fix(opencode): extract statusCode from error variants for 5xx retry

Some OpenAI-compatible providers throw native Error subclasses or plain
objects instead of ai-sdk's APICallError. These fell through to
NamedError.Unknown and were not retried, even on 5xx status codes.

Extract statusCode from common error shapes (Error.status,
Error.statusCode, Error.response.status, JSON-encoded message) and
treat 5xx as retryable in both `instanceof Error` and plain object
fallback branches.

Closes #19203

Author: okuyam2y

packages/opencode/src/session/message-v2.ts

@@ -24,6 +24,14 @@ interface FetchDecompressionError extends Error {
   path: string
 }
 
+/** Common shapes for non-APICallError provider errors carrying HTTP status */
+interface ErrorWithStatus {
+  status?: number
+  statusCode?: number
+  response?: { status?: number; statusCode?: number }
+  message?: string
+}
+
 export namespace MessageV2 {
   export function isMedia(mime: string) {
     return mime.startsWith("image/") || mime === "application/pdf"
@@ -1022,8 +1030,33 @@ export namespace MessageV2 {
           },
           { cause: e },
         ).toObject()
-      case e instanceof Error:
+      case e instanceof Error: {
+        // Non-APICallError with HTTP status - treat 5xx as retryable.
+        const typed = e as Error & ErrorWithStatus
+        const code =
+          typed.status ?? typed.statusCode ??
+          typed.response?.status ?? typed.response?.statusCode
+        if (typeof code === "number" && code >= 500)
+          return new MessageV2.APIError(
+            { message: e.message, statusCode: code, isRetryable: true },
+            { cause: e },
+          ).toObject()
+        // Fallback: status may be embedded in a JSON error message.
+        try {
+          const obj = JSON.parse(e.message) as ErrorWithStatus
+          const status =
+            obj?.status ?? obj?.statusCode ??
+            obj?.response?.status ?? obj?.response?.statusCode
+          if (typeof status === "number" && status >= 500) {
+            const msg = typeof obj?.message === "string" ? obj.message : e.message
+            return new MessageV2.APIError(
+              { message: msg, statusCode: status, isRetryable: true },
+              { cause: e },
+            ).toObject()
+          }
+        } catch {}
         return new NamedError.Unknown({ message: errorMessage(e) }, { cause: e }).toObject()
+      }
       default:
         try {
           const parsed = ProviderError.parseStreamError(e)
@@ -1049,6 +1082,20 @@ export namespace MessageV2 {
             ).toObject()
           }
         } catch {}
+        // Plain-object 5xx - treat as retryable.
+        if (typeof e === "object" && e !== null) {
+          const typed = e as ErrorWithStatus
+          const code = typed.status ?? typed.statusCode ?? typed.response?.status ?? typed.response?.statusCode
+          if (typeof code === "number" && code >= 500)
+            return new MessageV2.APIError(
+              {
+                message: typeof typed.message === "string" ? typed.message : JSON.stringify(e),
+                statusCode: code,
+                isRetryable: true,
+              },
+              { cause: e },
+            ).toObject()
+        }
         return new NamedError.Unknown({ message: JSON.stringify(e) }, { cause: e }).toObject()
     }
   }

packages/opencode/test/session/message-v2.test.ts

@@ -1003,6 +1003,159 @@ describe("session.message-v2.fromError", () => {
     })
   })
 
