_price` to illustrate how tools are called while streaming.
+
+## File structure
+
+```
+├── main.py          # Entry point – shows three example invocations
+├── requirements.txt # Dependencies (no exact versions)
+└── README.md        # This file
+```
+
+## Installation
+
+```bash
+pip install -r requirements.txt
+export JOURNAL_MCP_PAT=YOUR_BROJS_TOKEN  # required for the LLM
+python main.py
+```
+
+## Example output
+
+Running `python main.py` produces something like:
+
+```
+=== Example 1 ===
+--- Step 0 ---
+Paris is the capital of France.
+--- End ---
+
+=== Example 2 ===
+--- Step 0 ---
+The price of milk in Kazan is 89 rubles.
+--- End ---
+
+=== Example 3 ===
+--- Step 0 ---
+The price of bread in Kazan is 45 rubles.
+The price of coffee in Moscow is 120 rubles.
+--- End ---
+```
+
+## How it works
+
+* The agent is created with `create_agent` and a single tool.
+* `agent.stream()` returns an iterator that yields tuples `(chunk_type,
+  chunk_data)` where `chunk_type` can be `'messages'` or `'updates'`.
+* Tokens are printed as they arrive, and step changes are highlighted with
+  a separator line.
+
+Feel free to extend the tool set or modify the prompt – the streaming logic
+remains unchanged.