> For the complete documentation index, see [llms.txt](https://docs.greennode.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.greennode.ai/ai-stack/agent-base/ai-coding/opencode-with-maas-model.md). # Use OpenCode with GreenNode MaaS > Configure [OpenCode](https://opencode.ai) — a TUI coding assistant — to call models through GreenNode MaaS via the `@ai-sdk/openai-compatible` provider, billed via internal credit-tokens. *** ## Prerequisites * An active [AI Platform](https://aiplatform.console.greennode.ai/) account * API key (`vn-...` token) with status **ACTIVE** * Node.js installed *** ## Step 1 — Install OpenCode ```bash npm install -g opencode-ai ``` Or via Homebrew (macOS): ```bash brew install opencode ``` *** ## Step 2 — Get an API key from AI Platform 1. Log in to [AI Platform Console](https://aiplatform.console.greennode.ai/) 2. Go to **API Keys** → **Create API Key** 3. Name the key (5–50 chars, lowercase letters, numbers, and hyphens) 4. Copy the API key (`vn-...`) {% hint style="warning" %} A newly created API key has status `pending`. Wait until the status is `ACTIVE` before using it. {% endhint %} *** ## Step 3 — Create the `opencode.json` config file Create `opencode.json` at the project root: ```json { "$schema": "https://opencode.ai/config.json", "model": "MAAS-chat/openai/gpt-oss-120b", "provider": { "MAAS-chat": { "npm": "@ai-sdk/openai-compatible", "name": "MAAS chat", "options": { "baseURL": "https://maas-llm-aiplatform-hcm.api.vngcloud.vn/v1", "apiKey": "{env:MAAS_API_KEY}" }, "models": { "openai/gpt-oss-120b": { "name": "openai/gpt-oss-120b" } } } } } ``` **Field reference:** | Field | Purpose | | -------------------- | --------------------------------------------------------------------------------- | | `$schema` | Enables editor autocomplete and validation | | `model` | Default model — format is `/` | | `provider.MAAS-chat` | Provider key — the part before `/` in `model` must match exactly | | `npm` | Adapter package — `@ai-sdk/openai-compatible` works for any OpenAI-style endpoint | | `options.baseURL` | MaaS endpoint, including the `/v1` suffix | | `options.apiKey` | MaaS token — use `{env:MAAS_API_KEY}` instead of a hardcoded value | | `models` | Models to expose from this provider | {% hint style="warning" %} Common mistake: setting `"model"` to a value that does not match a registered provider key. OpenCode resolves `model` by splitting on the first `/` and looking up the provider. If it doesn't match a `provider.*` entry, the model fails to load. Always use `MAAS-chat/openai/gpt-oss-120b`. {% endhint %} *** ## Step 4 — Provide the API key Because the config uses `{env:MAAS_API_KEY}`, the key is never stored in the file — OpenCode reads it from the environment variable at runtime. Two options: **Option A — Export the environment variable (recommended)** Export the key in your shell, then launch OpenCode in the same session: ```bash export MAAS_API_KEY="vn-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" opencode ``` To set it automatically on every terminal open, add it to `~/.zshrc` or `~/.bashrc`: ```bash echo 'export MAAS_API_KEY="vn-xxxx..."' >> ~/.zshrc source ~/.zshrc ``` Or set it inline for a single run: ```bash MAAS_API_KEY="vn-xxxx..." opencode ``` **Option B — Use a gitignored `.env` file in the project** Create a `.env` file (add to `.gitignore`): ```bash export MAAS_API_KEY="vn-xxxx..." ``` Source it before launching OpenCode: ```bash source .env && opencode ``` {% hint style="warning" %} Do not hardcode the API key directly in `opencode.json` if the file is committed to git. If a key has already been committed, rotate it immediately in the MAAS Console — once pushed, it must be treated as compromised. {% endhint %} *** ## Step 5 — Run OpenCode and select the model 1. Navigate to the project directory and run: ```bash opencode ``` OpenCode starts with `MAAS-chat/openai/gpt-oss-120b` as the active model. 2. Switch models at runtime with the `/models` command, then pick **MAAS chat → openai/gpt-oss-120b** from the list.

OpenCode running with openai/gpt-oss-120b via GreenNode MaaS

*** ## Adding more MaaS models To expose additional models from the same MaaS endpoint, add entries under `models`: ```json "models": { "openai/gpt-oss-120b": { "name": "openai/gpt-oss-120b" }, "openai/gpt-oss-20b": { "name": "openai/gpt-oss-20b" } } ``` Then select them via `/models`, or update the top-level `model` field to `MAAS-chat/`. *** ## Troubleshooting | Symptom | Cause | Fix | | --------------------------------------- | ------------------------------------------ | ---------------------------------------------------------- | | `provider not found` / model won't load | `model` value doesn't match a provider key | Use `MAAS-chat/openai/gpt-oss-120b` | | `401 Unauthorized` | Missing, expired, or inactive API key | Re-export `MAAS_API_KEY`; rotate the token in MAAS Console | | `404` on requests | Wrong base URL or missing `/v1` | Confirm `baseURL` ends with `/v1` | | Connection timeout | Endpoint unreachable from your network | Check VPN / connectivity to `*.api.vngcloud.vn` | | Model returns errors but auth is fine | Incorrect model ID | Use the exact ID MaaS publishes (`openai/gpt-oss-120b`) | *** ## Result After completing setup, OpenCode routes all requests through GreenNode MaaS. Usage is recorded on [AI Platform Console → Usage](https://aiplatform.console.greennode.ai/). | I want to... | Go to | | ------------------------------- | ------------------------------------------------------------------------------------------------------ | | Use Codex with Minimax via MaaS | [Use Codex with Minimax via GreenNode MaaS](/ai-stack/agent-base/ai-coding/use-codex-with-minimax.md) | | Connect Claude Code to MaaS | [Connect Claude Code to GreenNode MaaS](/ai-stack/agent-base/ai-coding/connect-claude-code-to-maas.md) | | View usage and billing | [AI Platform Console](https://aiplatform.console.greennode.ai/) |