diff --git a/packages/agent/src/server/agent-server.configure-environment.test.ts b/packages/agent/src/server/agent-server.configure-environment.test.ts
new file mode 100644
index 000000000..e7d903b86
--- /dev/null
+++ b/packages/agent/src/server/agent-server.configure-environment.test.ts
@@ -0,0 +1,97 @@
+import { afterEach, beforeEach, describe, expect, it } from "vitest";
+import { AgentServer } from "./agent-server";
+
+interface TestableServer {
+  configureEnvironment(args?: { isInternal?: boolean }): void;
+}
+
+const ENV_KEYS_UNDER_TEST = [
+  "LLM_GATEWAY_URL",
+  "ANTHROPIC_BASE_URL",
+  "OPENAI_BASE_URL",
+] as const;
+
+describe("AgentServer.configureEnvironment", () => {
+  const originalEnv: Partial<Record<string, string | undefined>> = {};
+
+  beforeEach(() => {
+    for (const key of ENV_KEYS_UNDER_TEST) {
+      originalEnv[key] = process.env[key];
+      delete process.env[key];
+    }
+  });
+
+  afterEach(() => {
+    for (const key of ENV_KEYS_UNDER_TEST) {
+      const value = originalEnv[key];
+      if (value === undefined) {
+        delete process.env[key];
+      } else {
+        process.env[key] = value;
+      }
+    }
+  });
+
+  const buildServer = (mode: "background" | "interactive"): TestableServer =>
+    new AgentServer({
+      port: 0,
+      jwtPublicKey: "test-key",
+      apiUrl: "https://us.posthog.com",
+      apiKey: "test-api-key",
+      projectId: 1,
+      mode,
+      taskId: "test-task-id",
+      runId: "test-run-id",
+    }) as unknown as TestableServer;
+
+  it("tags as background_agents when the task is internal", () => {
+    buildServer("interactive").configureEnvironment({ isInternal: true });
+
+    expect(process.env.LLM_GATEWAY_URL).toBe(
+      "https://gateway.us.posthog.com/background_agents",
+    );
+    expect(process.env.ANTHROPIC_BASE_URL).toBe(
+      "https://gateway.us.posthog.com/background_agents",
+    );
+    expect(process.env.OPENAI_BASE_URL).toBe(
+      "https://gateway.us.posthog.com/background_agents/v1",
+    );
+  });
+
+  it("tags as posthog_code when the task is not internal", () => {
+    buildServer("background").configureEnvironment({ isInternal: false });
+
+    expect(process.env.LLM_GATEWAY_URL).toBe(
+      "https://gateway.us.posthog.com/posthog_code",
+    );
+  });
+
+  it("tags as posthog_code when isInternal is omitted (getTask failure fallback)", () => {
+    buildServer("background").configureEnvironment();
+
+    expect(process.env.LLM_GATEWAY_URL).toBe(
+      "https://gateway.us.posthog.com/posthog_code",
+    );
+  });
+
+  it("ignores mode when picking the gateway product", () => {
+    buildServer("background").configureEnvironment({ isInternal: false });
+    const fromBackground = process.env.LLM_GATEWAY_URL;
+
+    buildServer("interactive").configureEnvironment({ isInternal: false });
+    const fromInteractive = process.env.LLM_GATEWAY_URL;
+
+    expect(fromBackground).toBe(fromInteractive);
+    expect(fromBackground).toBe("https://gateway.us.posthog.com/posthog_code");
+  });
+
+  it("respects the LLM_GATEWAY_URL override regardless of internal flag", () => {
+    process.env.LLM_GATEWAY_URL = "http://ngrok.test/proxy";
+
+    buildServer("background").configureEnvironment({ isInternal: true });
+
+    expect(process.env.LLM_GATEWAY_URL).toBe("http://ngrok.test/proxy");
+    expect(process.env.ANTHROPIC_BASE_URL).toBe("http://ngrok.test/proxy");
+    expect(process.env.OPENAI_BASE_URL).toBe("http://ngrok.test/proxy/v1");
+  });
+});
diff --git a/packages/agent/src/server/agent-server.ts b/packages/agent/src/server/agent-server.ts
index 9e5425fc9..b614d5c69 100644
--- a/packages/agent/src/server/agent-server.ts
+++ b/packages/agent/src/server/agent-server.ts
@@ -46,7 +46,7 @@ import type {
 } from "../types";
 import { resourceLink } from "../utils/acp-content";
 import { AsyncMutex } from "../utils/async-mutex";
-import { getLlmGatewayUrl } from "../utils/gateway";
+import { type GatewayProduct, getLlmGatewayUrl } from "../utils/gateway";
 import { Logger } from "../utils/logger";
 import { logAgentshRuntimeInfo } from "./agentsh-runtime";
 import {
@@ -778,8 +778,6 @@ export class AgentServer {
       name: process.env.HOSTNAME || "cloud-sandbox",
     };
 
-    this.configureEnvironment();
-
     const [preTaskRun, preTask] = await Promise.all([
       this.posthogAPI
         .getTaskRun(payload.task_id, payload.run_id)
@@ -800,6 +798,8 @@ export class AgentServer {
       }),
     ]);
 
+    this.configureEnvironment({ isInternal: preTask?.internal === true });
+
     const prUrl = getTaskRunStateString(preTaskRun, "slack_notified_pr_url");
 
     if (prUrl) {
@@ -1710,10 +1710,15 @@ ${attributionInstructions}
     }
   }
 
-  private configureEnvironment(): void {
+  private configureEnvironment({
+    isInternal = false,
+  }: {
+    isInternal?: boolean;
+  } = {}): void {
     const { apiKey, apiUrl, projectId } = this.config;
-    const product =
-      this.config.mode === "background" ? "background_agents" : "posthog_code";
+    const product: GatewayProduct = isInternal
+      ? "background_agents"
+      : "posthog_code";
     const gatewayUrl =
       process.env.LLM_GATEWAY_URL || getLlmGatewayUrl(apiUrl, product);
     const openaiBaseUrl = gatewayUrl.endsWith("/v1")
diff --git a/packages/agent/src/types.ts b/packages/agent/src/types.ts
index 00a904f56..18e5572c0 100644
--- a/packages/agent/src/types.ts
+++ b/packages/agent/src/types.ts
@@ -41,6 +41,7 @@ export interface Task {
   github_integration?: number | null;
   repository: string; // Format: "organization/repository" (e.g., "posthog/posthog-js")
   json_schema?: Record<string, unknown> | null; // JSON schema for task output validation
+  internal?: boolean;
   created_at: string;
   updated_at: string;
   created_by?: {