refactor(billing): drop extractGatedModel; the gate copy doesn't name the model

The regex existed only to fish the model id back out of our own error prose
so the modal could name it — and the session path only ever sees the
stringified message, so even a structured gateway field would need the same
string-fishing. The user just sent a message on the model they picked, so
"This model isn't included in the free tier" is unambiguous. Deletes the
regex, the store's model field, and the show-args threading.

Generated-By: PostHog Code
Task-Id: 1039ea23-9930-44e2-9888-b05cf8b129ec

Author: adboio

packages/core/src/billing/usageLimitContent.test.ts

@@ -2,26 +2,15 @@ import { describe, expect, it } from "vitest";
 import { usageLimitContent } from "./usageLimitContent";
 
 describe("usageLimitContent", () => {
-  it("names the gated model and offers a payment method", () => {
+  it("offers a payment method for the model gate", () => {
     const content = usageLimitContent({
       cause: "model_gate",
-      model: "Claude Opus 4.8",
       resetLabel: null,
       billed: false,
     });
     expect(content.title).toBe("Unlock premium models");
-    expect(content.description).toContain("Claude Opus 4.8 isn't");
-    expect(content.actionLabel).toBe("Add payment method");
-  });
-
-  it("falls back to generic wording when the gated model is unknown", () => {
-    const content = usageLimitContent({
-      cause: "model_gate",
-      model: null,
-      resetLabel: null,
-      billed: undefined,
-    });
     expect(content.description).toContain("This model isn't");
+    expect(content.actionLabel).toBe("Add payment method");
   });
 
   it.each([
@@ -36,7 +25,6 @@ describe("usageLimitContent", () => {
     (billed, title, actionLabel) => {
       const content = usageLimitContent({
         cause: "org_limit",
-        model: null,
         resetLabel: null,
         billed,
       });
@@ -48,7 +36,6 @@ describe("usageLimitContent", () => {
   it("renders generic copy without a billing CTA when the cause is unknown", () => {
     const content = usageLimitContent({
       cause: null,
-      model: null,
       resetLabel: "Resets in 2h",
       billed: true,
     });

packages/core/src/billing/usageLimitContent.ts

@@ -10,17 +10,17 @@ export interface UsageLimitContent {
 
 export function usageLimitContent(args: {
   cause: GatewayLimitCause | null;
-  model: string | null;
   resetLabel: string | null;
   /** usage.code_usage_billed — absent means unknown, not free. */
   billed: boolean | undefined;
 }): UsageLimitContent {
-  const { cause, model, resetLabel, billed } = args;
+  const { cause, resetLabel, billed } = args;
 
   if (cause === "model_gate") {
     return {
       title: "Unlock premium models",
-      description: `${model ? `${model} isn't` : "This model isn't"} included in the free tier. Add a payment method to your organization to unlock all models — you only pay for what you use. You can keep working now by switching to an included model.`,
+      description:
+        "This model isn't included in the free tier. Add a payment method to your organization to unlock all models — you only pay for what you use. You can keep working now by switching to an included model.",
       actionLabel: "Add payment method",
       dismissLabel: "Not now",
     };

packages/core/src/sessions/sessionService.ts

@@ -16,7 +16,6 @@ import {
   type CloudRegion,
   classifyGatewayLimitError,
   type ExecutionMode,
-  extractGatedModel,
   flattenSelectOptions,
   getBackoffDelay,
   getCloudUrlFromRegion,
@@ -2730,17 +2729,7 @@ export class SessionService {
           isPromptPending: false,
           promptStartedAt: null,
         });
-        this.d.usageLimit.show(
-          limitCause === "model_gate"
-            ? {
-                cause: limitCause,
-                model:
-                  extractGatedModel(errorMessage, errorDetails) ?? undefined,
-              }
-            : limitCause
-              ? { cause: limitCause }
-              : undefined,
-        );
+        this.d.usageLimit.show(limitCause ? { cause: limitCause } : undefined);
         return { stopReason: "rate_limited" };
       }
 

packages/shared/src/errors.test.ts

@@ -1,7 +1,6 @@
 import { describe, expect, it } from "vitest";
 import {
   classifyGatewayLimitError,
-  extractGatedModel,
   getErrorMessage,
   isAuthError,
   isFatalSessionError,
@@ -137,26 +136,6 @@ describe("classifyGatewayLimitError", () => {
   });
 });
 
