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+---
+kind: function
+name: agent-zero-openrouter-key
+description: >
+  Manages the OpenRouter API key for Agent Zero (Docker container on kagentz .14).
+  Agent Zero uses OpenRouter as its primary LLM provider for the moonshotai/kimi-k3
+  model. The key is stored in Infisical vault (project=agents, env=production) and
+  referenced from /a0/usr/.env in the container. Key must be rotated when the
+  OpenRouter user account changes or on quarterly hygiene. Last verified: 2026-09-01.
+---
+
+## Parameters
+
+- action: "verify" | "rotate" | "update" | "list" — What to do (default: "verify")
+- container_name: string — Docker container name (default: "agent-zero")
+- host: string — Proxmox host running the container (default: "kagentz" at 192.168.68.14)
+- env_path: string — Path to .env file in container (default: "/a0/usr/.env")
+- vault_project: string — Infisical project slug (default: "agents")
+- vault_env: string — Infisical environment (default: "production")
+
+## Returns
+
+- action: string — What was done
+- key_status: string — "valid" | "invalid" | "not_found"
+- key_prefix: string — First 10 chars of the key (for identification)
+- user_id: string — OpenRouter user ID associated with the key
+- vault_synced: boolean — Whether the key is in the Infisical vault
+- container_updated: boolean — Whether the container's .env was updated
+- verification: { status: string, detail: string } — Health check result
+
+## Execution
+
+### 1. Verify the key
+
+1. **Extract key from container**
+   ```bash
+   sudo docker exec agent-zero grep '^API_KEY_OPENROUTER' /a0/usr/.env | cut -d'=' -f2-
+   ```
+
+2. **Test against OpenRouter API**
+   ```bash
+   curl -s https://openrouter.ai/api/v1/auth/key \
+     -H "Authorization: Bearer <key>" | python3 -m json.tool
+   ```
+   Expected: HTTP 200, JSON with `data.label` and `data.is_free_tier`
+
+3. **Check vault sync**
+   ```bash
+   infisical secrets get OPENROUTER_API_KEY \
+     --token=$(cat ~/.infisical-token) \
+     --projectId=agents \
+     --env=production \
+     --domain=https://vault.sysloggh.net
+   ```
+
+4. **Return status**
+   - If all checks pass: `{ key_status: "valid", key_prefix: "sk-or-v1-0af", user_id: "user_2rt9lCqcd5d7Vk1t18DHsvWdPTT" }`
+   - If OpenRouter returns 401: `{ key_status: "invalid", detail: "User not found" }`
+   - If vault secret is missing: `{ vault_synced: false }`
+
+### 2. Rotate the key
+
+1. **Generate new key** in OpenRouter UI or via API
+2. **Update container .env**
+   ```bash
+   sudo docker exec agent-zero sed -i 's/^API_KEY_OPENROUTER=.*/API_KEY_OPENROUTER=<new_key>/' /a0/usr/.env
+   ```
+3. **Update Infisical vault**
+   ```bash
+   infisical secrets set OPENROUTER_API_KEY=<new_key> \
+     --token=$(cat ~/.infisical-token) \
+     --projectId=agents \
+     --env=production \
+     --domain=https://vault.sysloggh.net
+   ```
+4. **Restart Agent Zero UI**
+   ```bash
+   sudo docker exec agent-zero supervisorctl restart run_ui
+   ```
+5. **Verify** — Run "verify" action again
+
+### 3. Update (key changed but no rotation)
+
+1. **Update container .env** (same as rotate step 2)
+2. **Sync vault** (same as rotate step 3)
+3. **Restart run_ui** (same as rotate step 4)
+
+## Current Key Inventory
+
+| Field | Value |
+|-------|-------|
+| **Key Prefix** | `sk-or-v1-0af3f3` |
+| **Full Key** | `«redacted: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»` (in vault + /a0/usr/.env) |
+| **OpenRouter User** | `user_2rt9lCqcd5d7Vk1t18DHsvWdPTT` |
+| **Free Tier** | No |
+| **Monthly Usage** | 0 (as of 2026-09-01) |
+| **Last Verified** | 2026-09-01 |
+
+## Key Rotation Log
+
+| Date | Action | Notes |
+|------|--------|-------|
+| 2026-09-01 | fix-401 | Old key `sk-or-v1-036e5ca5…` returned 401 "User not found". Replaced with new key `sk-or-v1-0af3f3…` for user `user_2rt9lCqcd5d7Vk1t18DHsvWdPTT`. Verified OpenRouter 200. Container .env updated, run_ui restarted. |
+
+## Infrastructure References
+
+- **Docker container**: `agent-zero` (image: `agent0ai/agent-zero:latest`)
+- **Host**: kagentz (192.168.68.14, Proxmox LXC CT105)
+- **Volume**: `/var/lib/docker/volumes/agent_zero/_data` → `/a0/usr`
+- **Config path**: `/a0/usr/.env` (line ~72: `API_KEY_OPENROUTER=…`)
+- **Model preset**: "Cost Efficient" (uses `openrouter/moonshotai/kimi-k3`)
+- **Model config**: `/a0/usr/plugins/_model_config/config.json`
+
+## Verification Before Acting
+
+**Key is a lead, not a fact.** Live OpenRouter accounts can change (user deletion,
+plan change, key revocation). Before acting on this contract:
+
+1. Verify the key against OpenRouter's `/auth/key` endpoint
+2. Check the user ID matches the expected account
+3. Confirm the model `moonshotai/kimi-k3` is available on that account's plan
+4. Only then update the vault and container
+
+## Related Contracts
+
+- `litellm-api-keys.prose.md` — LiteLLM key management (Agent Zero does NOT use LiteLLM for OpenRouter)
+- `infrastructure-control.prose.md` — Proxmox topology, container locations
+- `gpu-fleet.prose.md` — Fleet-wide agent key inventory (add Agent Zero here)