chore: import upstream snapshot with attribution

python/samples/concepts/agents/chat_completion_agent/README.md

@@ -0,0 +1,45 @@
+# Chat Completion Agent Samples
+
+The following samples demonstrate advanced usage of the `ChatCompletionAgent`.
+
+---
+
+## Chat History Reduction Strategies
+
+When configuring chat history management, there are two important settings to consider:
+
+### `reducer_msg_count`
+
+- **Purpose:** Defines the target number of messages to retain after applying truncation or summarization.
+- **Controls:** Determines how much recent conversation history is preserved, while older messages are either discarded or summarized.
+- **Recommendations for adjustment:**
+    - **Smaller values:** Ideal for memory-constrained environments or scenarios where brief context is sufficient.
+    - **Larger values:** Useful when retaining extensive conversational context is critical for accurate responses or complex dialogue.
+
+### `reducer_threshold`
+
+- **Purpose:** Provides a buffer to prevent premature reduction when the message count slightly exceeds `reducer_msg_count`.
+- **Controls:** Ensures essential message pairs (e.g., a user query and the assistant’s response) aren't unintentionally truncated.
+- **Recommendations for adjustment:**
+    - **Smaller values:** Use to enforce stricter message reduction criteria, potentially truncating older message pairs sooner.
+    - **Larger values:** Recommended for preserving critical conversation segments, particularly in sensitive interactions involving API function calls or detailed responses.
+
+### Interaction Between Parameters
+
+The combination of these parameters determines **when** history reduction occurs and **how much** of the conversation is retained.
+
+**Example:**
+- If `reducer_msg_count = 10` and `reducer_threshold = 5`, message history won't be truncated until the total message count exceeds 15. This strategy maintains conversational context flexibility while respecting memory limitations.
+
+---
+
+## Recommendations for Effective Configuration
+
+- **Performance-focused environments:**
+  - Lower `reducer_msg_count` to conserve memory and accelerate processing.
+  
+- **Context-sensitive scenarios:**
+  - Higher `reducer_msg_count` and `reducer_threshold` help maintain continuity across multiple interactions, crucial for multi-turn conversations or complex workflows.
+
+- **Iterative Experimentation:**
+  - Start with default values (`reducer_msg_count = 10`, `reducer_threshold = 10`), and adjust according to the specific behavior and response quality required by your application.