Add LLM logging and prompt experiment harness

README.md

@@ -29,6 +29,32 @@ A real-time, low-latency audio transcription and translation tool utilizing Open
 
 Run the script using `python3 transcribe.py` with optional flags.
 
+### LLM Prompt Testing
+You can now send the line-correction or paragraph-refinement prompts directly without starting live transcription. Every LLM request is appended as JSON Lines to `logs/llm_requests.jsonl` by default.
+
+- **Test the line-correction prompt:**
+  ```bash
+  python3 main_v2.py --post-correct-model qwen3.5:0.8b --llm-test-line "so um we should probably ship it tomorrow" --llm-test-prev1 "We finished the staging deploy." --llm-test-prev2 "QA signed off this morning."
+  ```
+- **Test the paragraph-refinement prompt:**
+  ```bash
+  python3 main_v2.py --post-correct-model qwen3.5:0.8b --llm-test-context "We reviewed the launch checklist." --llm-test-segments "we confirmed monitoring we confirmed rollback and then talked about the release window"
+  ```
+- **Change where requests are logged:**
+  ```bash
+  python3 main_v2.py --llm-request-log-path tmp/my_llm_requests.jsonl --llm-test-line "example text"
+  ```
+- **Replay the most recent logged request:**
+  ```bash
+  python3 main_v2.py --llm-test-from-log -1
+  ```
+- **Replay a logged request using the original model from the log entry:**
+  ```bash
+  python3 main_v2.py --llm-test-from-log 12 --llm-test-use-logged-model
+  ```
+
+Each log entry includes the timestamp, provider, model, mode, temperature, and full `messages` payload that was sent to the LLM.
+
 ### Common Commands
 - **List available audio devices:**
   ```bash