@flowrail/hook

FlowRail's hook dispatcher for Claude Code. It intercepts every Write/Edit/MultiEdit and Bash call your coding agent makes and routes it through FlowRail's security verification pipeline before the change lands.

Sub-commands:

• flowrail-hook pre-write — reconstructs the post-edit file content (plain Write, Edit with replace_all: false / true, and MultiEdit composition), runs a local secret scan and lockfile diff, and verifies code files against your active design review's guardrails via the FlowRail server's flowrail_verify_code MCP tool.
• flowrail-hook pre-bash — inspects tool_input.command, resolves the dependency tree with npm install --dry-run on package-install patterns, and runs FlowRail's 4-signal supply-chain check via the flowrail_check_dep_install MCP tool.
• flowrail-hook stop / session-start — turn-batched whole-app composition review (the cross-file authN/authZ pass no per-file verify can see) and its session-start coverage catch-up.
• flowrail-hook capabilities — prints {name, version, subcommands} for version-skew checks.

Configuration

• FLOWRAIL_MCP_URL — FlowRail server base URL (default http://localhost:8787; the hosted service is https://api.flowrail.ai).
• FLOWRAIL_API_KEY — your API key. Sign up and mint one at flowrail.ai/settings/keys.

The installer (@flowrail/init) bakes the server URL into the hook command line in .claude/settings.json (tracked, no credential), but it never writes your API key to a tracked file — the key lives only in your shell environment. The hook inherits FLOWRAIL_API_KEY from whatever shell launched Claude Code, so keep it exported (e.g. via ~/.zshrc) so every session picks it up.

Install

You normally don't install or invoke this package directly — the one-shot installer wires everything up:

npx @flowrail/init@latest

Links

• Website: https://flowrail.ai
• Docs: https://flowrail.ai/docs