hermes - 💡(How to fix) Fix [Bug]: custom GPT-5.4 provider via gateway hits Responses API 400 "Invalid 'input[n].name': empty string" even after /reset and update [1 participants]

Bug Description

When Hermes Agent is used through the gateway with a custom provider and model gpt-5.4, normal user messages can fail with a Responses API 400:

HTTP 400: Invalid 'input[n].name': empty string

This still reproduces after:

• running hermes update
• confirmed gateway service restart
• running /reset multiple times

This no longer looks like a stale session problem. The error index changes between input[3] and input[4], which suggests Hermes is generating or replaying a malformed Responses input item containing an empty function_call.name.

I first noticed fragmented / logically disconnected replies in Weixin, but the current blocking issue is broader: after reset, even a simple plain-text message can fail immediately.

Related upstream context: #10473, #10548, #8133, #11179, #10175, #11001.

Steps to Reproduce

1. Configure Hermes with a custom provider / relay
2. Select model gpt-5.4
3. Use the messaging gateway
4. Run /update and confirm the gateway restart is reported
5. Run /reset
6. Send a plain text message such as 当前hermes版本是多少
7. Hermes returns a 400 error instead of answering

Expected Behavior

A fresh session after /reset should accept a normal user message and return a normal answer.

Actual Behavior

Hermes returns:

Non-retryable error (HTTP 400): HTTP 400: Invalid 'input[3].name': empty string. Expected a string with minimum length 1, but got an empty string instead.

Sometimes the index is input[4] instead of input[3]. The fallback path also fails with the same error.

Affected Component

Setup / Installation, Tools (terminal, file ops, web, code execution, etc.), Configuration (config.yaml, .env, hermes setup)

Messaging Platform (if gateway-related)

No response

Debug Report

Used `hermes debug share --local` because I am filing from a local environment.

Summary:
- version: 0.8.0 (2026.4.8) [964ef681]
- os: Darwin 24.6.0 arm64
- python: 3.11.6
- openai_sdk: 2.31.0
- profile: default
- model: gpt-5.4
- provider: custom
- terminal: local

Relevant local dump shows the active model/provider are indeed `gpt-5.4` + `custom`.

Operating System

macOS 15.6 / Darwin 24.6.0

Python Version

3.11.6

Hermes Version

0.8.0 (2026.4.8) [964ef681]

Additional Logs / Traceback (optional)

Observed user-facing error:


Non-retryable error (HTTP 400): HTTP 400: Invalid 'input[4].name': empty string. Expected a string with minimum length 1, but got an empty string instead.

Error code: 400 - {'error': {'message': "Invalid 'input[4].name': empty string. Expected a string with minimum length 1, but got an empty string instead.", 'type': 'invalid_request_error', 'param': 'input[4].name', 'code': 'empty_string'}}

Non-retryable error (HTTP 400) — trying fallback...


Another repro after `/reset`:


❌ Non-retryable error (HTTP 400): HTTP 400: Invalid 'input[3].name': empty string. Expected a string with minimum length 1, but got an empty string instead.

Root Cause Analysis (optional)

Likely related to Hermes forcing GPT-5.x models onto the Responses API path for custom providers, and then building or replaying a malformed Responses input item where a function_call has an empty name.

Given that the issue still reproduces immediately after /reset and after a confirmed hermes update + gateway restart, this appears to be a Hermes/runtime compatibility bug rather than only a stale session artifact.

Proposed Fix (optional)

Two likely directions:

1. Do not force custom GPT-5 providers onto the Responses path when the provider does not fully match OpenAI Responses semantics
2. Add stricter validation before sending Responses input, and drop malformed function_call items whose name is empty

Are you willing to submit a PR for this?

• I'd like to fix this myself and submit a PR