diff --git a/tools/server/webui/src/lib/config/mcp.ts b/tools/server/webui/src/lib/config/mcp.ts
index 83e08ae557..b85851d06f 100644
--- a/tools/server/webui/src/lib/config/mcp.ts
+++ b/tools/server/webui/src/lib/config/mcp.ts
@@ -34,12 +34,14 @@ export function parseMcpServerSettings(
 		);
 
 		const url = typeof entry?.url === 'string' ? entry.url.trim() : '';
+		const headers = typeof entry?.headers === 'string' ? entry.headers.trim() : undefined;
 
 		return {
 			id: generateMcpServerId((entry as { id?: unknown })?.id, index),
 			enabled: Boolean((entry as { enabled?: unknown })?.enabled),
 			url,
-			requestTimeoutSeconds
+			requestTimeoutSeconds,
+			headers: headers || undefined
 		} satisfies MCPServerSettingsEntry;
 	});
 }
@@ -52,11 +54,25 @@ function buildServerConfig(
 		return undefined;
 	}
 
+	// Parse custom headers if provided
+	let headers: Record<string, string> | undefined;
+	if (entry.headers) {
+		try {
+			const parsed = JSON.parse(entry.headers);
+			if (typeof parsed === 'object' && parsed !== null && !Array.isArray(parsed)) {
+				headers = parsed as Record<string, string>;
+			}
+		} catch {
+			console.warn('[MCP] Failed to parse custom headers JSON, ignoring:', entry.headers);
+		}
+	}
+
 	return {
 		url: entry.url,
 		transport: detectMcpTransportFromUrl(entry.url),
 		handshakeTimeoutMs: connectionTimeoutMs,
-		requestTimeoutMs: Math.round(entry.requestTimeoutSeconds * 1000)
+		requestTimeoutMs: Math.round(entry.requestTimeoutSeconds * 1000),
+		headers
 	};
 }
 
diff --git a/tools/server/webui/src/lib/mcp/client.ts b/tools/server/webui/src/lib/mcp/client.ts
index 5386483524..3f2b4ce411 100644
--- a/tools/server/webui/src/lib/mcp/client.ts
+++ b/tools/server/webui/src/lib/mcp/client.ts
@@ -78,6 +78,69 @@ export class MCPClient {
 		return Array.from(this.toolsToServer.keys());
 	}
 
+	/**
+	 * Normalize JSON Schema properties to ensure all have explicit types.
+	 * Infers type from default value if missing - fixes compatibility with
+	 * llama.cpp which requires explicit types in tool schemas.
+	 */
+	private normalizeSchemaProperties(schema: Record<string, unknown>): Record<string, unknown> {
+		if (!schema || typeof schema !== 'object') return schema;
+
+		const normalized = { ...schema };
+
+		// Process properties object
+		if (normalized.properties && typeof normalized.properties === 'object') {
+			const props = normalized.properties as Record<string, Record<string, unknown>>;
+			const normalizedProps: Record<string, Record<string, unknown>> = {};
+
+			for (const [key, prop] of Object.entries(props)) {
+				if (!prop || typeof prop !== 'object') {
+					normalizedProps[key] = prop;
+					continue;
+				}
+
+				const normalizedProp = { ...prop };
+
+				// Infer type from default if missing
+				if (!normalizedProp.type && normalizedProp.default !== undefined) {
+					const defaultVal = normalizedProp.default;
+					if (typeof defaultVal === 'string') {
+						normalizedProp.type = 'string';
+					} else if (typeof defaultVal === 'number') {
+						normalizedProp.type = Number.isInteger(defaultVal) ? 'integer' : 'number';
+					} else if (typeof defaultVal === 'boolean') {
+						normalizedProp.type = 'boolean';
+					} else if (Array.isArray(defaultVal)) {
+						normalizedProp.type = 'array';
+					} else if (typeof defaultVal === 'object' && defaultVal !== null) {
+						normalizedProp.type = 'object';
+					}
+				}
+
+				// Recursively normalize nested schemas
+				if (normalizedProp.properties) {
+					Object.assign(
+						normalizedProp,
+						this.normalizeSchemaProperties(normalizedProp as Record<string, unknown>)
+					);
+				}
+
+				// Normalize items in array schemas
+				if (normalizedProp.items && typeof normalizedProp.items === 'object') {
+					normalizedProp.items = this.normalizeSchemaProperties(
+						normalizedProp.items as Record<string, unknown>
+					);
+				}
+
+				normalizedProps[key] = normalizedProp;
+			}
+
+			normalized.properties = normalizedProps;
+		}
+
+		return normalized;
+	}
+
 	async getToolsDefinition(): Promise<
 		{
 			type: 'function';
@@ -91,16 +154,21 @@ export class MCPClient {
 
