[Bug]: parallelToolCalls=false only sends parallel_tool_calls:false for the NVIDIA NIM baseUrl; ignored for all other opted-out providers

Client or integration

Codex App

Area

Proxy and routing

Summary

provider.parallelToolCalls === false only actually sends parallel_tool_calls: false on the wire when the provider's baseUrl is exactly https://integrate.api.nvidia.com/v1. Every other OpenAI-compatible provider that sets parallelToolCalls: false in its config silently gets no wire bit, so upstreams that default to parallel tool calls keep emitting multiple concurrent tool calls in one streamed turn.

For Kimi-family and some GLM-family gateways, the streamed multi-call turn then can't be assembled cleanly into Responses-shaped function-call events, and Codex fails the turn (previously surfaced as upstream response contained invalid tool calls; after the 2.14 null-tool_calls hardening, still a broken/incomplete multi-tool turn). Setting parallelToolCalls: false — which the config schema advertises as the way to opt out — has no effect for these providers.

What I expected

parallelToolCalls: false should pin parallel_tool_calls: false on the request for any opted-out provider, not just the hardcoded NVIDIA NIM host. The config field reads as provider-agnostic; the enforcement is host-specific.

Evidence (code path)

src/adapters/openai-chat.ts, request builder:

if (provider.parallelToolCalls === false) {
  // NIM documents the Boolean defaulting to false and kimi rejects true; pin the
  // wire bit so Codex cannot opt in via request.options. Other opted-out providers
  // omit the field so strict OpenAI-compatible hosts never see an unsupported knob.
  if (provider.baseUrl === "https://integrate.api.nvidia.com/v1") {
    body.parallel_tool_calls = false;
  }
} else if (provider.parallelToolCalls === true) {
  body.parallel_tool_calls = parsed.options.parallelToolCalls !== false;
}

The comment's intent ("Other opted-out providers omit the field so strict OpenAI-compatible hosts never see an unsupported knob") is reasonable as a default, but it makes parallelToolCalls: false a no-op for every non-NVIDIA gateway that genuinely needs the wire bit. There's no per-provider way to force it short of matching the NVIDIA URL.

Reproduction

Configure an OpenAI-compatible openai-chat provider (e.g. a Kimi-K3 gateway) with "parallelToolCalls": false.
Send a Codex turn that naturally invites two independent tool calls (e.g. "read file A and list dir B").
Observe the upstream returns 2 parallel tool_calls chunks in the same choice; parallel_tool_calls: false was never sent.
As a control, send the exact same upstream body with parallel_tool_calls: false added manually — the upstream then returns a single tool call.

Proposal (either is fine)

Send body.parallel_tool_calls = false whenever provider.parallelToolCalls === false, regardless of baseUrl; or
Keep the NVIDIA-only default but add an explicit opt-in (e.g. provider.forceParallelToolCallsFalse: true) so gateways that reject/ignore parallel calls can pin the bit without a URL match.

Version

opencodex 2.14.2 (ocx --version); running local service confirmed via GET /healthz.

Operating system

macOS 26.5.1 (25F80)

Provider and model

OpenAI-compatible openai-chat routed providers (Kimi-K3, GLM-5.2 families) on a self-hosted gateway. Not NVIDIA NIM. Reproducible with any openai-chat provider whose upstream emits parallel tool calls by default.

🔗 Related PRs

#304 - fix(kiro): restore hardening and complete text turns [open]
#616 - fix: preserve hosted image tool preferences [open]
#746 - fix(providers): route GitHub Copilot Responses-only models off chat completions [open]
#1317 - feat(providers): add Featherless preset [merged]
#1531 - fix(openai-chat): refuse to emit an unnamed streamed tool call [merged]

📝 Issue Planner

_{Check the box below or use the @coderabbitai plan command to generate an implementation plan and prompts that you can use with your favorite coding assistant.}

Create Plan

🧪 Issue enrichment is currently in open beta.

To disable automatic issue enrichment, add the following to your .coderabbit.yaml:

issue_enrichment:
  auto_enrich:
    enabled: false

💬 Have feedback or questions? Drop into our discord!

Note for triage: this is distinct from #1531. #1531 changed how an already-produced unnamed/invalid tool call is terminated (fail closed with a loud error instead of emitting a nameless call). This issue is upstream of that: it is about the parallel tool calls being requested in the first place.

provider.parallelToolCalls === false is documented as the opt-out, but the wire bit parallel_tool_calls: false is only actually sent when provider.baseUrl === "https://integrate.api.nvidia.com/v1". For every other opted-out OpenAI-compatible provider (e.g. a self-hosted Kimi/GLM gateway) the field is silently omitted, so the upstream keeps emitting multiple concurrent tool calls in one streamed turn. #1531's hardening then makes that turn fail more cleanly, but the turn still fails — the fix here is to stop requesting parallel calls at all for opted-out providers, not to clean up after them.

fix(openai-chat): let opted-out providers pin parallel_tool_calls:false

I'm working on honoring provider.parallelToolCalls === false on the openai-chat wire for every opted-out provider, not only the NVIDIA NIM baseUrl, and will open a draft PR shortly. Distinct from #1531: this is about requesting serialized tool calls, not fail-closing already-invalid streamed calls.

Confirmed fixed on dev. PR #1662 merged as e480ce74803e1acd06d0a1b656101713051ad911 and adds the explicit pinParallelToolCallsFalse opt-in while preserving the existing omit-by-default behavior for strict OpenAI-compatible hosts. The focused regression coverage verifies that parallel_tool_calls: false is emitted only when both parallelToolCalls: false and the new pin are set. Closing as fixed in dev; it will reach users with the next maintainer promotion/release.

Thanks — I see #1662 already landed proposal 2 (pinParallelToolCallsFalse) and this is closed as fixed on dev. I will not open a conflicting PR that would pin parallel_tool_calls: false for every parallelToolCalls: false provider.

fix(openai-chat): let opted-out providers pin parallel_tool_calls:false

Navigation Menu

Repository navigation

[Bug]: parallelToolCalls=false only sends parallel_tool_calls:false for the NVIDIA NIM baseUrl; ignored for all other opted-out providers #1650

Client or integration

Area

Summary

What I expected

Evidence (code path)

Reproduction

Proposal (either is fine)

Version

Operating system

Provider and model

Metadata

Assignees

Labels

Projects

Milestone

Relationships

Development

[Bug]: parallelToolCalls=false only sends parallel_tool_calls:false for the NVIDIA NIM baseUrl; ignored for all other opted-out providers #1650

Description

Client or integration

Area

Summary

What I expected

Evidence (code path)

Reproduction

Proposal (either is fine)

Version

Operating system

Provider and model

Activity

coderabbitai commented on Aug 14, 2026

tone-leh commented on Aug 14, 2026

LeoWang331 commented on Aug 14, 2026

Ingwannu commented on Aug 14, 2026

LeoWang331 commented on Aug 14, 2026

Metadata

Metadata

Assignees

Labels

Projects

Milestone

Relationships

Development

Issue actions