> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://respan.ai/docs/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://respan.ai/docs/_mcp/server.

# Eve (gateway)

> Route Eve model calls through the Respan gateway with an AI SDK provider model.

Eve accepts provider-authored AI SDK language models. Configure an OpenAI-compatible provider for Respan to route Eve model calls through the Respan gateway with one API key.

> **Note**
>
> An Eve string model such as `"openai/gpt-5.4-mini"` uses Vercel AI Gateway. To use Respan Gateway, pass the provider model object shown below. `AI_GATEWAY_API_KEY` is a Vercel AI Gateway credential and is not used by this setup.

## Setup

#### Install packages

```bash
npm install eve@0.26.1 ai@7.0.26 @ai-sdk/openai@4.0.16
```

Eve 0.26 requires Node.js 24 or newer.

#### Set the Respan API key

```bash
export RESPAN_API_KEY="YOUR_RESPAN_API_KEY"
```

No provider API key is required. The Respan gateway handles provider authentication.

#### Configure the Eve model

Create or update `agent/agent.ts`. Eve also expects `agent/instructions.md` (or an `instructions/` directory), which `eve init` creates for you:

**`agent/agent.ts`**

```typescript agent/agent.ts
import { createOpenAI } from "@ai-sdk/openai";
import { defineAgent } from "eve";

const respan = createOpenAI({
  apiKey: process.env.RESPAN_API_KEY!,
  baseURL: "https://api.respan.ai/api",
});

export default defineAgent({
  model: respan.chat("gpt-5.5"),
});
```

With AI SDK 7, call `respan.chat(...)` explicitly. Calling `respan(...)` selects the Responses API, while this key-only configuration uses Respan's Chat Completions route.

#### Run Eve

```bash
npx eve dev
```

## Switch models

Keep the provider configuration and replace `gpt-5.5` with another identifier from the [full model list](https://platform.respan.ai/platform/models). Provider prefixes make cross-provider routing explicit.

> **Note**
>
> Eve's provider-managed `web_search` tool is not available through this OpenAI-compatible Chat Completions route. Use an authored Eve tool when your agent needs web search.