Cloudflare Access MCP Server

apps/cloudflare-one-access/.dev.vars.example

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+CLOUDFLARE_CLIENT_ID=
+CLOUDFLARE_CLIENT_SECRET=
+DEV_DISABLE_OAUTH=
+DEV_CLOUDFLARE_API_TOKEN=
+DEV_CLOUDFLARE_EMAIL=

apps/cloudflare-one-access/package.json

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+{
+	"name": "cloudflare-one-access-mcp-server",
+	"version": "0.0.1",
+	"private": true,
+	"scripts": {
+		"check:lint": "run-eslint-workers",
+		"check:types": "run-tsc",
+		"deploy": "run-wrangler-deploy",
+		"dev": "wrangler dev",
+		"start": "wrangler dev",
+		"types": "wrangler types --include-env=false",
+		"test": "vitest run"
+	},
+	"dependencies": {
+		"@cloudflare/workers-oauth-provider": "0.0.5",
+		"@hono/zod-validator": "0.4.3",
+		"@modelcontextprotocol/sdk": "1.10.2",
+		"@repo/mcp-common": "workspace:*",
+		"@repo/mcp-observability": "workspace:*",
+		"agents": "0.0.67",
+		"cloudflare": "4.2.0",
+		"hono": "4.7.6",
+		"zod": "3.24.2"
+	},
+	"devDependencies": {
+		"@cloudflare/vitest-pool-workers": "0.8.14",
+		"@types/jsonwebtoken": "9.0.9",
+		"@types/node": "22.14.1",
+		"prettier": "3.5.3",
+		"typescript": "5.5.4",
+		"vitest": "3.0.9",
+		"wrangler": "4.10.0"
+	}
+}

apps/cloudflare-one-access/src/access.app.ts

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+import OAuthProvider from '@cloudflare/workers-oauth-provider'
+import { McpAgent } from 'agents/mcp'
+
+import {
+	createAuthHandlers,
+	handleTokenExchangeCallback,
+} from '@repo/mcp-common/src/cloudflare-oauth-handler'
+import { handleDevMode } from '@repo/mcp-common/src/dev-mode'
+import { getUserDetails, UserDetails } from '@repo/mcp-common/src/durable-objects/user_details.do'
+import { getEnv } from '@repo/mcp-common/src/env'
+import { RequiredScopes } from '@repo/mcp-common/src/scopes'
+import { CloudflareMCPServer } from '@repo/mcp-common/src/server'
+import { registerAccountTools } from '@repo/mcp-common/src/tools/account.tools'
+import { MetricsTracker } from '@repo/mcp-observability'
+
+import { registerZeroTrustAccessTools } from './tools/access.tools'
+
+import type { AuthProps } from '@repo/mcp-common/src/cloudflare-oauth-handler'
+import type { Env } from './access.context'
+
+export { UserDetails }
+
+const env = getEnv<Env>()
+
+const metrics = new MetricsTracker(env.MCP_METRICS, {
+	name: env.MCP_SERVER_NAME,
+	version: env.MCP_SERVER_VERSION,
+})
+
+// Context from the auth process, encrypted & stored in the auth token
+// and provided to the DurableMCP as this.props
+type Props = AuthProps
+
+type State = { activeAccountId: string | null }
+
+export class ZeroTrustAccessMCP extends McpAgent<Env, State, Props> {
+	_server: CloudflareMCPServer | undefined
+	set server(server: CloudflareMCPServer) {
+		this._server = server
+	}
+
+	get server(): CloudflareMCPServer {
+		if (!this._server) {
+			throw new Error('Tried to access server before it was initialized')
+		}
+
+		return this._server
+	}
+
+	constructor(ctx: DurableObjectState, env: Env) {
+		super(ctx, env)
+	}
+
+	async init() {
+		this.server = new CloudflareMCPServer({
+			userId: this.props.user.id,
+			wae: this.env.MCP_METRICS,
+			serverInfo: {
+				name: this.env.MCP_SERVER_NAME,
+				version: this.env.MCP_SERVER_VERSION,
+			},
+		})
+
+		registerAccountTools(this)
+		registerZeroTrustAccessTools(this)
+	}
+
+	async getActiveAccountId() {
+		try {
+			// Get UserDetails Durable Object based off the userId and retrieve the activeAccountId from it
+			// we do this so we can persist activeAccountId across sessions
+			const userDetails = getUserDetails(env, this.props.user.id)
+			return await userDetails.getActiveAccountId()
+		} catch (e) {
+			this.server.recordError(e)
+			return null
+		}
+	}
+
+	async setActiveAccountId(accountId: string) {
+		try {
+			const userDetails = getUserDetails(env, this.props.user.id)
+			await userDetails.setActiveAccountId(accountId)
+		} catch (e) {
+			this.server.recordError(e)
+		}
+	}
+}
+
+const ZeroTrustGatewayScopes = {
+	...RequiredScopes,
+	'account:read': 'See your account info such as account details, analytics, and memberships.',
+	'teams:read': 'See Cloudflare One Resources',
+} as const
+
+export default {
+	fetch: async (req: Request, env: Env, ctx: ExecutionContext) => {
+		if (env.ENVIRONMENT === 'development' && env.DEV_DISABLE_OAUTH === 'true') {
+			return await handleDevMode(ZeroTrustAccessMCP, req, env, ctx)
+		}
+
+		return new OAuthProvider({
+			apiHandlers: {
+				'/mcp': ZeroTrustAccessMCP.serve('/mcp'),
+				'/sse': ZeroTrustAccessMCP.serveSSE('/sse'),
+			},
+			// @ts-ignore
+			defaultHandler: createAuthHandlers({ scopes: ZeroTrustAccessScopes, metrics }),
+			authorizeEndpoint: '/oauth/authorize',
+			tokenEndpoint: '/token',
+			tokenExchangeCallback: (options) =>
+				handleTokenExchangeCallback(
+					options,
+					env.CLOUDFLARE_CLIENT_ID,
+					env.CLOUDFLARE_CLIENT_SECRET
+				),
+			// Cloudflare access token TTL
+			accessTokenTTL: 3600,
+			clientRegistrationEndpoint: '/register',
+		}).fetch(req, env, ctx)
+	},
+}

apps/cloudflare-one-access/src/access.context.ts

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+import type { UserDetails, ZeroTrustAccessMCP } from './access.app'
+
+export interface Env {
+	ENVIRONMENT: 'development' | 'staging' | 'production'
+	MCP_SERVER_NAME: string
+	MCP_SERVER_VERSION: string
+	MCP_OBJECT: DurableObjectNamespace<ZeroTrustAccessMCP>
+	MCP_METRICS: AnalyticsEngineDataset
+	AI: Ai
+	CLOUDFLARE_CLIENT_ID: string
+	CLOUDFLARE_CLIENT_SECRET: string
+	USER_DETAILS: DurableObjectNamespace<UserDetails>
+	DEV_DISABLE_OAUTH: string
+	DEV_CLOUDFLARE_API_TOKEN: string
+	DEV_CLOUDFLARE_EMAIL: string
+}