Adds searxng support for tool calling

server/src/env.ts

@@ -1,5 +1,24 @@
+import path from "node:path";
+import { fileURLToPath } from "node:url";
+import { config as loadDotenv } from "dotenv";
 import { z } from "zod";
-import "dotenv/config";
+
+loadDotenv({ quiet: true });
+loadDotenv({ path: path.resolve(path.dirname(fileURLToPath(import.meta.url)), "../../.env"), quiet: true });
+
+const OptionalUrlSchema = z.preprocess(
+  (value) => (typeof value === "string" && value.trim() === "" ? undefined : value),
+  z.string().trim().url().optional()
+);
+
+const ChatWebSearchEngineSchema = z.preprocess(
+  (value) => {
+    if (typeof value !== "string") return value;
+    const trimmed = value.trim();
+    return trimmed ? trimmed.toLowerCase() : undefined;
+  },
+  z.enum(["exa", "searxng"]).default("exa")
+);
 
 const EnvSchema = z.object({
   PORT: z.coerce.number().int().positive().default(8787),
@@ -13,6 +32,18 @@ const EnvSchema = z.object({
   ANTHROPIC_API_KEY: z.string().optional(),
   XAI_API_KEY: z.string().optional(),
   EXA_API_KEY: z.string().optional(),
+
+  // Chat-mode web_search tool configuration. Search mode remains Exa-only for now.
+  CHAT_WEB_SEARCH_ENGINE: ChatWebSearchEngineSchema,
+  SEARXNG_BASE_URL: OptionalUrlSchema,
+}).superRefine((value, ctx) => {
+  if (value.CHAT_WEB_SEARCH_ENGINE === "searxng" && !value.SEARXNG_BASE_URL) {
+    ctx.addIssue({
+      code: "custom",
+      path: ["SEARXNG_BASE_URL"],
+      message: "SEARXNG_BASE_URL is required when CHAT_WEB_SEARCH_ENGINE=searxng",
+    });
+  }
 });
 
 export type Env = z.infer<typeof EnvSchema>;