@hellogravel/opencode-lms

An LM Studio provider plugin for OpenCode.

What it does

• Discovers the chat models your LM Studio server is hosting and exposes them in OpenCode. Embedding models are filtered out by default (OpenCode has no slot that consumes them); list one in provider.lmstudio.models to opt it back in.
• Loads an unloaded LLM on first reference; load progress is logged to the OpenCode server log.
• Forwards an Authorization: Bearer … header to LM Studio when apiKey is set.
• Demotes reasoning_effort: "max" to "xhigh" before requests leave OpenCode, since LM Studio rejects max.
• Sets each model's OpenCode capability flags from what LM Studio reports — reasoning, tool_call, attachment (vision models), temperature, family, etc. — and marks reasoning-capable models with interleaved: { field: "reasoning_content" } so OpenCode renders the streaming reasoning trace live in the TUI.
• Suppresses OpenCode's auto-generated reasoning-effort picker (low/medium/high) for models that only support binary on/off reasoning, since every choice would route to "on" inside LM Studio anyway. Graduated reasoning models keep the picker.

Set up

Add the plugin and provider to ~/.config/opencode/opencode.jsonc:

{
  "provider": {
    "lmstudio": {
      "name": "LM Studio",
      "options": {
        "baseURL": "http://127.0.0.1:1234",
        "apiKey": "sk-lm-..."
      }
    }
  },
  "model": "lmstudio/google/gemma-4-26b-a4b",
  "plugin": ["@hellogravel/opencode-lms"]
}

Start LM Studio's server (lms server start) and restart OpenCode.

• This plugin extends OpenCode's built-in lmstudio provider in place — it supplies the live model list via OpenCode's provider.models hook. Do not add lmstudio to disabled_providers, or the plugin's models get disabled too.
• apiKey is only needed when LM Studio has API token auth enabled.
• baseURL should not include a /v1 suffix — the plugin appends it.

Upgrading from a pre-0.2 build? The provider id changed from lms to lmstudio. Rename the provider.lms config key to provider.lmstudio, update any "model": "lms/…" reference to "lmstudio/…", and drop the old "disabled_providers": ["lmstudio"] line.

Options

Under provider.lmstudio.options:

Option	Type	Default	Description
baseURL	string	"http://127.0.0.1:1234"	LM Studio server URL
apiKey	string	—	Bearer token sent in the Authorization header
autoDetect	boolean	true	When baseURL is not set, probe localhost ports 1234, 8080, 11434
disableAutoLoad	boolean	false	Skip the auto-load step on first model reference
autoDownload	boolean	false	Download a missing model on first reference (off by default — a typo could trigger a multi-GB download)
loadTimeout	number	600000	Load/unload timeout in ms
downloadTimeout	number	1800000	Download timeout in ms
timeout	number	600000	Overall chat-completion request timeout in ms
chunkTimeout	number	120000	Inter-chunk (time-to-next-token) timeout in ms — raise for SWA models (see note)

SWA models (e.g. Gemma) and chunkTimeout: llama.cpp can't reuse the prompt cache for sliding-window-attention models, so every turn reprocesses the entire prompt from scratch. No streamed chunks are emitted during that prompt-processing phase, so a large prompt can exceed chunkTimeout before the first token — the request aborts and retries, reprocessing from 0% again, looping indefinitely. If you see prompt processing restart from 0% repeatedly, raise chunkTimeout (e.g. to match timeout) and/or shrink the prompt by disabling unused tools/MCP servers.

Model overrides

Override per-model metadata under provider.lmstudio.models[<id>]:

"models": {
  "google/gemma-4-e4b": {
    "name": "Gemma 4 E4B",
    "reasoning": true,
    "limit": { "context": 131072, "output": 131072 }
  }
}

Field	Type	Description
id	string	LM Studio model identifier (e.g. google/gemma-4-e4b)
name	string	Display name
reasoning	boolean	Mark the model as reasoning-capable
tool_call	boolean	Mark the model as supporting tool calls
modalities	object	e.g. { input: ["text","image"], output: ["text"] }
limit	object	{ context: <ctx>, output: <out> }

Overrides merge on top of discovered models.

Development

git clone https://github.com/hellogravel/opencode-lms
cd opencode-lms
npm install
npm run build       # Compile TypeScript → dist/
npm run typecheck
npm run test:run

For a containerized OpenCode runtime with this plugin loaded, see docker/.

test-live.mjs exercises the plugin against a live LM Studio server:

npm run build
LMS_BASE_URL=http://192.168.1.10:1234 \
LMS_API_KEY=sk-lm-... \
  node test-live.mjs

License

MIT