# SCOPE

> This file helps you quickly understand what this repository is about,
> when it is relevant, and when it is not.
> It is intentionally lightweight and may be incomplete.

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## One-liner

SSH reverse tunnel lifecycle manager — keeps remote execution environments continuously connected to the local Custodian State Hub via auto-reconnecting port-forwards.

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## Core Idea

Claude Code sessions run locally; the Custodian State Hub API runs locally. Remote machines (Railiance nodes, Temporal workers, Markitect services) need to reach the hub. Ops-bridge manages named SSH reverse tunnels with auto-reconnect, health checks, audit logging, and an MCP server so Claude Code can start/stop/inspect tunnels as tools.

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## In Scope

- Named SSH reverse tunnel lifecycle (`bridge up/down/restart/status/logs`)
- Auto-reconnect with exponential backoff and configurable retry policy
- Optional HTTP health checks (confirm forwarded service is actually reachable from remote)
- Structured audit logging: JSON events (connected, disconnected, health_check_failed, etc.)
- Actor attribution: per-tunnel actor class (human / automation) for audit traceability
- PID + state file management in `~/.local/state/bridge/`
- MCP server exposing tunnel lifecycle + OpsCatalog queries as Claude Code tools
- OpsCatalog: optional Git-backed YAML catalog of infrastructure topology (domains/targets/bridges)

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## Out of Scope

- Identity/credential management (uses existing SSH keys)
- Long-running application hosting on remote machines (port-forward only, not deployment)
- VPN or layer-3 connectivity
- Monitoring/alerting beyond JSON audit logs
- Replacing SSH for general interactive access

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## Relevant When

- Remote Temporal workers or Railiance nodes need to reach the local Custodian MCP
- Need audit trail of which actor (human vs. automation) started/stopped tunnels
- Setting up a new machine in the Railiance ecosystem that must phone home to the hub
- Diagnosing connectivity issues between local hub and remote services

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## Not Relevant When

- All work is local (no remote services involved)
- Manually running `ssh -R` is acceptable
- No need for audit tracing of tunnel state changes

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## Current State

- Status: experimental → active (v0.1 core complete; OpsCatalog planned but not yet shipped)
- Implementation: ~75% — CLI tunneling fully functional, MCP integration working, health checks and audit logging complete; OpsCatalog framework present but not populated
- Stability: stable tunnel lifecycle; tested under network drops and SSH failures
- Usage: running in lab for daily Railiance/Temporal connectivity

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## How It Fits

- Upstream dependencies: SSH (system), OpenSSH server on remote hosts
- Downstream consumers: all remote Claude Code agents depend on ops-bridge to reach local hub MCP; activity-core Temporal server reachable via bridge tunnel
- Often used with: the-custodian (health checks point to hub API), activity-core (Temporal port-forwarding)

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## Terminology

- Preferred terms: tunnel, bridge, actor, actor_class, reconnect policy, health check
- Also known as: "the bridge"
- Potentially confusing terms: "bridge state" is a tunnel-specific state machine (stopped → starting → connected ↔ degraded → reconnecting), not a network bridge

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## Related / Overlapping Repositories

- `the-custodian` — primary consumer; ops-bridge keeps remote agents connected to it
- `activity-core` — Temporal server on remote reached via ops-bridge tunnel
- `railiance-cluster` / `railiance-infra` — remote hosts that need to phone home

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## Provided Capabilities

```capability
type: infrastructure
title: SSH reverse tunnel connectivity
description: Named, auto-reconnecting SSH reverse tunnels with health checks and audit logging — keeps remote execution environments continuously connected to the local Custodian State Hub.
keywords: [ssh, tunnel, reverse-tunnel, connectivity, remote, bridge, ops-bridge]
```

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## Getting Oriented

- Start with: `README.txt` (architecture, config format, CLI commands, MCP integration)
- Key files / directories: `~/.config/bridge/tunnels.yaml` (tunnel config), `~/.local/state/bridge/` (PID/state files)
- Entry points: `bridge --help`; `bridge up <tunnel-name>`; MCP: `bridge_status()`