Verify task completion by checking filesystem state when execute_code_sandbox or run_shell return misleading unknown errors
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tessl review fix ./benchmarks/gdpval/skills/verify-success-after-unknown-error/SKILL.mdWhen execute_code_sandbox or run_shell return "unknown error" messages, the underlying task may have actually succeeded. This skill provides a systematic approach to verify actual completion before assuming failure and retrying unnecessarily.
Use this pattern when:
execute_code_sandbox returns "unknown error" but your code may have completedrun_shell fails with unclear error messagesAfter receiving an unknown error, immediately verify if expected files were created:
# Example: Verify file creation after execute_code_sandbox
from tools import list_dir, read_file
# List directory to check if files exist
files = list_dir(path="/workspace/output")
print(files)
# Check specific file existence
expected_files = ["report.pdf", "data.xlsx"]
for f in expected_files:
try:
content = read_file(filetype="pdf", file_path=f"/workspace/output/{f}")
print(f"✓ {f} exists and is readable")
except:
print(f"✗ {f} not found or unreadable")Don't just check existence — verify the files have expected content:
# For spreadsheets
file_content = read_file(filetype="xlsx", file_path="/workspace/output/schedule.xlsx")
# Verify expected sheets, columns, or data exist
# For text/json files
file_content = read_file(filetype="txt", file_path="/workspace/output/result.json")
# Parse and validate structure
# For directories
dir_contents = list_dir(path="/workspace/output")
# Verify expected number of files or specific files existIF expected files exist AND content is valid:
→ Task succeeded despite error message
→ Proceed to next step without retry
ELIF files exist but content is incomplete:
→ Partial success, may need targeted fix
ELSE (files missing or corrupted):
→ True failure, retry or debug requireddef execute_with_verification(code, expected_files):
"""Execute code and verify success even if error returned."""
# Attempt execution
result = execute_code_sandbox(code=code)
# Check for unknown/generic errors
if "unknown error" in result.get("output", "").lower() or result.get("error"):
print("Received error, verifying actual outcome...")
# Verify filesystem state
all_present = True
for f in expected_files:
try:
list_dir(path=f"/workspace/{f}") # or appropriate path
print(f"✓ {f} verified")
except:
print(f"✗ {f} missing")
all_present = False
if all_present:
print("Task completed successfully despite error message")
return {"status": "success_verified", "files": expected_files}
else:
print("True failure - files not created")
return {"status": "failed", "error": result.get("error")}
return {"status": "success", "output": result.get("output")}# After run_shell returns error, verify with:
ls -la /workspace/output/
test -f /workspace/output/result.pdf && echo "File exists" || echo "File missing"
file /workspace/output/result.pdf # Verify file type is correctlist_dir — Check directory contentsread_file — Validate file content and accessibilityexecute_code_sandbox — Primary execution tool this pattern supportsrun_shell — Shell execution tool this pattern supportsc5a9c4b
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