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KochC
KochC

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Use any OpenCode model from Open WebUI, LangChain, or the OpenAI SDK — with a one-line install

#openai #llm #node #javascript

If you use OpenCode, you already have GitHub Copilot, Ollama, Anthropic, Gemini, and other providers configured in one place.
The problem: every other tool in your workflow — Open WebUI, LangChain, Chatbox, Continue, Zed, your own scripts — needs the same models re-entered with their own API keys and base URLs.
I built opencode-llm-proxy to fix this. It's an OpenCode plugin that starts a local HTTP server on http://127.0.0.1:4010 and translates between whatever API format your tool uses and OpenCode's model list.

Install 

npm install opencode-llm-proxy
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Add to opencode.json:

{ "plugin": ["opencode-llm-proxy"] }
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Start OpenCode — the proxy starts automatically.

Supported API formats

All formats support streaming.

Format Endpoint
OpenAI Chat Completions POST /v1/chat/completions
OpenAI Responses API POST /v1/responses
Anthropic Messages API POST /v1/messages
Google Gemini POST /v1beta/models/:model:generateContent

Examples

OpenAI SDK (Python) — route to Ollama 

from openai import OpenAI
client = OpenAI(base_url="http://127.0.0.1:4010/v1", api_key="unused")
response = client.chat.completions.create(
    model="ollama/qwen2.5-coder",
    messages=[{"role": "user", "content": "Write a binary search in Python."}],
)
print(response.choices[0].message.content)
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Anthropic SDK (Python) — route to GitHub Copilot 

import anthropic
client = anthropic.Anthropic(base_url="http://127.0.0.1:4010", api_key="unused")
message = client.messages.create(
    model="github-copilot/claude-sonnet-4.6",
    max_tokens=1024,
    messages=[{"role": "user", "content": "Explain the CAP theorem."}],
)
print(message.content[0].text)
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OpenAI SDK (JavaScript) 

import OpenAI from "openai"
const client = new OpenAI({ baseURL: "http://127.0.0.1:4010/v1", apiKey: "unused" })
const response = await client.chat.completions.create({
  model: "anthropic/claude-3-5-sonnet",
  messages: [{ role: "user", content: "Explain async/await." }],
})
console.log(response.choices[0].message.content)
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Open WebUI

Settings → Connections → set API Base URL to http://127.0.0.1:4010/v1. All your OpenCode models appear in the model picker instantly.

LangChain (Python) 

from langchain_openai import ChatOpenAI
llm = ChatOpenAI(
    model="anthropic/claude-3-5-sonnet",
    openai_api_base="http://127.0.0.1:4010/v1",
    openai_api_key="unused",
)
response = llm.invoke("What are the SOLID principles?")
print(response.content)
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How it works

Each request:

  1. Authenticates (optional bearer token via OPENCODE_LLM_PROXY_TOKEN)
  2. Resolves the model ID — provider/model notation, bare model ID, or Gemini URL path
  3. Creates a temporary OpenCode session
  4. Sends the prompt via the OpenCode SDK
  5. Returns the response in the same API format as the request Model IDs come from GET /v1/models, which returns all configured providers in OpenAI list format: 
curl http://127.0.0.1:4010/v1/models | jq '.data[].id'
# "github-copilot/claude-sonnet-4.6"
# "anthropic/claude-3-5-sonnet"
# "ollama/qwen2.5-coder"
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Configuration

Variable Default Description
OPENCODE_LLM_PROXY_HOST 127.0.0.1 Bind address. Set to 0.0.0.0 to expose on LAN or Docker.
OPENCODE_LLM_PROXY_PORT 4010 TCP port.
OPENCODE_LLM_PROXY_TOKEN (unset) Bearer token required on every request.
OPENCODE_LLM_PROXY_CORS_ORIGIN * Access-Control-Allow-Origin for browser clients.

GitHub · npm

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