-describe("extractGatedModel", () => {
-  it("pulls the model id out of the gate message", () => {
-    expect(
-      extractGatedModel(
-        "Model 'claude-opus-4-8' needs a paid PostHog plan. Models available on the free tier: @cf/zai-org/glm-5.2.",
-      ),
-    ).toBe("claude-opus-4-8");
-  });
-
-  it("falls back to the details and returns null when absent", () => {
-    expect(
-      extractGatedModel(
-        "Internal error",
-        "Model 'gpt-5.5' needs a paid PostHog plan.",
-      ),
-    ).toBe("gpt-5.5");
-    expect(extractGatedModel("no model here")).toBeNull();
-  });
-});
-
 describe("isFatalSessionError", () => {
   it.each([
     "internal error",

packages/shared/src/errors.ts

@@ -141,20 +141,6 @@ export function isRateLimitError(
   );
 }
 
-const GATED_MODEL_REGEX = /Model '([^']+)' needs a paid PostHog plan/i;
-
-/** The model id a free-tier model-gate 403 names, when present. */
-export function extractGatedModel(
-  errorMessage: string,
-  errorDetails?: string,
-): string | null {
-  return (
-    errorMessage.match(GATED_MODEL_REGEX)?.[1] ??
-    errorDetails?.match(GATED_MODEL_REGEX)?.[1] ??
-    null
-  );
-}
-
 export function classifyGatewayLimitError(
   errorMessage: string,
   errorDetails?: string,

packages/shared/src/index.ts

@@ -73,7 +73,6 @@ export type { SignalReportPriority, Task } from "./domain-types";
 export * from "./enrichment";
 export {
   classifyGatewayLimitError,
-  extractGatedModel,
   type GatewayLimitCause,
   getErrorMessage,
   isAuthError,

packages/ui/src/features/billing/UsageLimitModal.tsx

@@ -15,7 +15,6 @@ export function UsageLimitModal() {
   const isOpen = useUsageLimitStore((s) => s.isOpen);
   const resetAt = useUsageLimitStore((s) => s.resetAt);
   const cause = useUsageLimitStore((s) => s.cause);
-  const model = useUsageLimitStore((s) => s.model);
   const hide = useUsageLimitStore((s) => s.hide);
   const cloudRegion = useAuthStateValue((state) => state.cloudRegion);
   // code_usage_billed picks the org_limit copy variant.
@@ -32,7 +31,6 @@ export function UsageLimitModal() {
 
   const content = usageLimitContent({
     cause,
-    model,
     resetLabel: resetAt ? formatResetTime(resetAt) : null,
     billed: usage?.code_usage_billed,
   });

packages/ui/src/features/billing/usageLimitStore.test.ts

@@ -7,7 +7,6 @@ describe("usageLimitStore", () => {
       isOpen: false,
       resetAt: null,
       cause: null,
-      model: null,
     });
   });
 
@@ -22,20 +21,17 @@ describe("usageLimitStore", () => {
     expect(state.isOpen).toBe(true);
     expect(state.resetAt).toBeNull();
     expect(state.cause).toBeNull();
-    expect(state.model).toBeNull();
   });
 
   it("show stores the denial context when provided", () => {
     useUsageLimitStore.getState().show({
       resetAt: "2026-01-02T03:04:05Z",
       cause: "model_gate",
-      model: "claude-opus-4-8",
     });
     const state = useUsageLimitStore.getState();
     expect(state.isOpen).toBe(true);
     expect(state.resetAt).toBe("2026-01-02T03:04:05Z");
     expect(state.cause).toBe("model_gate");
-    expect(state.model).toBe("claude-opus-4-8");
   });
 
   it("hide closes the modal", () => {

packages/ui/src/features/billing/usageLimitStore.ts

@@ -5,15 +5,12 @@ export interface UsageLimitShowArgs {
   resetAt?: string;
   /** Which gateway denial tripped; unset renders the generic copy. */
   cause?: GatewayLimitCause;
-  /** The model the gate blocked, when known. */
-  model?: string;
 }
 
 interface UsageLimitState {
   isOpen: boolean;
   resetAt: string | null;
   cause: GatewayLimitCause | null;
-  model: string | null;
 }
 
 interface UsageLimitActions {
@@ -27,14 +24,12 @@ export const useUsageLimitStore = create<UsageLimitStore>()((set) => ({
   isOpen: false,
   resetAt: null,
   cause: null,
-  model: null,
 
   show: (args) =>
     set({
       isOpen: true,
       resetAt: args?.resetAt ?? null,
       cause: args?.cause ?? null,
-      model: args?.model ?? null,
     }),
   hide: () => set({ isOpen: false }),
 }));