+  test("retries 5xx Error with statusCode property", () => {
+    const err = Object.assign(new Error("Internal Server Error"), { statusCode: 502 })
+
+    const result = MessageV2.fromError(err, { providerID })
+
+    expect(MessageV2.APIError.isInstance(result)).toBe(true)
+    expect((result as MessageV2.APIError).data.isRetryable).toBe(true)
+    expect((result as MessageV2.APIError).data.statusCode).toBe(502)
+  })
+
+  test("retries 5xx Error with status property", () => {
+    const err = Object.assign(new Error("Bad Gateway"), { status: 503 })
+
+    const result = MessageV2.fromError(err, { providerID })
+
+    expect(MessageV2.APIError.isInstance(result)).toBe(true)
+    expect((result as MessageV2.APIError).data.isRetryable).toBe(true)
+    expect((result as MessageV2.APIError).data.statusCode).toBe(503)
+  })
+
+  test("retries 5xx Error with response.status", () => {
+    const err = Object.assign(new Error("Gateway Timeout"), { response: { status: 504 } })
+
+    const result = MessageV2.fromError(err, { providerID })
+
+    expect(MessageV2.APIError.isInstance(result)).toBe(true)
+    expect((result as MessageV2.APIError).data.isRetryable).toBe(true)
+    expect((result as MessageV2.APIError).data.statusCode).toBe(504)
+  })
+
+  test("retries 5xx Error with response.statusCode", () => {
+    const err = Object.assign(new Error("Bad Gateway"), { response: { statusCode: 502 } })
+
+    const result = MessageV2.fromError(err, { providerID })
+
+    expect(MessageV2.APIError.isInstance(result)).toBe(true)
+    expect((result as MessageV2.APIError).data.isRetryable).toBe(true)
+    expect((result as MessageV2.APIError).data.statusCode).toBe(502)
+  })
+
+  test("retries 5xx from JSON-encoded Error message with status property", () => {
+    const err = new Error(JSON.stringify({ status: 500, message: "server error" }))
+
+    const result = MessageV2.fromError(err, { providerID })
+
+    expect(MessageV2.APIError.isInstance(result)).toBe(true)
+    expect((result as MessageV2.APIError).data.isRetryable).toBe(true)
+    expect((result as MessageV2.APIError).data.statusCode).toBe(500)
+  })
+
+  test("retries 5xx from JSON-encoded Error message and extracts inner message", () => {
+    const err = new Error(JSON.stringify({ statusCode: 500, message: "server error" }))
+
+    const result = MessageV2.fromError(err, { providerID })
+
+    expect(MessageV2.APIError.isInstance(result)).toBe(true)
+    expect((result as MessageV2.APIError).data.isRetryable).toBe(true)
+    expect((result as MessageV2.APIError).data.statusCode).toBe(500)
+    expect((result as MessageV2.APIError).data.message).toBe("server error")
+  })
+
+  test("retries 5xx from JSON-encoded Error message with nested response.statusCode", () => {
+    const err = new Error(JSON.stringify({ response: { statusCode: 503 }, message: "upstream" }))
+
+    const result = MessageV2.fromError(err, { providerID })
+
+    expect(MessageV2.APIError.isInstance(result)).toBe(true)
+    expect((result as MessageV2.APIError).data.isRetryable).toBe(true)
+    expect((result as MessageV2.APIError).data.statusCode).toBe(503)
+    expect((result as MessageV2.APIError).data.message).toBe("upstream")
+  })
+
+  test("retries 5xx from JSON-encoded Error message with nested response.status", () => {
+    const err = new Error(JSON.stringify({ response: { status: 502 }, message: "bad gw" }))
+
+    const result = MessageV2.fromError(err, { providerID })
+
+    expect(MessageV2.APIError.isInstance(result)).toBe(true)
+    expect((result as MessageV2.APIError).data.isRetryable).toBe(true)
+    expect((result as MessageV2.APIError).data.statusCode).toBe(502)
+  })
+
+  test("does not retry 4xx from JSON-encoded Error message", () => {
+    const err = new Error(JSON.stringify({ statusCode: 422, message: "invalid request" }))
+
+    const result = MessageV2.fromError(err, { providerID })
+
+    expect(result.name).toBe("UnknownError")
+  })
+
+  test("retries 5xx from plain object with status property", () => {
+    const err = { status: 500, message: "Internal Server Error" }
+
+    const result = MessageV2.fromError(err, { providerID })
+
+    expect(MessageV2.APIError.isInstance(result)).toBe(true)
+    expect((result as MessageV2.APIError).data.isRetryable).toBe(true)
+    expect((result as MessageV2.APIError).data.statusCode).toBe(500)
+  })
+
+  test("retries 5xx from plain object with statusCode", () => {
+    const err = { statusCode: 502, message: "Bad Gateway" }
+
+    const result = MessageV2.fromError(err, { providerID })
+
+    expect(MessageV2.APIError.isInstance(result)).toBe(true)
+    expect((result as MessageV2.APIError).data.isRetryable).toBe(true)
+    expect((result as MessageV2.APIError).data.statusCode).toBe(502)
+  })
+
+  test("retries 5xx from plain object with response.status", () => {
+    const err = { response: { status: 500 }, message: "fail" }
+
+    const result = MessageV2.fromError(err, { providerID })
+
+    expect(MessageV2.APIError.isInstance(result)).toBe(true)
+    expect((result as MessageV2.APIError).data.isRetryable).toBe(true)
+  })
+
+  test("retries 5xx from plain object with response.statusCode", () => {
+    const err = { response: { statusCode: 503 }, message: "unavailable" }
+
+    const result = MessageV2.fromError(err, { providerID })
+
+    expect(MessageV2.APIError.isInstance(result)).toBe(true)
+    expect((result as MessageV2.APIError).data.isRetryable).toBe(true)
+    expect((result as MessageV2.APIError).data.statusCode).toBe(503)
+  })
+
+  test("does not retry 4xx from plain object", () => {
+    const err = { statusCode: 404, message: "Not Found" }
+
+    const result = MessageV2.fromError(err, { providerID })
+
+    expect(result.name).toBe("UnknownError")
+  })
+
+  test("does not retry 4xx Error", () => {
+    const err = Object.assign(new Error("Not Found"), { statusCode: 404 })
+
+    const result = MessageV2.fromError(err, { providerID })
+
+    expect(result.name).toBe("UnknownError")
+  })
+
+  test("does not retry Error without statusCode", () => {
+    const err = new Error("something went wrong")
+
+    const result = MessageV2.fromError(err, { providerID })
+
+    expect(result.name).toBe("UnknownError")
+  })
+
   test("classifies ZlibError from fetch as retryable APIError", () => {
     const zlibError = new Error(
       'ZlibError fetching "https://opencode.cloudflare.dev/anthropic/messages". For more information, pass `verbose: true` in the second argument to fetch()',