Code Execution Fallback & Workspace Anchoring
This skill provides a robust pattern for executing code when the primary method fails, combined with proper workspace path management to prevent file location errors.
Core Techniques
1. Workspace Path Anchoring
Always establish and verify your working directory at the start of any task:
python# At the beginning of any code execution import os workspace_path = os.getcwd() print(f"Working directory: {workspace_path}")
bash# In shell scripts pwd echo "Current directory: $(pwd)"
Why: Prevents files from being written to unexpected locations when agents switch between tools.
2. Execution Fallback Ladder
When execute_code_sandbox fails, follow this escalation pattern:
Level 1: Retry with Simpler Code
- Simplify the code structure
- Remove complex dependencies
- Add explicit error handling
Level 2: Use run_shell with Heredoc
When sandbox execution repeatedly fails, switch to shell execution:
bashpython3 << 'EOF' import os import pandas as pd # Your code here data = {"col1": [1, 2, 3], "col2": ["a", "b", "c"]} df = pd.DataFrame(data) df.to_csv("output.csv", index=False) print("File written successfully") EOF
Key points:
- Use
<< 'EOF'(quoted) to prevent variable expansion - Include all imports and dependencies inline
- Add explicit success/failure messages
Level 3: Delegate to shell_agent
For complex multi-step tasks with error recovery needs:
Task: Create a data processing pipeline that reads CSV, transforms data, and outputs Excel Requirements: - Handle missing values - Apply transformations - Write to ./output/ directory - Retry on transient errors
3. Explicit Path Management
Always use absolute or explicitly relative paths:
python# BAD - relies on implicit working directory df.to_csv("output/data.csv") # GOOD - explicit path anchoring import os base_path = os.getcwd() output_dir = os.path.join(base_path, "output") os.makedirs(output_dir, exist_ok=True) df.to_csv(os.path.join(output_dir, "data.csv"))
bash# BAD cd some_dir && python script.py # GOOD SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)" cd "$SCRIPT_DIR" python script.py
Decision Tree
execute_code_sandbox fails? ├── Yes, with syntax/import errors → Fix code, retry Level 1 ├── Yes, with timeout/resource errors → Use Level 2 (run_shell heredoc) ├── Yes, with unknown/unclear errors → Use Level 3 (shell_agent) └── No, success → Verify output file exists at expected path
Common Failure Scenarios & Solutions
| Error Type | Likely Cause | Recommended Fallback |
|---|---|---|
| ModuleNotFoundError | Missing packages | run_shell with pip install first |
| Timeout | Long-running operation | shell_agent with progress tracking |
| PermissionError | Wrong directory | Verify workspace path, use explicit paths |
| Unknown error | Sandbox limitations | run_shell or shell_agent |
Example: Robust File Generation
python# Step 1: Anchor workspace import os workspace = os.getcwd() print(f"Workspace: {workspace}") # Step 2: Create output directory explicitly output_path = os.path.join(workspace, "deliverables") os.makedirs(output_path, exist_ok=True) # Step 3: Generate content with error handling try: # Your generation logic here with open(os.path.join(output_path, "report.txt"), "w") as f: f.write("Content here") print(f"Success: File written to {output_path}") except Exception as e: print(f"Error: {e}") # Signal to escalate to run_shell or shell_agent raise
Anti-Patterns to Avoid
- ❌ Assuming current directory without verification
- ❌ Using relative paths like
../output/file.txtwithout context - ❌ Repeatedly retrying failed
execute_code_sandboxwithout changing approach - ❌ Not checking if output files exist after generation
- ❌ Mixing implicit and explicit path styles in same task
Verification Checklist
After any code execution:
- Confirm working directory was verified at start
- Confirm output files exist at expected paths
- Confirm file contents are non-empty and valid
- If execution failed, escalate to next fallback level within 2 retries

