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+# AI Model Chain — IT Pro Partner
+
+**Updated:** July 21, 2026
+**Gateways:** admin-ai (self-hosted LiteLLM), OpenRouter, DeepSeek, Google, xAI
+
+## Chain
+
+| # | Model | Provider | Key Status |
+|---|---|---|---|
+| Primary | GPT-5.5 | admin-ai | ✅ `sk-aEJ...` |
+| F1 | GPT-5.5 | OpenRouter | ✅ `sk-or-v1...` |
+| F2 | DeepSeek v4 Pro | DeepSeek | ✅ `sk-0387...` |
+| F3 | Gemini 3.5 Flash | Google | ✅ |
+| F4 | Grok 4.5 | xAI | ✅ |
+
+## Admin-AI (LiteLLM)
+- URL: `admin-ai.itpropartner.com` (app1, 152.53.36.131)
+- Master key: in `/root/docker/litellm/.env`
+- Hermes virtual key: `sk-aEJ-7PAPT0C8iqZi3witzA` (GPT-5.5 + DeepSeek v4 Pro)
+
+## Credential Storage
+- Config: `/root/.hermes/config.yaml`
+- Hudu: KB article #39 — "AI Model Chain v2" (if token working)
+- Git: `itpp-infrastructure/docs/model-chain.md`