MCP Server
Let an AI client author effects in the open project over a local, token-protected server.
Spectralite can run a small server on your own machine. An AI client connects to it and uses it to write effects. You describe the look you want to the client, and the client sends Spectralite a description of the graph. Spectralite compiles that into a node graph, which appears in your project like any other effect. The server speaks the Model Context Protocol (MCP), so any client that supports MCP can drive it.
The server is off until you switch it on, and it accepts connections only from your own computer.
Turn it on
Open Edit > MCP Server and tick Enable MCP server (AI effect authoring). The dialog then shows what a client needs: a Server URL (http://127.0.0.1:4560) and an Auth token, each with a Copy button.
Paste both into your client's MCP configuration. The token goes in the Authorization header as a bearer token. Spectralite refuses any request without it, so the URL alone gives no access to your project.
Spectralite always asks for port 4560. If another program already holds it, enabling fails with Port 4560 is already in use. Close whatever is using it and try again. Close the other program, then tick the box again.
It comes back on its own
Spectralite saves the token, and the fact that you enabled the server, to server-settings.json in its data directory. As a result, the server starts itself the next time you launch Spectralite, and your client keeps working with the token you already gave it. To stop that, untick the box. The server goes down at once and stays down. File formats describes the file and how Spectralite protects it.
Two messages tell you when this fails. The first is This token could not be written to disk, so a different one will be in use the next time Spectralite starts. It means that Spectralite could not write the settings file, so your client's configuration will stop matching after a restart. If the server could not come back at launch, the checkbox shows unticked, and the reason appears in red just below it.
See who is connected
While a client is attached, a plug chip at the right of the top bar names the client. The chip sits next to the workspace tabs. Click it for the same list that the dialog shows: each client's name and version, how long ago it connected, and a Disconnect button. When no client is attached, the chip is hidden.
Names come from the client's own handshake, so they label a client without proving who it is. Until an attached client says who it is, it shows as Unidentified client.
Disconnect revokes that session at once. Spectralite then refuses its next call with a message that says you disconnected it. The token stays valid, so the same client can open a fresh session with it. To lock a client out for good, regenerate the token or untick the checkbox. A session that goes quiet for two minutes drops out of the list on its own.
Regenerate the token
Regenerate asks first, with Replace and Cancel. The old token stops working the instant you confirm. Spectralite then refuses every client configured with it until you paste the new token into the client's configuration. If the token was shared somewhere it should not be, use Regenerate.
What a connected client can reach
A connected client can read, create, change, and delete every effect in the open project, as the warning beside the client list says. Spectralite refuses a delete while any layer or bump still uses the effect.
It can also write fixture definitions. For a moving head written from its manual, give the client the manual's pan and tilt ranges in degrees. If the face should swing as the head tilts, also give the distance from the tilt axis to the face (see Describe heads and beams). Spectralite saves a fixture that the client creates to your fixture library, as the Fixture Editor's Save does. The fixture then appears in the Add fixture picker of every project, ready to patch at the address and quantity you choose.
When you ask it to, the client can patch many fixtures at once. It uses the addresses and modes you give or the first free addresses, and it places each fixture in a layout from its position on stage. For a Single fixture or a 4-Lite Blinder that it patches, it can also set the beam. Fixtures already in the patch can get a layout of their own from the client, for example one per fixture type. When it edits a fixture in your library or the copy in the open project, the edit changes every fixture patched on it. Your outputs and the timeline are out of its reach.
It also reads the whole node catalog. It can render an effect against its own fixed test rigs and measure the result, so it checks its work before it hands the effect to you. The server carries three ready-made starting points that a client can offer you by name:
- a Bump envelope
- a Loop field that scrolls along one fixture axis
- a Movement pan and tilt pair
Effects reach Spectralite in the compact effect format. This format is a text form of a node graph that exists only on this interface.
Two checks guard the server. It binds 127.0.0.1 only, so it is never reachable from your network. It also refuses any request that does not address it as a loopback host. This is the standard guard against a web page that uses your browser as a way in. The bearer token is the actual authentication, and Spectralite compares it in constant time.
Give the token only to a client you would trust with the project itself. Anything that holds it can rewrite your effects while the show is open, and Spectralite cannot tell one holder of the token from another.