Bug type

Regression (worked before, now fails)

Summary

OpenClaw version
First observed on: 2026.3.11
Not yet retested on: 2026.3.12
Previously worked on 2026.3.8

Environment

• Ubuntu server
• Docker sandbox enabled
• Hardened install layout under /srv/openclaw/...
• Shared sandbox container

Problem
Sandboxed write/edit operations fail when the bot attempts to update files such as MEMORY.md.

Bot/tool error reported

⚠️ ✍️ Write: to MEMORY.md (1755 chars) failed

Exact error returned by tools:

moltbot-sandbox-fs: 2: python3: not found

The same error occurs for both edit and write operations.

Diagnostics

Shared sandbox image:

docker inspect openclaw-sbx-shared --format '{{.Config.Image}}'

Result:
openclaw-sandbox:bookworm-slim

python3 inside sandbox:

docker exec openclaw-sbx-shared sh -lc 'which python3 || echo "python3 missing"'

Result:
python3 missing

Version check:

docker exec openclaw-sbx-shared sh -lc 'python3 --version'

Result:
python3: not found

Check for moltbot-sandbox-fs helper inside container:

docker exec openclaw-sbx-shared sh -lc 'which moltbot-sandbox-fs'

Result:
(no result)

docker exec openclaw-sbx-shared sh -lc 'moltbot-sandbox-fs'

Result:
sh: 1: moltbot-sandbox-fs: not found

Host environment

Host python exists:

/usr/bin/python3

Impact

• read operations work
• edit and write operations fail in sandboxed sessions
• prevents updating files such as MEMORY.md

Workaround

Writing files on the gateway host via exec works.

Example workaround:

exec host=gateway
cat < file
...
EOF

This bypasses the sandbox filesystem bridge.

Expected behavior

Either:

1. sandbox write/edit should work with the default openclaw-sandbox:bookworm-slim image

or

2. the runtime/docs should clearly require a sandbox image that includes python3 when using write/edit tools

Possible cause

The sandbox mutation helper appears to invoke python3 inside the container, but the default slim sandbox image does not contain python3.

Additional notes

The issue appeared immediately after upgrading to 2026.3.11.

Steps to reproduce

Ask bot to update MEMORY.md with latest conversations, etc.
Returns: "⚠️ ✍️ Write: to MEMORY.md (1755 chars) failed" and when asked what the actual error is the bot returns: "moltbot-sandbox-fs: 2: python3: not found (on both edit and write)"

Expected behavior

Expected the MEMORY.md file to be updated

Actual behavior

File not updated

OpenClaw version

2026.3.11

Operating system

Ubuntu 24.04 Server

Install method

npm global

Model

openai 5.3-codex

Provider / routing chain

openclaw -> openai

Config file / key location

No response

Additional provider/model setup details

No response

Logs, screenshots, and evidence

Impact and severity

No response

Additional information

No response