 		for (const [, server] of this.servers) {
 			for (const tool of server.tools) {
+				const rawSchema = (tool.inputSchema as Record<string, unknown>) ?? {
+					type: 'object',
+					properties: {},
+					required: []
+				};
+
+				// Normalize schema to fix missing types
+				const normalizedSchema = this.normalizeSchemaProperties(rawSchema);
+
 				tools.push({
 					type: 'function',
 					function: {
 						name: tool.name,
 						description: tool.description,
-						parameters: (tool.inputSchema as Record<string, unknown>) ?? {
-							type: 'object',
-							properties: {},
-							required: []
-						}
+						parameters: normalizedSchema
 					}
 				});
 			}
diff --git a/tools/server/webui/src/lib/mcp/host-manager.ts b/tools/server/webui/src/lib/mcp/host-manager.ts
index 73181a6de3..84df0afd32 100644
--- a/tools/server/webui/src/lib/mcp/host-manager.ts
+++ b/tools/server/webui/src/lib/mcp/host-manager.ts
@@ -178,23 +178,93 @@ export class MCPHostManager {
 		return allTools;
 	}
 
+	/**
+	 * Normalize JSON Schema properties to ensure all have explicit types.
+	 * Infers type from default value if missing - fixes compatibility with
+	 * llama.cpp which requires explicit types in tool schemas.
+	 */
+	private normalizeSchemaProperties(schema: Record<string, unknown>): Record<string, unknown> {
+		if (!schema || typeof schema !== 'object') return schema;
+
+		const normalized = { ...schema };
+
+		// Process properties object
+		if (normalized.properties && typeof normalized.properties === 'object') {
+			const props = normalized.properties as Record<string, Record<string, unknown>>;
+			const normalizedProps: Record<string, Record<string, unknown>> = {};
+
+			for (const [key, prop] of Object.entries(props)) {
+				if (!prop || typeof prop !== 'object') {
+					normalizedProps[key] = prop;
+					continue;
+				}
+
+				const normalizedProp = { ...prop };
+
+				// Infer type from default if missing
+				if (!normalizedProp.type && normalizedProp.default !== undefined) {
+					const defaultVal = normalizedProp.default;
+					if (typeof defaultVal === 'string') {
+						normalizedProp.type = 'string';
+					} else if (typeof defaultVal === 'number') {
+						normalizedProp.type = Number.isInteger(defaultVal) ? 'integer' : 'number';
+					} else if (typeof defaultVal === 'boolean') {
+						normalizedProp.type = 'boolean';
+					} else if (Array.isArray(defaultVal)) {
+						normalizedProp.type = 'array';
+					} else if (typeof defaultVal === 'object' && defaultVal !== null) {
+						normalizedProp.type = 'object';
+					}
+				}
+
+				// Recursively normalize nested schemas
+				if (normalizedProp.properties) {
+					Object.assign(
+						normalizedProp,
+						this.normalizeSchemaProperties(normalizedProp as Record<string, unknown>)
+					);
+				}
+
+				// Normalize items in array schemas
+				if (normalizedProp.items && typeof normalizedProp.items === 'object') {
+					normalizedProp.items = this.normalizeSchemaProperties(
+						normalizedProp.items as Record<string, unknown>
+					);
+				}
+
+				normalizedProps[key] = normalizedProp;
+			}
+
+			normalized.properties = normalizedProps;
+		}
+
+		return normalized;
+	}
+
 	/**
 	 * Returns tools in OpenAI function calling format.
 	 * Ready to be sent to /v1/chat/completions API.
 	 */
 	getToolDefinitionsForLLM(): OpenAIToolDefinition[] {
-		return this.getAllTools().map((tool) => ({
-			type: 'function' as const,
-			function: {
-				name: tool.name,
-				description: tool.description,
-				parameters: (tool.inputSchema as Record<string, unknown>) ?? {
-					type: 'object',
-					properties: {},
-					required: []
+		return this.getAllTools().map((tool) => {
+			const rawSchema = (tool.inputSchema as Record<string, unknown>) ?? {
+				type: 'object',
+				properties: {},
+				required: []
+			};
+
+			// Normalize schema to fix missing types
+			const normalizedSchema = this.normalizeSchemaProperties(rawSchema);
+
+			return {
+				type: 'function' as const,
+				function: {
+					name: tool.name,
+					description: tool.description,
+					parameters: normalizedSchema
 				}
-			}
-		}));
+			};
+		});
 	}
 
 	/**
diff --git a/tools/server/webui/src/lib/types/mcp.ts b/tools/server/webui/src/lib/types/mcp.ts
index dbbff703e5..82e168f254 100644
--- a/tools/server/webui/src/lib/types/mcp.ts
+++ b/tools/server/webui/src/lib/types/mcp.ts
@@ -75,4 +75,10 @@ export type MCPServerSettingsEntry = {
 	enabled: boolean;
 	url: string;
 	requestTimeoutSeconds: number;
+	/** Optional custom HTTP headers (JSON string of key-value pairs). */
+	headers?: string;
+	/** Server name from metadata (fetched during health check). */
+	name?: string;
+	/** Server icon URL from metadata (fetched during health check). */
+	iconUrl?: string;
 };