diff --git a/src/common/config/userConfig.ts b/src/common/config/userConfig.ts
index 661e0046..bb52e1ea 100644
--- a/src/common/config/userConfig.ts
+++ b/src/common/config/userConfig.ts
@@ -113,10 +113,10 @@ export const UserConfigSchema = z4.object({
     httpPort: z4.coerce
         .number()
         .int()
-        .min(1, "Invalid httpPort: must be at least 1")
+        .min(0, "Invalid httpPort: must be at least 0")
         .max(65535, "Invalid httpPort: must be at most 65535")
         .default(3000)
-        .describe("Port number for the HTTP server (only used when transport is 'http').")
+        .describe("Port number for the HTTP server (only used when transport is 'http'). Use 0 for a random port.")
         .register(configRegistry, { overrideBehavior: "not-allowed" }),
     httpHost: z4
         .string()
@@ -125,7 +125,7 @@ export const UserConfigSchema = z4.object({
         .register(configRegistry, { overrideBehavior: "not-allowed" }),
     httpHeaders: z4
         .object({})
-        .passthrough()
+        .loose()
         .default({})
         .describe(
             "Header that the HTTP server will validate when making requests (only used when transport is 'http')."
diff --git a/src/lib.ts b/src/lib.ts
index babdbde7..a1d8532d 100644
--- a/src/lib.ts
+++ b/src/lib.ts
@@ -1,6 +1,6 @@
 export { Server, type ServerOptions } from "./server.js";
 export { Session, type SessionOptions } from "./common/session.js";
-export { type UserConfig } from "./common/config/userConfig.js";
+export { type UserConfig, UserConfigSchema } from "./common/config/userConfig.js";
 export { LoggerBase, type LogPayload, type LoggerType, type LogLevel } from "./common/logger.js";
 export { StreamableHttpRunner } from "./transports/streamableHttp.js";
 export { StdioRunner } from "./transports/stdio.js";
diff --git a/tests/unit/common/config.test.ts b/tests/unit/common/config.test.ts
index c5f537d2..a8cd5f18 100644
--- a/tests/unit/common/config.test.ts
+++ b/tests/unit/common/config.test.ts
@@ -690,17 +690,17 @@ describe("config", () => {
         });
 
         describe("httpPort", () => {
-            it("must be above 1", () => {
+            it("must be above 0", () => {
                 const onErrorFn = vi.fn();
                 const onExitFn = vi.fn<CreateUserConfigHelpers["closeProcess"]>();
                 createUserConfig({
                     onError: onErrorFn,
                     closeProcess: onExitFn,
-                    cliArguments: ["--httpPort", "0"],
+                    cliArguments: ["--httpPort", "-1"],
                 });
                 expect(onErrorFn).toBeCalledWith(
                     expect.stringContaining(
-                        "Invalid configuration for the following fields:\nhttpPort - Invalid httpPort: must be at least 1"
+                        "Invalid configuration for the following fields:\nhttpPort - Invalid httpPort: must be at least 0"
                     )
                 );
                 expect(onExitFn).toBeCalledWith(1);