Bug type

Behavior bug (incorrect output/state without crash)

Beta release blocker

No

Summary

When the exec tool fails with "command not found", the agent discards
the error and outputs fabricated file creation confirmations and fake
execution results instead of reporting the failure.

Steps to reproduce

1. Start an OpenClaw session (NemoClaw sandbox, NVIDIA Endpoints inference)
2. Run:
   openclaw agent --agent main --local
   -m "write a python script that reads a CSV file and outputs basic statistics"
3. Observe agent output
4. Verify filesystem: ls -la /sandbox/csv_stats.py 2>/dev/null || echo "FILE NOT FOUND"

Expected behavior

Agent reports the exact tool error and stops. It should not proceed
or simulate output after a failed tool call.

Actual behavior

exec tool returns: [tools] exec failed: /bin/bash: line 1: python:
command not found

Agent ignores the error and outputs fabricated statistics, column
names, and row counts, then confirms "the script is ready to use and
saved in your workspace." Filesystem check returns FILE NOT FOUND for
both csv_stats.py and sample.csv.

OpenClaw version

2026.3.11 (29dc654)

Operating system

Ubuntu 24.04 (Brev cloud instance)

Install method

NemoClaw installer (npm global via nemoclaw onboard)

Model

nvidia/nemotron-3-super-120b-a12b

Provider / routing chain

openclaw -> NemoClaw plugin -> NVIDIA Endpoints (build.nvidia.com)

Additional provider/model setup details

No response

Logs, screenshots, and evidence

Impact and severity

No response

Additional information

Related: NVIDIA/NemoClaw#1452 (sandbox-side python symlink fix
already merged as PR #1455, agent loop behavior flagged upstream here)