Heliograph MCP server

heliograph

Remote, captured, auditable execution on a machine you cannot log into

A free, open-source tool by DBHQ

Someone can reach the machine. You cannot, and you are the one who knows what to ask it. heliograph runs that gap as a loop rather than a relay: you publish a step, it runs on the far side, and the whole run comes back as a log with every line timestamped in UTC, whether it passed or failed.

you        heliograph send net-probe ────────────────▶ transport
station    picks it up within seconds, runs it
           pushes status, then the log ──────────────▶ transport
you        heliograph logs --last --gaps ◀────────────

The three ways across

heliograph carries a request to a machine you cannot log into, and brings the log back. There are three ways across the gap, and they differ in one thing: what stays held, and for how long.

Beacon. You cannot reach the machine and it cannot reach you - but you can both reach one agreed place. You leave the request there and walk away. Later the machine passes by, picks it up, runs it, and leaves the log for you to collect. Nobody is ever connected; a message waits in the middle. It is the safest of the three, because the code being run is already on the far side and can be read before anything happens - and the slowest, because you wait for the next visit.

Flare. You can reach the machine's door directly. You knock, hand over the request, wait on the step while it runs, and take the log away in the same visit. Nothing waits in the middle and no line stays open. Faster, because there is no pickup to wait for. The trade: you bring the code with you, so the machine trusts the door rather than vetting the code in advance.

Beam. You and the machine bring up a connection and hold it open. Either side can speak at any moment and the other hears it at once, until you hang up. A real session, not a message or a knock - and the most exposed, because while the line is open anything can travel down it. You turn it on deliberately and close it when you are done. It is designed, and not yet a transport you can pick.

In one line: a beacon holds a message, a flare is a single exchange, a beam holds the connection itself.

Does this sound familiar

• You have no SSH access to production, and you are not going to be given any.
• The environment is air-gapped, or behind a bastion, a jump host or a VPN you are not on.
• It is a client-owned or customer-managed estate. Only their staff can log in.
• Access is blocked by policy, not capability: restricted, change-controlled, somebody else's sign-off.
• You are on the fourth round of "can you run this and paste the output", and what came back was a screenshot of half a terminal.
• You are an AI coding agent driving an investigation, and you need the evidence rather than somebody's summary of it.

If you can just SSH in, you do not need this.

Three roles, one boundary

The boundary is the gap, and the layout states it once:

Shortened. The full README is on GitHub.