diff --git a/apps/server/src/provider/ClaudeProvider.ts b/apps/server/src/provider/ClaudeProvider.ts
index 97512d3d621f0..d4df602000144 100644
--- a/apps/server/src/provider/ClaudeProvider.ts
+++ b/apps/server/src/provider/ClaudeProvider.ts
@@ -244,7 +244,7 @@ export type ClaudeCapabilitiesProbe = {
   readonly apiProvider: string | undefined;
   readonly slashCommands: ReadonlyArray<ServerProviderSlashCommand>;
   readonly models?: ReadonlyArray<ClaudeModelInfo>;
-  /** Undefined means get_usage failed; absent windows on success mean no subscription windows, as with API keys. */
+  /** Omitted when usage collection is skipped or fails; `rate_limits.error` also means failure. Absent windows on success mean no subscription windows. */
   readonly usage?: Pick<SDKControlGetUsageResponse, "rate_limits_available" | "rate_limits">;
   readonly usageCheckedAt?: string;
 };
diff --git a/apps/server/src/provider/claudeUsageLimits.test.ts b/apps/server/src/provider/claudeUsageLimits.test.ts
index f20d8b0543636..92ad088a17731 100644
--- a/apps/server/src/provider/claudeUsageLimits.test.ts
+++ b/apps/server/src/provider/claudeUsageLimits.test.ts
@@ -107,6 +107,25 @@ describe("claudeUsageResponseToLimits", () => {
     ]);
   });
 
+  it("treats a refused usage read as a failed probe, not as zero windows", () => {
+    expect(
+      claudeUsageResponseToLimits({
+        checkedAt,
+        response: {
+          rate_limits_available: true,
+          rate_limits: {
+            ...({
+              error: { type: "rate_limit_error", message: "Rate limited. Please try again later." },
+            } as object),
+          },
+        },
+      }),
+    ).toEqual({
+      names: noNames,
+      limits: { checkedAt, windows: [], unavailable: { reason: "probeFailed" } },
+    });
+  });
+
   const enterpriseResponse = {
     rate_limits_available: true,
     rate_limits: {
diff --git a/apps/server/src/provider/claudeUsageLimits.ts b/apps/server/src/provider/claudeUsageLimits.ts
index d0acf43bb4968..6e029ec1c1254 100644
--- a/apps/server/src/provider/claudeUsageLimits.ts
+++ b/apps/server/src/provider/claudeUsageLimits.ts
@@ -177,7 +177,8 @@ export function claudeUsageResponseToLimits(input: {
   readonly checkedAt: string;
 }): { readonly limits: ServerProviderUsageLimits; readonly names: ClaudeScopedLimitNames } {
   const { response, checkedAt } = input;
-  if (!response.rate_limits_available || !response.rate_limits) {
+  // The SDK does not type it, but a refused usage read (e.g. HTTP 429) arrives as `rate_limits: { error }`.
+  if (!response.rate_limits_available || !response.rate_limits || "error" in response.rate_limits) {
     return {
       limits: makeUnavailableUsageLimits({
         checkedAt,