AstraZeneca
diff --git a/‎argo-pipeline.yaml‎
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diff --git a/‎docs/architecture/context-isolation.md‎
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+# Context Isolation in Runnable
+
+## Problem Solved
+
+Previously, `run_context` was a global variable that caused issues when multiple pipelines ran concurrently (e.g., in FastAPI endpoints). All pipelines would share the same context, leading to:
+
+- Data leakage between pipelines
+- Incorrect run IDs in logs
+- Configuration mix-ups
+- Resource conflicts
+
+## Solution
+
+Replaced the global variable with Python's `contextvars` module, providing:
+
+- **Request isolation**: Each execution context maintains its own run context
+- **Async safety**: Contexts automatically propagate through async/await chains
+- **Thread safety**: Works correctly with thread pools and concurrent execution
+- **Explicit error handling**: Clear errors when no context is available
+
+## Usage
+
+```python
+from runnable.context import get_run_context, set_run_context
+
+# Get current context (returns None if no context)
+current_context = get_run_context()
+
+# Set context (automatically isolated per request/task)
+set_run_context(my_context)
+
+# Context automatically propagates through async chains
+async def my_async_function():
+    context = get_run_context()  # Same context as caller
+    await some_other_async_function()
+```
+
+## Migration Notes
+
+- The global `context.run_context` variable has been removed
+- New code must use `get_run_context()` to access the context
+- Error handling is now explicit - functions raise `RuntimeError` if no context available
+- No changes needed for FastAPI or async usage - isolation happens automatically
+
+## Implementation Details
+
+The implementation uses Python's `contextvars.ContextVar`:
+
+```python
+_run_context_var: contextvars.ContextVar[Optional[RunnableContextType]] = contextvars.ContextVar(
+    'run_context',
+    default=None
+)
+
+def get_run_context() -> Optional[RunnableContextType]:
+    """Get the current run context for this execution context."""
+    return _run_context_var.get()
+
+def set_run_context(context: RunnableContextType) -> None:
+    """Set the run context for this execution context."""
+    _run_context_var.set(context)
+```
+
+This ensures each async task, thread, or request maintains its own isolated context.