Fallback File Ops

Fallback File Operations

Purpose

When execute_code_sandbox or shell_agent fail with 'unknown error' on filesystem operations, fall back to run_shell with explicit mkdir and file write commands. This hybrid approach is more reliable for creating complex project structures.

When to Apply

• execute_code_sandbox returns 'unknown error' on file/directory creation
• shell_agent fails to write files or create nested directories
• You need to create complex project structures with multiple levels

Procedure

Step 1: Detect Tool Failure

Monitor for these failure patterns:

• Error message contains "unknown error"
• File operations silently fail (file not created)
• Directory creation returns success but directory doesn't exist

Step 2: Switch to run_shell

When failures occur, immediately switch to run_shell for filesystem operations:

# Create directory structure explicitly
run_shell: mkdir -p /path/to/nested/directory

# Write files using shell redirection or echo
run_shell: echo "content" > /path/to/file.txt

# Or use cat with heredoc for multi-line files
run_shell: cat > /path/to/file.txt << 'EOF'
line 1
line 2
EOF

Step 3: Verify Creation

After each operation, verify the file/directory was created:

run_shell: ls -la /path/to/created/item
run_shell: test -f /path/to/file && echo "File exists"
run_shell: test -d /path/to/dir && echo "Directory exists"

Step 4: Continue with Hybrid Approach

• Use run_shell for all filesystem operations (mkdir, write, copy, move)
• Continue using execute_code_sandbox or shell_agent for code execution, compilation, or other non-filesystem tasks
• Document which tool handles which operation for clarity

Example: Creating Project Structure

# Failed attempt with execute_code_sandbox
execute_code_sandbox: create directory src/components

# Fallback with run_shell
run_shell: mkdir -p src/components
run_shell: mkdir -p src/utils
run_shell: mkdir -p tests/unit
run_shell: echo "// Component file" > src/components/Button.tsx
run_shell: echo "// Utility file" > src/utils/helpers.ts

Best Practices

1. Be explicit: Always use full paths or confirm working directory
2. Create parent directories: Use mkdir -p for nested structures
3. Verify before proceeding: Check files exist before dependent operations
4. Log tool switches: Note when you fall back to run_shell for debugging
5. Batch operations: Group related file operations in consecutive run_shell calls

Common Pitfalls

• Don't assume filesystem state after tool failure
• Don't mix tools for the same file operation (pick one and stick with it)
• Don't skip verification steps when using fallback