---
title: "Connect a model provider"
description: "Wire up Anthropic, Gemini, Claude Agent SDK, a local model via Ollama, OpenAI's Codex CLI, or Cursor: your first connection so you can actually run a workf"
slug: getting-started/connecting-a-provider
section: getting-started
canonical_url: https://cerevisor.com/docs/getting-started/connecting-a-provider
last_verified: 2026-05-18
last_verified_version: "1.2.0"
updated_at: 2026-05-18T15:08:18.053416+00:00
---

Cerevisor doesn't ship its own model. You connect it to a provider you already have access to. Six kinds are supported, and you can have any number of each (except the singletons noted below).

If this is your first launch, the **Provider Setup** modal opens automatically. If you skipped it, open it any time from the title bar menu or via **Settings → Providers → + Add provider**.

This page walks through the simplest setup for each provider type. For the deeper guide, including managing multiple providers, per-agent overrides, and library administration, see [Guides → Providers](../guides/providers/overview.md).

## The six provider types

| Type | What it is | When to use it |
|---|---|---|
| **Anthropic** | Direct API connection to Claude (Opus, Sonnet, Haiku). Cerevisor owns the agent loop. | You have an Anthropic API key and want the most capable hosted models with full Cerevisor control over the loop. Singleton: one entry. |
| **Gemini** | Direct API connection to Google's Gemini (2.5 / 3.x families). Cerevisor owns the agent loop. | You have a Google AI Studio API key and want Gemini's long-context Pro models or its cheap Flash workhorses. Singleton. See the [Gemini provider page](../guides/providers/gemini.md) for the dedicated walkthrough. |
| **Claude Agent SDK** | Anthropic's official Claude Agent SDK runtime running in-process. Delegated loop (Cerevisor sets policy, the SDK runs the loop). | You want Claude Code-style agent execution (read/write/edit/bash/glob/grep tools out of the box) without leaving Cerevisor. Singleton. See the [Claude Agent SDK page](../guides/providers/claude-agent-sdk.md). |
| **OpenAI-compatible** | Any endpoint that speaks the OpenAI Chat Completions API. Includes Ollama, OpenRouter, Together, Groq, Fireworks, vLLM, LM Studio, and OpenAI itself. | You want local models (Ollama), routing across providers (OpenRouter), or anything OpenAI-API-shaped. Multiple entries allowed. |
| **OpenAI Codex CLI** | Sidecar to OpenAI's official `codex` command-line tool. Delegated loop. | You have a ChatGPT subscription (Plus/Pro) and want to use Codex's quota rather than paying per token. Singleton. |
| **Cursor Agent** | In-process Cursor SDK runtime. Delegated loop. | You have a Cursor subscription and want Cursor's agent (with its tool catalog and optional cloud execution). Singleton. |

## Setting up Anthropic

You'll need an API key from [console.anthropic.com](https://console.anthropic.com).

1. In Provider Setup, click **Anthropic**.
2. Paste your API key.
3. Click **Test connection**. Cerevisor calls Anthropic's `/v1/models` endpoint to confirm the key works and to populate the model list.
4. Click **Save**.

The key is stored in your operating system's keychain, never in plain text on disk.

## Setting up Ollama (local models)

You'll need [Ollama](https://ollama.com) installed and at least one model pulled (`ollama pull llama3.1`, for example).

1. In Provider Setup, click **OpenAI-compatible**.
2. **Base URL:** `http://localhost:11434/v1`
3. **API key:** leave blank, or enter any non-empty string: Ollama doesn't check.
4. Click **Test connection**.
5. Pick a default model from the dropdown.
6. Click **Save**.

You can repeat this with different base URLs to add OpenRouter, Groq, Together, or any other OpenAI-shaped endpoint as separate library entries.

## Setting up OpenAI Codex CLI

You'll need Codex installed (`npm install -g @openai/codex`) and a ChatGPT Plus/Pro subscription.

1. In Provider Setup, click **Codex CLI**.
2. The wizard runs `codex --version` to confirm it's installed.
3. The wizard runs `codex login status` to check whether you're already signed in.
4. If you're not signed in, click **Start device auth**. Cerevisor invokes `codex login --device-auth`; copy the URL + code shown into your browser to complete sign-in.
5. The wizard runs a smoke test (`codex exec --json` with a trivial prompt) to confirm everything works end-to-end.
6. Click **Save**.

Cerevisor never stores your OpenAI credentials, Codex owns its own authentication.

> **Windows note:** Cerevisor automatically resolves the `.cmd` shim that `npm install -g` creates for the `codex` command. If the wizard reports "Codex not found" but `codex --version` works in your terminal, restart Cerevisor, PATH is read at launch.

## Setting up Gemini

You'll need an API key from [aistudio.google.com/apikey](https://aistudio.google.com/apikey).

1. In Provider Setup, click **Gemini**.
2. Paste your API key.
3. Click **Test connection**. Cerevisor sends a tiny smoke-test request via the `@google/genai` SDK.
4. Click **Save**.

For the full walkthrough (model list, pricing quirks, thinking budgets), see the [Gemini provider page](../guides/providers/gemini.md).

## Setting up Claude Agent SDK

You'll need an Anthropic API key from [console.anthropic.com](https://console.anthropic.com).

1. In Provider Setup, click **Claude Code (Claude Agent SDK)**.
2. Paste your API key. (The key lives in a dedicated keychain slot, separate from the native Anthropic provider's slot, so you can configure both with the same key without conflict.)
3. Click **Test connection**.
4. Click **Save**.

For the v1.2.0 limitations (no per-tool prompts, no skill injection, etc.), see the [Claude Agent SDK page](../guides/providers/claude-agent-sdk.md).

## Setting up Cursor Agent

You'll need a Cursor account with an API key generated at [cursor.com/dashboard](https://cursor.com/dashboard).

1. In Provider Setup, click **Cursor Agent**.
2. Cerevisor attempts to load the optional `@cursor/sdk` package. If it's not installed, you'll see an install hint.
3. Paste your Cursor API key.
4. Click **Validate**. Cerevisor calls Cursor's identity endpoint to confirm the key.
5. Click **Run smoke test**. Cerevisor spins up a trivial Cursor agent to confirm the local runtime works.
6. Click **Save**.

Cursor runs can also execute in the cloud, see [Guides → Advanced → Cursor cloud runs](../guides/advanced/) for the full setup.

## Setting a default

When you have more than one provider in the library, one of them is marked as the **default**. New workflows use the default automatically; existing workflows keep whatever provider they were saved with.

To change the default: **Settings → Providers**, then click **Set default** on the entry you want.

## Removing a provider

**Settings → Providers**, then click the trash icon on the entry you want to delete.

If any open workflow has an agent that references the credential you're trying to delete, Cerevisor blocks the deletion and shows you which agents would break. Either change those agents to a different provider first, or close the workflow.

## Where to go next

→ [Build and run your first workflow](./your-first-workflow.md)