From 2cd0c8b515d83bc838b1df5089859cf28eb461f3 Mon Sep 17 00:00:00 2001
From: Peter Steinberger <steipete@gmail.com>
Date: Fri, 29 May 2026 08:05:05 -0400
Subject: [PATCH] fix(agents): centralize failover status parsing

---
 src/agents/failover-error.test.ts | 2 ++
 src/agents/failover-error.ts      | 5 +++--
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/agents/failover-error.test.ts b/src/agents/failover-error.test.ts
index 3ee83d7c877..854ef1eaafc 100644
--- a/src/agents/failover-error.test.ts
+++ b/src/agents/failover-error.test.ts
@@ -77,6 +77,8 @@ describe("failover-error", () => {
       }),
     ).toBe("billing");
     expect(resolveFailoverReasonFromError({ statusCode: "429" })).toBe("rate_limit");
+    expect(resolveFailoverReasonFromError({ statusCode: "+429" })).toBe("rate_limit");
+    expect(resolveFailoverReasonFromError({ statusCode: "0x1ad" })).toBeNull();
     expect(resolveFailoverReasonFromError({ status: 403 })).toBe("auth");
     expect(resolveFailoverReasonFromError({ status: 408 })).toBe("timeout");
     expect(resolveFailoverReasonFromError({ status: 410 })).toBe("timeout");
diff --git a/src/agents/failover-error.ts b/src/agents/failover-error.ts
index 6a1e5a95a93..66b31554a5d 100644
--- a/src/agents/failover-error.ts
+++ b/src/agents/failover-error.ts
@@ -1,4 +1,5 @@
 import { readErrorName } from "../infra/errors.js";
+import { parseStrictNonNegativeInteger } from "../shared/number-coercion.js";
 import {
   classifyFailoverSignal,
   inferSignalStatus,
@@ -132,8 +133,8 @@ function readDirectStatusCode(err: unknown): number | undefined {
   if (typeof candidate === "number") {
     return candidate;
   }
-  if (typeof candidate === "string" && /^\d+$/.test(candidate)) {
-    return Number(candidate);
+  if (typeof candidate === "string") {
+    return parseStrictNonNegativeInteger(candidate);
   }
   return undefined;
 }