Guides / Gemini SDK

Use Gemini SDK with llmapi.cheap

Run Gemini SDK on Gemini 3.8 Flash, Claude Sonnet 4.6, Claude Opus 4.6 or GPT-OSS with a single llmapi.cheap key. Plans start at $2 a month, and there is a free one-hour trial.

Protocol: Gemini

Setup

Use the native Gemini API shape:

curl "https://llmapi.cheap/v1beta/models/gemini-3.8-flash-high:generateContent" \
  -H "x-goog-api-key: YOUR_API_KEY" \
  -d '{"contents":[{"parts":[{"text":"Hello"}]}]}'

Endpoints

Use the base URL that matches the protocol your tool speaks.

OpenAI
https://llmapi.cheap/v1
Anthropic
https://llmapi.cheap
Gemini
https://llmapi.cheap/v1beta
Models
https://llmapi.cheap/v1/models

Model IDs

Any of these work wherever Gemini SDK asks for a model name. Gemini 3.8 Flash (high) is the default the setup command picks.

Model IDModel
gemini-3.8-flash-highGemini 3.8 Flash, high reasoning (default)
gemini-3.8-flashGemini 3.8 Flash, medium reasoning
gemini-3.8-flash-lowGemini 3.8 Flash, low reasoning
gemini-3.1-pro-highGemini 3.1 Pro, high reasoning
gemini-3.1-pro-lowGemini 3.1 Pro, low reasoning
gemini-3-flashGemini 3 Flash
claude-sonnet-4-6Claude Sonnet 4.6
claude-opus-4-6Claude Opus 4.6
gpt-oss-120bGPT-OSS 120B

Troubleshooting

  • 401 / invalid key: check the key starts with sk-llm- and has no extra spaces. Create a new one under Dashboard → API keys if needed.
  • Model not allowed: the free trial covers the Gemini models; Claude and GPT-OSS come with any paid plan.
  • 404 on requests: OpenAI-style tools need https://llmapi.cheap/v1; Anthropic-style tools need https://llmapi.cheap without /v1.