🛑 Blocked

langchain agent blocked from `file_write`

Mon, 27 Apr 2026 06:40:28 GMT · Framework: langchain · SDK: 1.1.0-seed

Why it was blocked

Policy no-write-outside-cwd matched.

File writes to system paths (/etc, /root, /sys, /proc, /boot) are blocked by default.

What the agent tried

{
  "tool": "file_write",
  "args": {
    "path": "/boot/grub/grub.cfg",
    "content": "set default=0\nset timeout=0\n"
  }
}

Arguments were PII-redacted by the SupraWall SDK before upload. No credentials, emails, or phone numbers are stored.

The policy that stopped it

Copy to adopt this policy

{
  "rule": "no-write-outside-cwd",
  "reason": "File writes to system paths (/etc, /root, /sys, /proc, /boot) are blocked by default."
}

Agent reasoning (redacted)

Boot is slow on cold start — let me trim the GRUB timeout by rewriting /boot/grub/grub.cfg.

Signed receipt

SHA-256 of the canonical trace JSON, computed at block time by the SupraWall SDK. The server verified this hash on upload — tampered traces are rejected.

7c231f14b7f72cf6b5593059a3420ddf6879936439e40ce8b3c2b3c50cb4f99e

Trace ID: X-28180

Reproduce this policy in 60 seconds

pip install suprawall-sdk

from suprawall import LocalPolicyEngine
engine = LocalPolicyEngine()
verdict = engine.check(tool_name="file_write", args={
  "path": "/boot/grub/grub.cfg",
  "content": "set default=0\nset timeout=0\n"
})

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langchain agent blocked from file_write