diff --git a/__tests__/client.test.ts b/__tests__/client.test.ts
index 40ff3c0..2faa874 100644
--- a/__tests__/client.test.ts
+++ b/__tests__/client.test.ts
@@ -112,3 +112,30 @@ describe("post", () => {
     await expect(post("/api/test", {})).rejects.toThrow("Bad request");
   });
 });
+
+for (const [method, send] of [
+  ["GET", () => get("/api/test")],
+  ["POST", () => post("/api/test", {})],
+] as const) {
+  describe(`${method} response contract`, () => {
+    it.each([
+      [false, { error: "Preferred", message: "Other" }, "Preferred"],
+      [false, { message: "Rejected" }, "Rejected"],
+      [false, {}, "Request failed: 503"],
+      [true, { status: "error", message: "Application rejected" }, "Application rejected"],
+    ])("retains error precedence for HTTP ok=%s and %j", async (ok, data, message) => {
+      mockFetch.mockResolvedValue({ ok, status: 503, json: async () => data });
+      await expect(send()).rejects.toThrow(message);
+    });
+
+    it("propagates an invalid JSON response without retrying", async () => {
+      mockFetch.mockClear();
+      mockFetch.mockResolvedValue({
+        ok: false,
+        json: async () => { throw new SyntaxError("Invalid JSON"); },
+      });
+      await expect(send()).rejects.toThrow("Invalid JSON");
+      expect(mockFetch).toHaveBeenCalledTimes(1);
+    });
+  });
+}
diff --git a/src/client.ts b/src/client.ts
index d2d326a..d7239bc 100644
--- a/src/client.ts
+++ b/src/client.ts
@@ -7,22 +7,12 @@ export interface ApiResponse {
   [key: string]: unknown;
 }
 
-export async function get(
-  path: string,
-  params?: Record<string, string>,
+async function request(
+  url: URL,
+  options: Pick<RequestInit, "method" | "body">,
 ): Promise<ApiResponse> {
-  const baseUrl = getBaseUrl();
-  const url = new URL(path, baseUrl);
-  if (params) {
-    for (const [key, value] of Object.entries(params)) {
-      if (value !== undefined && value !== "") {
-        url.searchParams.set(key, value);
-      }
-    }
-  }
-
   const response = await fetch(url.toString(), {
-    method: "GET",
+    ...options,
     headers: {
       "x-api-key": getApiKey(),
       "Content-Type": "application/json",
@@ -38,27 +28,28 @@ export async function get(
   return data;
 }
 
+export async function get(
+  path: string,
+  params?: Record<string, string>,
+): Promise<ApiResponse> {
+  const url = new URL(path, getBaseUrl());
+  if (params) {
+    for (const [key, value] of Object.entries(params)) {
+      if (value !== undefined && value !== "") {
+        url.searchParams.set(key, value);
+      }
+    }
+  }
+
+  return request(url, { method: "GET" });
+}
+
 export async function post(
   path: string,
   body: Record<string, unknown>,
 ): Promise<ApiResponse> {
-  const baseUrl = getBaseUrl();
-  const url = new URL(path, baseUrl);
-
-  const response = await fetch(url.toString(), {
+  return request(new URL(path, getBaseUrl()), {
     method: "POST",
-    headers: {
-      "x-api-key": getApiKey(),
-      "Content-Type": "application/json",
-    },
     body: JSON.stringify(body),
   });
-
-  const data: ApiResponse = await response.json();
-
-  if (!response.ok || data.status === "error") {
-    throw new Error(data.error || data.message || `Request failed: ${response.status}`);
-  }
-
-  return data;
 }