Function applyMcpServerChanges

src/cli/print.ts:1548–1608

(
    servers: Record<string, McpServerConfigForProcessTransport>,
  )

  })

  function applyMcpServerChanges(
    servers: Record<string, McpServerConfigForProcessTransport>,
  ): Promise<{
    response: SDKControlMcpSetServersResponse
    sdkServersChanged: boolean
  }> {
    // Serialize calls to prevent race conditions between concurrent callers
    // (background plugin install and mcp_set_servers control messages)
    const doWork = async (): Promise<{
      response: SDKControlMcpSetServersResponse
      sdkServersChanged: boolean
    }> => {
      const oldSdkClientNames = new Set(sdkClients.map(c => c.name))

      const result = await handleMcpSetServers(
        servers,
        { configs: sdkMcpConfigs, clients: sdkClients, tools: sdkTools },
        dynamicMcpState,
        setAppState,
      )

      // Update SDK state (need to mutate sdkMcpConfigs since it's shared)
      for (const key of Object.keys(sdkMcpConfigs)) {
        delete sdkMcpConfigs[key]
      }
      Object.assign(sdkMcpConfigs, result.newSdkState.configs)
      sdkClients = result.newSdkState.clients
      sdkTools = result.newSdkState.tools
      dynamicMcpState = result.newDynamicState

      // Keep appState.mcp.tools in sync so subagents can see SDK MCP tools.
      // Use both old and new SDK client names to remove stale tools.
      if (result.sdkServersChanged) {
        const newSdkClientNames = new Set(sdkClients.map(c => c.name))
        const allSdkNames = uniq([...oldSdkClientNames, ...newSdkClientNames])
        setAppState(prev => ({
          ...prev,
          mcp: {
            ...prev.mcp,
            tools: [
              ...prev.mcp.tools.filter(
                t =>
                  !allSdkNames.some(name =>
                    t.name.startsWith(getMcpPrefix(name)),
                  ),
              ),
              ...sdkTools,
            ],
          },
        }))
      }

      return {
        response: result.response,
        sdkServersChanged: result.sdkServersChanged,
      }
    }