[Bug]: OpenCode Go native Responses path leaks undeclared apply_patch and shows aborted #1699

Client or integration

Codex App

Area

Provider adapter

Summary

OpenCodex 2.17.0 can leak an undeclared top-level apply_patch function call through the native OpenAI Responses passthrough path when using OpenCode Go. Codex App then displays aborted, while the target file is unchanged.

Expected behavior: an undeclared routed tool should fail closed with an explicit compatibility error before reaching the Codex executor. The supported editing path should remain exec -> tools.apply_patch(...).

This is related to #1544, #1576, and #1623, but the relevant distinction is that this reproduction uses the openai-responses adapter path.

Reproduction

1. Start OpenCodex on port 10100.
2. Use exec -> tools.apply_patch(...) to create a temporary file containing v1.
3. Invoke top-level apply_patch with a patch changing v1 to v2.
4. Observe that Codex App displays aborted.
5. Check the file: it remains v1; no content or mtime change is observed.
6. Run the equivalent patch through exec -> tools.apply_patch(...):
   • an intentionally incorrect expected line returns a real apply_patch verification failed error;
   • the correct v1 -> v3 patch succeeds.

The request-visible tool catalog contained exec, wait, and request_user_input, but no top-level apply_patch schema. The session nevertheless received a function_call named apply_patch.

Version

OpenCodex 2.17.0

Operating system

macOS 27.0, Apple Silicon

Provider and model

Provider: opencode-go

Model: deepseek-v4-flash

At the time of reproduction, the provider default was openai-chat, but this model had an explicit openai-responses adapter override.

Logs or error output

Observed Codex result:

aborted

Session observations:

• top-level call was recorded as function_call(name=apply_patch);
• no corresponding custom_tool_call_output was emitted;
• the file was not modified;
• OpenCode Go usage records were HTTP 200;
• no upstream aborted, OpenCodex response.failed, approval denial, or sandbox denial was observed.

Screenshots and supporting files

No screenshots attached. Reproduction artifacts were written only under /tmp.

Redacted configuration

{
  "providers": {
    "opencode-go": {
      "adapter": "openai-chat",
      "baseUrl": "https://opencode.ai/zen/go/v1",
      "modelAdapters": {
        "deepseek-v4-flash": "openai-responses"
      }
    }
  }
}

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