fix: preserve user-defined providers when assigning model via GUI/API

[mmchuangyt-ai]

Summary

_normalize_main_model_assignment() in hermes_cli/web_server.py had a blind spot: when a user-defined provider (configured via config.yaml -> providers:) was used to assign a model through the desktop GUI or /api/model/set, the function checked only built-in _KNOWN_PROVIDER_NAMES and _AGGREGATOR_PROVIDERS. Custom providers like open.cherryin.net matched neither, so the code unconditionally fell back to openrouter, silently overwriting the user configured provider.

Root cause

https://github.com/NousResearch/hermes-agent/blob/30e947e0a/hermes_cli/web_server.py#L998-L1016

The fallback logic at line 998 only handled two cases:

• Provider is in _KNOWN_PROVIDER_NAMES (built-in) → proceed to model normalization
• Provider is an aggregator (_AGGREGATOR_PROVIDERS) → keep current provider
• Everything else → fallback to openrouter ← the bug

Fix

Before falling back to openrouter, check whether the provider slug exists in config.yaml -> providers: (the user-defined provider registry). If it does, return immediately — custom provider namespaces are opaque to the built-in normalizer and should be preserved verbatim.

This aligns the HTTP API behavior with what the CLI hermes model picker already does (which skips _normalize_main_model_assignment entirely for user-defined providers).

Test plan

1. Set up a custom provider in config.yaml -> providers: (e.g. open.cherryin.net with its own api endpoint)
2. Open Desktop GUI → Model Settings → Select a model under the custom provider → Apply
3. Before fix: config.yaml -> model.provider is overwritten to openrouter
4. After fix: config.yaml -> model.provider correctly stays as the custom provider slug

Related

Fixes an issue where Desktop GUI model selection silently breaks custom providers.

[teknium1]

This PR’s reported dashboard/API provider-rewrite behavior is already fixed on current main. This is an automated hermes-sweeper review.

• Commit 9a15fad0d6c370ba09bf87af92144f46ccd2bc4a (fix(web): preserve declared providers in model writes (#63058)) added the consolidated fix.
• hermes_cli/web_server.py:1063-1082 resolves configured providers: and legacy custom_providers: before the unknown-vendor → OpenRouter fallback.
• hermes_cli/web_server.py:5819 applies that normalization in POST /api/model/set before persisting configuration.
• tests/hermes_cli/test_main_model_custom_provider_normalization.py:13-40 covers configured provider preservation, custom-provider canonicalization, and the genuine unknown-vendor fallback.

The later consolidated implementation also covers the related #60337 path referenced in the timeline, so this focused patch is redundant.