From 99b42dd9c69bf11ca7bc27e8e148d76ddbe7c6b4 Mon Sep 17 00:00:00 2001
From: Alexandr Suhinin <alexandr.suhinin@jetbrains.com>
Date: Thu, 7 May 2026 13:09:28 +0300
Subject: [PATCH] fix: explicitly pass model provider on session resume

---
 src/CodexAcpClient.ts | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/CodexAcpClient.ts b/src/CodexAcpClient.ts
index f085481..182a028 100644
--- a/src/CodexAcpClient.ts
+++ b/src/CodexAcpClient.ts
@@ -210,7 +210,7 @@ export class CodexAcpClient {
             cwd: request.cwd,
             developerInstructions: null,
             model: null,
-            modelProvider: this.getModelProvider(),
+            modelProvider: this.getResumeModelProvider(),
             personality: null,
             threadId: request.sessionId,
         });
@@ -232,7 +232,7 @@ export class CodexAcpClient {
             cwd: request.cwd,
             developerInstructions: null,
             model: null,
-            modelProvider: this.getModelProvider(),
+            modelProvider: this.getResumeModelProvider(),
             personality: null,
             threadId: request.sessionId,
         });
@@ -304,6 +304,12 @@ export class CodexAcpClient {
         return this.gatewayConfig?.modelProvider ?? this.modelProvider;
     }
 
+    private getResumeModelProvider(): string {
+        // Passing `null` forces codex to use the persisted provider for resumed session instead of default one
+        // Explicit fallback to "openai" fixes error `Model provider not found` at least for ChatGPT authentication
+        return this.getModelProvider() ?? "openai";
+    }
+
     private async refreshSkills(cwd: string, meta?: Record<string, unknown> | null): Promise<void> {
         if (!cwd) {
             return;