Building with coding agents

Most coding tools, from OpenAI-compatible IDEs like Cursor and Zed to terminal agents like OpenCode, Claude Code, Codex, and Factory Droid, let you plug in a custom provider. Point that provider at Merge Gateway and you get every model Gateway supports, including OpenAI, Anthropic, Google, and Kimi, through a single API key. Routing policies, cost governance, and full request observability come built in, visible in the Gateway dashboard.

The three inputs

The OpenAI-compatible IDE guides on this page (Cursor, Zed, Continue.dev) all ask for the same three values:

Input	Value
Base URL	`https://api-gateway.merge.dev/v1/openai`
API key	An organization key from gateway.merge.dev/api-keys, or a project API key created from a project’s API keys tab
Model name	`provider/model` format (for example `anthropic/claude-opus-5`, `openai/gpt-5.5`, or `google/gemini-3.6-flash`), or `default_routing` to let a routing policy pick

Either key type works in every tool. A project API key additionally scopes all of the tool’s usage to that project, so the project’s routing policy and budget apply with nothing else to configure; that’s the recommended way to track and govern coding-agent traffic. Setting the model name to default_routing hands model selection to your routing policy (the key’s project policy or the org default) instead of pinning one model.

Get the full list of available models from GET /v1/models or the models page in the dashboard.

OpenCode, Claude Code, Codex, Pi, and Factory Droid follow different setup shapes (a custom provider in opencode.json, an ANTHROPIC_BASE_URL override, a model provider + profile in ~/.codex/config.toml, a custom provider in ~/.pi/agent/models.json, and a custom model in ~/.factory/settings.json respectively); see their dedicated guides below for the exact config.

Desktop apps route through Gateway too. The Codex desktop app uses top-level keys in ~/.codex/config.toml, and Anthropic’s Claude Desktop (Chat, Cowork, and the built-in Claude Code surface) uses managed configuration (MDM) pointed at Gateway’s Anthropic endpoint.