node9 sees every tool call Pi makes, through a node9 extension that runs inside the agent, including the ! shell side channel.
Pi is protected by a node9 extension rather than hooks or MCP.
| Surface | How node9 is wired | What it does |
|---|---|---|
| Every tool call | tool_call in ~/.pi/agent/extensions/node9.js | allow / review / block before the tool runs |
| Prompts | input | prompt secret scan |
The ! / !! shell side channel | user_bash | gated like any other command |
| Every tool result | tool_result | audit record, and output redaction in place |
Set it up
node9 agents add pi
node9 init does this for every agent it detects on the machine. Either command is safe to
re-run; it repairs a hook that an agent update removed and leaves everything else alone.
What is not covered
- MCP servers are not wrapped for Pi.
- Cost is not tracked for Pi.
Verify it on this machine
node9 doctor # is the hook (or MCP wrap) actually in place?
node9 explain Bash 'cat ~/.ssh/id_rsa' # shows the verdict the live hook enforces: BLOCK
node9 explain prints the exact rule that fires and where the decision came from. If doctor
says the agent is not wired, the guard is not running, whatever the config looks like.
Every agent, side by side
node9 wires into twelve agents and the depth differs. The coverage matrix shows all of them in one table, including which ones node9 cannot see the shell of.