OpenCode

Configure OpenCode to use LemonData API

Overview

Type: Coding Tool

Primary Path: OpenAI-compatible

Support Confidence: Supported path

OpenCode is an open-source AI coding assistant that runs in your terminal. It supports multiple LLM providers and can be configured to use LemonData’s API for access to 300+ models.

Installation

Install Script

curl -fsSL https://opencode.ai/install | bash

Homebrew

brew install opencode-ai/tap/opencode

Or use the community tap (more frequent updates):

brew install anomalyco/tap/opencode

Go

go install github.com/opencode-ai/opencode@latest

Verify installation:

opencode --version

Configuration

Step 1: Set Environment Variables

export OPENAI_API_KEY="sk-your-lemondata-key"

For permanent configuration, add to ~/.bashrc or ~/.zshrc:

echo 'export OPENAI_API_KEY="sk-your-lemondata-key"' >> ~/.zshrc
source ~/.zshrc

Step 2: Configure OpenCode

OpenCode’s current docs recommend configuring providers through opencode.json or opencode.jsonc. For LemonData, use a custom provider instead of overloading the built-in openai provider:

{
  "$schema": "https://opencode.ai/config.json",
  "provider": {
    "lemondata": {
      "npm": "@ai-sdk/openai-compatible",
      "name": "LemonData",
      "options": {
        "baseURL": "https://api.lemondata.cc/v1",
        "apiKey": "{env:OPENAI_API_KEY}"
      },
      "models": {
        "gpt-5.4": {
          "name": "GPT-5.4"
        },
        "gpt-5-mini": {
          "name": "GPT-5 Mini"
        }
      }
    }
  },
  "model": "lemondata/gpt-5.4"
}

Use @ai-sdk/openai-compatible for chat-completions style compatibility. If you specifically need a provider path built on /v1/responses, OpenCode’s provider docs recommend switching the package to @ai-sdk/openai.

Basic Usage

Start interactive mode:

opencode

Run with a prompt:

opencode "Explain this codebase"

Specify model:

opencode --model lemondata/gpt-5.4 "Fix the bugs in main.py"

Available Models

Model	Best For
gpt-5.4	Complex tasks, code architecture
gpt-5-mini	Quick fixes, simple queries
claude-sonnet-4-6	Code review, documentation
claude-opus-4-6	Complex reasoning
gemini-2.5-flash	Fast responses
deepseek-r1	Algorithm design

Common Commands

Analyze code:

opencode "What does this function do?" < src/utils.ts

Generate code:

opencode "Create a REST API with Express"

Review changes:

git diff | opencode "Review these changes"

Fix errors:

opencode "Fix the TypeScript errors in this project"

Interactive Commands

Command	Description
/help	Show available commands
/model <name>	Switch to a different model
/clear	Clear conversation history
/exit	Exit OpenCode

Troubleshooting

Connection Error

• Verify options.baseURL is set to https://api.lemondata.cc/v1
• Check network connectivity
• Try curl https://api.lemondata.cc/v1/models to test

Authentication Failed

• Verify OPENAI_API_KEY environment variable is set
• Verify options.apiKey references {env:OPENAI_API_KEY} or another valid secret source
• Check that the key starts with sk-
• Ensure the key is active in LemonData dashboard

Model Not Found

• Check model name in config matches exactly
• Verify model availability at lemondata.cc/en/models

Best Practices

Use project context

Run OpenCode from your project root for better understanding of your codebase.

Choose appropriate models

Use faster models (gpt-5-mini) for simple tasks and stronger models (gpt-5.4, claude-sonnet-4-6) for complex ones.

Review generated code

Always review AI-generated code before applying changes to your project.