LSP API

Use this API to register/manage language servers used by Acode's CodeMirror LSP client.

Import

const lsp = acode.require("lsp");

Important Transport Reality

CodeMirror's LSP client in Acode communicates via WebSocket transport.

• transport.kind: "websocket" is the recommended and practical mode.
• transport.kind: "stdio" is not a direct stdio pipe to the editor.
• In this codebase, stdio mode still expects a WebSocket bridge URL.

For local stdio language servers, use an AXS bridge (launcher.bridge) and keep transport as websocket.

WARNING

stdio with only transport.command is not enough in Acode.
You still need a WebSocket bridge endpoint (AXS or equivalent) for the client connection.

Recommended Setup (Local Server via AXS Bridge)

lsp.registerServer(
  {
    id: "typescript-custom",
    label: "TypeScript (Custom)",
    languages: ["javascript", "javascriptreact", "typescript", "typescriptreact", "tsx", "jsx"],
    transport: {
      kind: "websocket",
      // url can be omitted when using launcher.bridge auto-port mode
    },
    launcher: {
      bridge: {
        kind: "axs",
        command: "typescript-language-server",
        args: ["--stdio"],
      },
      checkCommand: "which typescript-language-server",
      install: {
        command:
          "apk add --no-cache nodejs npm && npm install -g typescript-language-server typescript",
      },
    },
    enabled: true,
    initializationOptions: {
      provideFormatter: true,
    },
  },
  { replace: true },
);

Remote/External WebSocket Server

lsp.registerServer({
  id: "remote-lsp",
  label: "Remote LSP",
  languages: ["json"],
  transport: {
    kind: "websocket",
    url: "ws://127.0.0.1:2087/",
    options: {
      binary: true,
      timeout: 5000,
    },
  },
  enabled: true,
});

API Reference

registerServer(definition, options?)

• options.replace?: boolean (default false)
  • false: existing server with same id is kept
  • true: existing server is replaced

Definition fields commonly used:

• id (required): normalized to lowercase
• label (optional)
• languages (required): non-empty array, normalized to lowercase
• enabled (optional, default true)
• transport (required)
  • kind: "websocket" or "stdio" (see transport note above)
  • url?: string
  • command?: string (required by registry validation when using stdio)
  • args?: string[]
  • options?: { binary?, timeout?, reconnect?, maxReconnectAttempts? }
• launcher (optional)
  • startCommand?: string | string[]
  • command?: string
  • args?: string[]
  • checkCommand?: string
  • install?: { command?: string }
  • bridge?: { kind: "axs", command: string, args?: string[], port?: number, session?: string }
• initializationOptions?: object
• clientConfig?: object
• startupTimeout?: number
• capabilityOverrides?: object
• rootUri?: (uri, context) => string | null
• resolveLanguageId?: (context) => string | null
• useWorkspaceFolders?: boolean

Other Registry Methods

• unregisterServer(id)
• updateServer(id, updater)
• getServer(id)
• listServers()
• getServersForLanguage(languageId, options?)

const jsServers = lsp.getServersForLanguage("javascript");

lsp.updateServer("typescript-custom", (current) => ({
  ...current,
  enabled: false,
}));

getServersForLanguage options:

• includeDisabled?: boolean (default false)

Client Manager

• clientManager.setOptions(options)
• clientManager.getActiveClients()

lsp.clientManager.setOptions({
  diagnosticsUiExtension: [],
});

const activeClients = lsp.clientManager.getActiveClients();
console.log(activeClients);