Risk alerting - logging only for now. The data's all there (cost, risk, timing per event) so threshold alerts are straightforward to add. I wanted to nail visibility before touching enforcement. It's next.
Ledger tamper resistance - out of scope for v1, intentionally. You're right that a compromised agent with fs access could modify it. The real fix is a hash chain so tampering is detectable after the fact. I didn't want to over-engineer before validating the basic use case, but it's the right next step on the integrity side.
Cursor billing - Cursor stores per-request token usage in a local SQLite db at ~/.cursor-server/data/state.vscdb. That's your data on your machine, vigilo just reads it. The cursor.com billing endpoint wasn't documented but wasn't hard to find by watching network traffic. Worth noting: the cursor-usage command is purely additive — if Cursor changes their schema it degrades gracefully, but the core audit trail (MCP + hooks) has zero dependency on it.
On tool coverage - Claude Code is fully covered via matcher: ".*" on PostToolUse, every built-in tool fires through it. Cursor coverage was partial by default (Bash and Edit only) - pushed a fix today that adds beforeReadFile and beforeMCPExecution to the default setup.