trying a MCP fix

Author: gary149

src/lib/server/textGeneration/mcp/runMcpFlow.ts

@@ -43,6 +43,10 @@ export async function* runMcpFlow({
 > {
 	// Start from env-configured servers
 	let servers = getMcpServers();
+	logger.debug(
+		{ servers: servers.map((s) => ({ name: s.name, url: s.url })) },
+		"[mcp] loaded servers from env"
+	);
 
 	// Merge in request-provided custom servers (if any)
 	try {
@@ -68,27 +72,53 @@ export async function* runMcpFlow({
 			servers = [...byName.values()];
 		}
 
-		// If the client specified a selection by name, filter to those
+		// If the client specified a non-empty selection by name, filter to those
 		const names = Array.isArray(reqMcp?.selectedServerNames)
 			? reqMcp?.selectedServerNames
 			: undefined;
-		if (Array.isArray(names)) {
+		if (Array.isArray(names) && names.length > 0) {
+			logger.debug(
+				{ selectedNames: names, beforeFilter: servers.length },
+				"[mcp] filtering servers by name"
+			);
 			servers = servers.filter((s) => names.includes(s.name));
+			logger.debug({ afterFilter: servers.length }, "[mcp] servers after name filter");
+		} else if (Array.isArray(names) && names.length === 0) {
+			// Be resilient: an empty array means "no explicit selection"; do not filter.
+			logger.debug("[mcp] empty selectedServerNames provided; skipping name filter");
 		}
 	} catch {
 		// ignore selection merge errors and proceed with env servers
 	}
 
+	// If no servers remain after selection/merge, exit early with an accurate message
+	if (servers.length === 0) {
+		logger.warn("[mcp] no MCP servers available after selection; skipping MCP flow");
+		return false;
+	}
+
 	// Enforce server-side safety (public HTTPS only, no private ranges)
+	const beforeFilter = servers.length;
 	servers = servers.filter((s) => {
 		try {
-			return isValidUrl(s.url);
-		} catch {
+			const isValid = isValidUrl(s.url);
+			if (!isValid) {
+				logger.warn({ name: s.name, url: s.url }, "[mcp] server rejected by URL safety");
+			}
+			return isValid;
+		} catch (err) {
+			logger.warn(
+				{ name: s.name, url: s.url, error: String(err) },
+				"[mcp] server URL validation error"
+			);
 			return false;
 		}
 	});
 	if (servers.length === 0) {
-		logger.warn("[mcp] all selected servers rejected by URL safety guard");
+		logger.warn(
+			{ beforeFilter, afterFilter: servers.length },
+			"[mcp] all servers rejected by URL safety guard"
+		);
 		return false;
 	}
 

src/lib/utils/messageUpdates.ts

@@ -13,7 +13,7 @@ import {
 import { page } from "$app/state";
 import type { KeyValuePair } from "$lib/types/Tool";
 
-type MessageUpdateRequestOptions = {
+export type MessageUpdateRequestOptions = {
 	base: string;
 	inputs?: string;
 	messageId?: string;

src/routes/conversation/[id]/+page.svelte

@@ -7,7 +7,8 @@
 	import { beforeNavigate, invalidateAll } from "$app/navigation";
 	import { base } from "$app/paths";
 	import { ERROR_MESSAGES, error } from "$lib/stores/errors";
-	import { findCurrentModel } from "$lib/utils/models";
+    import { findCurrentModel } from "$lib/utils/models";
+    import type { MessageUpdateRequestOptions } from "$lib/utils/messageUpdates";
 	import type { Message } from "$lib/types/Message";
 	import { MessageUpdateStatus, MessageUpdateType } from "$lib/types/MessageUpdate";
 	import titleUpdate from "$lib/stores/titleUpdate";
@@ -212,21 +213,23 @@
 
 			const messageUpdatesAbortController = new AbortController();
 
+			// Build payload and only include selectedMcpServerNames when non-empty
+			const enabled = $enabledServers;
+			const payload: MessageUpdateRequestOptions = {
+				base,
+				inputs: prompt,
+				messageId,
+				isRetry,
+				files: isRetry ? userMessage?.files : base64Files,
+				selectedMcpServers: enabled.map((s) => ({ name: s.name, url: s.url, headers: s.headers })),
+			};
+			if (enabled.length > 0) {
+				payload.selectedMcpServerNames = enabled.map((s) => s.name);
+			}
+
 			const messageUpdatesIterator = await fetchMessageUpdates(
 				page.params.id,
-				{
-					base,
-					inputs: prompt,
-					messageId,
-					isRetry,
-					files: isRetry ? userMessage?.files : base64Files,
-					selectedMcpServerNames: $enabledServers.map((s) => s.name),
-					selectedMcpServers: $enabledServers.map((s) => ({
-						name: s.name,
-						url: s.url,
-						headers: s.headers,
-					})),
-				},
+				payload,
 				messageUpdatesAbortController.signal
 			).catch((err) => {
 				error.set(err.message);