diff --git a/src/extension.ts b/src/extension.ts
index 8fa37fb..0095ef1 100644
--- a/src/extension.ts
+++ b/src/extension.ts
@@ -14,6 +14,9 @@ let OPENCREDITS_API_URL = 'https://ccc.api.opencredits.ai';
 let OPENCREDITS_WEB_URL = 'https://ccc.opencredits.ai';
 let OPENCREDITS_PUBLISHABLE_KEY = 'oc_pk_c43da4f9a9484ae484ad29bc97cc354f';
 
+// Base URL substrings that identify a known first-party endpoint (OpenCredits/router)
+const KNOWN_ENDPOINT_MARKERS = ['opencredits.ai', 'localhost:8787'];
+
 const exec = util.promisify(cp.exec);
 
 // Storage for diff content (used by DiffContentProvider)
@@ -289,8 +292,8 @@ class ClaudeChatProvider {
 			return false;
 		}
 		const envVars = config.get<Record<string, string>>('environment.variables', {});
-		const baseUrl = envVars['ANTHROPIC_BASE_URL'] || '';
-		return baseUrl.includes('opencredits.ai') || baseUrl.includes('localhost:8787');
+		const baseUrl = (envVars['ANTHROPIC_BASE_URL'] || '').toLowerCase();
+		return KNOWN_ENDPOINT_MARKERS.some(marker => baseUrl.includes(marker));
 	}
 
 	private async _setEnvsDisabled(disabled: boolean): Promise<void> {
@@ -1679,15 +1682,31 @@ class ClaudeChatProvider {
 		return text.includes('Failed to authenticate. API Error: 401 Invalid authentication credentials');
 	}
 
+	// A custom (non-Anthropic, non-OpenCredits/router) endpoint may return its
+	// own error text that happens to contain one of the broad login patterns
+	// below (e.g. a relay pointing users to its own '/login' page). In that
+	// case only the strict, exact-match check should be trusted.
+	private _hasCustomAnthropicEndpoint(): boolean {
+		const config = vscode.workspace.getConfiguration('claudeCodeChat');
+		const envsDisabled = config.get<boolean>('environment.disabled', false);
+		const envVars = envsDisabled ? {} : config.get<Record<string, string>>('environment.variables', {});
+		const baseUrl = (envVars['ANTHROPIC_BASE_URL'] || process.env.ANTHROPIC_BASE_URL || '').trim().toLowerCase();
+		if (!baseUrl) { return false; }
+		if (baseUrl.includes('api.anthropic.com')) { return false; }
+		if (KNOWN_ENDPOINT_MARKERS.some(marker => baseUrl.includes(marker))) { return false; }
+		return true;
+	}
+
 	// Broader login-required signals — only trusted when they arrive on an
 	// error result, since these phrases can appear in benign explanations.
 	private _isLoginErrorResult(text: unknown): boolean {
 		if (typeof text !== 'string' || !text) { return false; }
 		if (this._isLoginError(text)) { return true; }
+		if (this._hasCustomAnthropicEndpoint()) { return false; }
 		const patterns = [
 			'Invalid API key',
 			'Not logged in',
-			'/login',
+			'Please run /login',
 			'not authenticated'
 		];
 		return patterns.some(pattern => text.includes(pattern));
diff --git a/src/script.ts b/src/script.ts
index 4c949e2..57c1be1 100644
--- a/src/script.ts
+++ b/src/script.ts
@@ -2119,6 +2119,7 @@ const getScript = (isTelemetryEnabled: boolean, opencreditsApiUrl: string = 'htt
 		let hasOpenCreditsKey = false; // Whether OpenCredits key exists in env vars
 		let openCreditsBalance = null; // OpenCredits account balance
 		let envsDisabled = false; // Whether custom env vars are disabled
+		const OPENCREDITS_BASE_URL_MARKERS = ['opencredits', 'localhost:8787']; // Base URL substrings identifying an OpenCredits-style endpoint
 		let opencreditsEnabled = false; // Feature flag: whether OpenCredits is available in this region
 		let hasSavedOpenCreditsKey = false; // Whether a key exists in encrypted storage
 
@@ -4871,9 +4872,9 @@ const getScript = (isTelemetryEnabled: boolean, opencreditsApiUrl: string = 'htt
 			document.getElementById('wslOptions').style.display = wslEnabled ? 'block' : 'none';
 
 			// Update OpenCredits state from current env vars
-			const baseUrl = envVariables['ANTHROPIC_BASE_URL'] || '';
+			const baseUrl = (envVariables['ANTHROPIC_BASE_URL'] || '').toLowerCase();
 			const wasOpenCredits = hasOpenCreditsKey;
-			hasOpenCreditsKey = !!(baseUrl && (baseUrl.includes('opencredits') || baseUrl.includes('localhost:8787')));
+			hasOpenCreditsKey = !!(baseUrl && OPENCREDITS_BASE_URL_MARKERS.some(function(marker) { return baseUrl.includes(marker); }));
 			if (!hasOpenCreditsKey) {
 				openCreditsBalance = null;
 				// If a OpenCredits model was selected, revert to default
@@ -5199,7 +5200,8 @@ const getScript = (isTelemetryEnabled: boolean, opencreditsApiUrl: string = 'htt
 				envsDisabled = !!(message.data['environment.disabled']);
 				const envVars = message.data['environment.variables'] || {};
 				const wasOpenCreditsSettings = hasOpenCreditsKey;
-				hasOpenCreditsKey = !!(message.data['isOpenCredits'] || (!envsDisabled && envVars['ANTHROPIC_BASE_URL'] && (envVars['ANTHROPIC_BASE_URL'].includes('opencredits') || envVars['ANTHROPIC_BASE_URL'].includes('localhost:8787'))));
+				const settingsBaseUrl = (envVars['ANTHROPIC_BASE_URL'] || '').toLowerCase();
+				hasOpenCreditsKey = !!(message.data['isOpenCredits'] || (!envsDisabled && settingsBaseUrl && OPENCREDITS_BASE_URL_MARKERS.some(function(marker) { return settingsBaseUrl.includes(marker); })));
 
 				// Show/hide provider exclusion based on OpenCredits
 				var providerSection = document.getElementById('providerExclusionSection');