Use MCP_CONFORMANCE_SCENARIO env var in auth-test client

Update auth-test.ts and test helper to use the new MCP_CONFORMANCE_SCENARIO
env var instead of putting scenario in the context object. This aligns with
the everything-client pattern from PR #54.

Author: pcarleton

examples/clients/typescript/auth-test.ts

@@ -27,7 +27,6 @@ const CIMD_CLIENT_METADATA_URL =
  * See: https://github.com/modelcontextprotocol/conformance/issues/51
  */
 interface ConformanceContext {
-  scenario: string;
   client_id?: string;
   // For JWT auth (private_key_jwt)
   private_key_pem?: string;
@@ -44,7 +43,8 @@ function getContext(
   }
   const contextJson = process.env.MCP_CONFORMANCE_CONTEXT;
   if (!contextJson) {
-    throw new Error('MCP_CONFORMANCE_CONTEXT environment variable is required');
+    // Context is optional - only needed for client credentials scenarios
+    return {};
   }
   return JSON.parse(contextJson);
 }
@@ -53,10 +53,9 @@ function getContext(
  * Create an OAuth provider based on the scenario type.
  */
 function createProviderForScenario(
+  scenario: string,
   context: ConformanceContext
 ): OAuthClientProvider | undefined {
-  const { scenario } = context;
-
   // Client credentials scenarios use the dedicated provider classes
   if (scenario === 'auth/client-credentials-jwt') {
     if (
@@ -101,7 +100,15 @@ export async function runClient(
   serverUrl: string,
   passedContext?: Record<string, unknown>
 ): Promise<void> {
+  const scenario = process.env.MCP_CONFORMANCE_SCENARIO;
+  if (!scenario) {
+    throw new Error(
+      'MCP_CONFORMANCE_SCENARIO environment variable is required'
+    );
+  }
+
   const context = getContext(passedContext);
+  logger.debug('Scenario:', scenario);
   logger.debug('Parsed context:', JSON.stringify(context, null, 2));
 
   const client = new Client(
@@ -110,7 +117,10 @@ export async function runClient(
   );
 
   // Check if this is a client credentials scenario
-  const clientCredentialsProvider = createProviderForScenario(context);
+  const clientCredentialsProvider = createProviderForScenario(
+    scenario,
+    context
+  );
 
   let transport: StreamableHTTPClientTransport;
 

src/scenarios/client/auth/test_helpers/testClient.ts

@@ -125,11 +125,12 @@ export async function runClientAgainstScenario(
   const urls = await scenario.start();
   const serverUrl = urls.serverUrl;
 
-  // Build context with scenario name
-  const context = {
-    ...urls.context,
-    scenario: scenarioName
-  };
+  // Context contains scenario-specific data (credentials, etc.)
+  const context = urls.context;
+
+  // Set scenario env var for inline runners
+  const previousScenario = process.env.MCP_CONFORMANCE_SCENARIO;
+  process.env.MCP_CONFORMANCE_SCENARIO = scenarioName;
 
   try {
     // Run the client
@@ -191,6 +192,12 @@ export async function runClientAgainstScenario(
       }
     }
   } finally {
+    // Restore previous env var
+    if (previousScenario !== undefined) {
+      process.env.MCP_CONFORMANCE_SCENARIO = previousScenario;
+    } else {
+      delete process.env.MCP_CONFORMANCE_SCENARIO;
+    }
     // Stop the scenario server
     await scenario.stop();
   }