docs: debugging instructions for docker

.dockerignore

@@ -13,4 +13,5 @@
 !environments/**
 !examples/**
 !openfold3/**
-!scripts/**
+!scripts/**
+!examples/**

docs/source/debugging.md

@@ -0,0 +1,85 @@
+# Debugging OpenFold
+
+## Docker
+
+### Prerequisites
+
+- VS Code with the debugpy extension
+- OpenFold docker image with `debugpy` installed
+
+
+```bash
+docker run --rm \
+    --ipc=host \
+    -it openfold-docker:devel \
+    python -c "import debugpy; print(debugpy)"
+...
+<module 'debugpy' from '/opt/conda/envs/openfold3/lib/python3.12/site-packages/debugpy/__init__.py'>
+```
+
+### Step 1: Instrument your code
+
+Put this snippet at the very top of your launch script 
+
+```python
+import debugpy
+debugpy.listen(("0.0.0.0", 5678))
+print("Waiting for debugger to attach...")
+debugpy.wait_for_client()
+```
+
+For example, put this at the very top of `openfold3/run_openfold.py`
+
+
+### Step 2: Create a launch configuration
+
+Create `.vscode/launch.json` to tell VS Code to connect to `localhost:5678` on the docker container.
+
+```json
+{
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "name": "Python: Remote Attach",
+            "type": "debugpy",
+            "request": "attach",
+            "connect": {
+                "host": "localhost",
+                "port": 5678
+            },
+            "pathMappings": [
+                {
+                    "localRoot": "${workspaceFolder:openfold-3}",
+                    "remoteRoot": "/opt/openfold3"
+                }
+            ]
+        }
+    ]
+}
+```
+
+> **Note**: Use `${workspaceFolder}` instead if openfold-3 is your only workspace folder.
+
+### Step 3: Launch your container
+
+Launch the docker container with the debugger port exposed:
+
+```bash
+docker run --rm \
+    --gpus all \
+    --ipc=host \
+    -p 5678:5678 \
+    -it openfold-docker:devel \
+    run_openfold predict \
+        --query_json /data/query.json \
+        --runner_yaml ./examples/example_runner_yamls/low_mem.yml \
+        --output_dir /tmp/output
+```
+
+> **Important**: The `-p 5678:5678` flag is required to expose the debugger port.
+
+The script will print "Waiting for debugger to attach..." and pause until you connect. 
+
+### Step 4: Attach the debugger
+
+In VS Code, open the Run and Debug panel (`Ctrl+Shift+D`) and click the green play button to attach. 

pyproject.toml

@@ -70,6 +70,7 @@ test = [
   "pytest-xdist",
   "pytest-cov",
   "pytest-benchmark",
+  "debugpy",
 ]
 
 [project.optional-dependencies]