fix(desktop): preserve named custom model providers

[ivankhokholkov]

Summary

• preserve named custom provider slugs such as custom:polza.ai in the Desktop model assignment API
• prevent vendor-prefixed model IDs from incorrectly triggering the OpenRouter fallback
• add a regression test covering the Desktop selection flow

Reproduction

1. Configure a named OpenAI-compatible custom provider, for example Polza.ai.
2. In Desktop Settings > Model, select that provider and a vendor-prefixed model such as deepseek/deepseek-v4-flash.
3. Click Apply.
4. Observe that model.provider is persisted as openrouter, so Gateway reports missing OpenRouter credentials.

Root cause

_normalize_main_model_assignment treated every provider absent from the built-in registry as a possible model vendor. Named custom provider slugs are user-defined and therefore absent from that registry, so models containing / caused the provider to be rewritten to the current aggregator or OpenRouter.

Verification

• pytest tests/hermes_cli/test_web_server.py -q: 274 passed
• ruff check hermes_cli/web_server.py tests/hermes_cli/test_web_server.py: passed
• npm --prefix apps/desktop run build: passed
• runtime resolution verified for custom:polza.ai with its configured base URL and credential pool

[alt-glitch]

Duplicate of #45069 — identical fix (preserve custom: provider slugs in _normalize_main_model_assignment, same file hermes_cli/web_server.py); #45069 was opened ~9 min earlier.

[RAVnastasia]

Thanks for flagging this. Confirmed that #45069 addresses the same root cause. This PR also includes a focused regression test for custom:polza.ai with a vendor-prefixed model ID, in case that test is useful to cherry-pick. Closing in favor of #45069.

[ivankhokholkov]

Thank you for looking into this. I’m preparing a YouTube video about using custom LLM providers with Hermes Desktop, scheduled for release around June 15. The current bug makes this workflow unusable for viewers because Hermes saves the selected custom provider as OpenRouter and the Gateway fails. I’ve confirmed that the provider API and credentials work correctly, and the proposed fix resolves the issue locally. If possible, could you please prioritize this fix for the next Desktop update? It would help me provide viewers with accurate setup instructions instead of a terminal workaround. Thank you! пт, 12 июн. 2026 г. в 20:04, Siddharth Balyan ***@***.***>:

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*alt-glitch* left a comment (NousResearch/hermes-agent#45075) <#45075 (comment)> Duplicate of #45069 <#45069> — identical fix (preserve custom: provider slugs in _normalize_main_model_assignment, same file hermes_cli/web_server.py); #45069 <#45069> was opened ~9 min earlier. — Reply to this email directly, view it on GitHub <#45075?email_source=notifications&email_token=BVHP3DATNQGH7XMUCWYP7BT47QZ2RA5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTINRZGM2DINZWGUZKM4TFMFZW63VGMF2XI2DPOKSWK5TFNZ2KYZTPN52GK4S7MNWGSY3L#issuecomment-4693447652>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/BVHP3DFNKPWFMUXOOOVTAFL47QZ2RAVCNFSNUABGKJSXA33TNF2G64TZHMYTAMRUGU2TIMRWG45US43TOVSTWNBWGUYTANZSGU2TNILWAI> . You are receiving this because you authored the thread.Message ID: ***@***.***>