1# guard — example zot extension (Go, phase 3)
2
3Demonstrates the **event subscription** and **tool-call interception**
4half of the extension protocol (phase 3).
5
6What it does:
7
8- Subscribes to `session_start`, `turn_start`, `tool_call`, `turn_end`
9  and appends a line to `/tmp/zot-guard-audit.log` for each.
10- Intercepts every `bash` tool call. If the command matches a danger
11  regex (`rm -rf`, `sudo`, `dd of=/`, `mkfs`, the fork bomb, `chmod -R
12  777`), the call is **refused**. The model sees the refusal as the
13  tool error and (typically) proposes something safer or asks for
14  confirmation.
15
16## Build
17
18```bash
19cd examples/extensions/guard
20go build -o guard .
21```
22
23## Install
24
25```bash
26zot ext install .
27```
28
29## Try it
30
31In zot, ask:
32
33> Run `rm -rf /tmp/foo`
34
35The model's `bash` call is intercepted and refused; the model
36explains the refusal in its reply. No file is touched.
37
38> Run `ls /tmp`
39
40Allowed; the audit log records the call.
41
42Tail the audit log:
43
44```bash
45tail -f /tmp/zot-guard-audit.log
46```
47
48## Extending the danger list
49
50Edit `dangerPatterns` in `main.go`. Each entry is a Go regexp; the
51match is case-insensitive. Rebuild and reinstall.
52
53## See also
54
55- `examples/extensions/hello` — slash command (phase 1)
56- `examples/extensions/clock` — slash command in plain Node (phase 1)
57- `examples/extensions/weather` — LLM-callable tool (phase 2)
58- `docs/extensions.md` — full protocol reference