deer-flow/frontend/src/content/en/application/configuration.mdx

---
title: Configuration
description: DeerFlow App is configured through two files and a set of environment variables. This page covers the application-level configuration that most operators need to set up before deploying.
---

import { Callout, Cards, Tabs } from "nextra/components";

# Configuration

DeerFlow App is configured through two files and a set of environment variables. This page covers the application-level configuration that most operators need to set up before deploying.

## Configuration files

| File | Purpose |
|---|---|
| `config.yaml` | Backend configuration: models, sandbox, tools, skills, memory, and all Harness settings |
| `extensions_config.json` | MCP servers and skill enable/disable state (managed by the App UI and Gateway API) |

Frontend environment variables control the Next.js build and runtime behavior.

## config.yaml

Start by copying the example:

```bash
cp config.example.yaml config.yaml
```

The most important sections for application configuration are:

### Models

Configure the LLM providers the agent can use. At least one model is required.

<Tabs items={["OpenAI", "Anthropic", "DeepSeek", "Ollama", "Gemini"]}>
  <Tabs.Tab>
```yaml
models:
  - name: gpt-4o
    use: langchain_openai:ChatOpenAI
    model: gpt-4o
    api_key: $OPENAI_API_KEY
    request_timeout: 600.0
    max_retries: 2
    supports_vision: true
```
  </Tabs.Tab>
  <Tabs.Tab>
```yaml
models:
  - name: claude-3-5-sonnet
    use: langchain_anthropic:ChatAnthropic
    model: claude-3-5-sonnet-20241022
    api_key: $ANTHROPIC_API_KEY
    default_request_timeout: 600.0
    max_retries: 2
    max_tokens: 8192
    supports_vision: true
    supports_thinking: true
    when_thinking_enabled:
      thinking:
        type: enabled
    when_thinking_disabled:
      thinking:
        type: disabled
```
  </Tabs.Tab>
  <Tabs.Tab>
```yaml
models:
  - name: deepseek-v3
    use: deerflow.models.patched_deepseek:PatchedChatDeepSeek
    model: deepseek-reasoner
    api_key: $DEEPSEEK_API_KEY
    timeout: 600.0
    max_retries: 2
    supports_thinking: true
    when_thinking_enabled:
      extra_body:
        thinking:
          type: enabled
    when_thinking_disabled:
      extra_body:
        thinking:
          type: disabled
```
  </Tabs.Tab>
  <Tabs.Tab>
```yaml
models:
  - name: qwen3-local
    use: langchain_ollama:ChatOllama
    model: qwen3:32b
    base_url: http://localhost:11434  # No /v1 suffix — uses native Ollama API
    num_predict: 8192
    temperature: 0.7
    reasoning: true
    supports_thinking: true
    supports_vision: false
```

Install Ollama provider: `cd backend && uv add 'deerflow-harness[ollama]'`

<Callout type="warning">
  Use <code>langchain_ollama:ChatOllama</code> (not the OpenAI-compatible
  endpoint) for Ollama models. The native API correctly separates thinking
  content; the OpenAI-compatible endpoint may flatten or drop it.
</Callout>
  </Tabs.Tab>
  <Tabs.Tab>
```yaml
models:
  - name: gemini-2.5-pro
    use: langchain_google_genai:ChatGoogleGenerativeAI
    model: gemini-2.5-pro
    gemini_api_key: $GEMINI_API_KEY
    timeout: 600.0
    max_retries: 2
    max_tokens: 8192
    supports_vision: true
```
  </Tabs.Tab>
</Tabs>

### Sandbox

Choose the execution environment for agent file and command operations:

<Tabs items={["Local (default)", "Docker container", "K8s Provisioner"]}>
  <Tabs.Tab>
```yaml
sandbox:
  use: deerflow.sandbox.local:LocalSandboxProvider
  allow_host_bash: false  # set true only for trusted single-user workflows
```
  </Tabs.Tab>
  <Tabs.Tab>
```yaml
sandbox:
  use: deerflow.community.aio_sandbox:AioSandboxProvider
  image: enterprise-public-cn-beijing.cr.volces.com/vefaas-public/all-in-one-sandbox:latest
  replicas: 3
  idle_timeout: 600
```

Install: `cd backend && uv add 'deerflow-harness[aio-sandbox]'`
  </Tabs.Tab>
  <Tabs.Tab>
```yaml
sandbox:
  use: deerflow.community.aio_sandbox:AioSandboxProvider
  provisioner_url: http://provisioner:8002
```
  </Tabs.Tab>
</Tabs>

### Tools

Configure which tools the agent has access to. The defaults use DuckDuckGo (no API key) and Jina AI for web operations:

```yaml
tools:
  # Web search (choose one)
  - use: deerflow.community.ddg_search.tools:web_search_tool  # default, no key required
  # - use: deerflow.community.tavily.tools:web_search_tool
  #   api_key: $TAVILY_API_KEY

  # Web fetch (choose one)
  - use: deerflow.community.jina_ai.tools:web_fetch_tool

  # Image search
  - use: deerflow.community.image_search.tools:image_search_tool

  # File operations
  - use: deerflow.sandbox.tools:ls_tool
  - use: deerflow.sandbox.tools:read_file_tool
  - use: deerflow.sandbox.tools:glob_tool
  - use: deerflow.sandbox.tools:grep_tool
  - use: deerflow.sandbox.tools:write_file_tool
  - use: deerflow.sandbox.tools:str_replace_tool
  - use: deerflow.sandbox.tools:bash_tool
```

### Thread state persistence (checkpointer)

By default, DeerFlow uses an SQLite checkpointer for thread state persistence:

```yaml
checkpointer:
  type: sqlite
  connection_string: checkpoints.db  # stored in backend/.deer-flow/
```

For production deployments with multiple processes:

```yaml
checkpointer:
  type: postgres
  connection_string: postgresql://user:password@localhost:5432/deerflow
```

Install PostgreSQL support: `cd backend && uv add langgraph-checkpoint-postgres psycopg[binary] psycopg-pool`

For in-memory only (state lost on restart):

```yaml
checkpointer:
  type: memory
```

### Memory

```yaml
memory:
  enabled: true
  storage_path: memory.json
  debounce_seconds: 30
  max_facts: 100
  injection_enabled: true
  max_injection_tokens: 2000
```

## Frontend environment variables

Set these before running `pnpm build` or starting the frontend in production:

| Variable | Required | Description |
|---|---|---|
| `BETTER_AUTH_SECRET` | **Required** in production | Secret for session signing. Use `openssl rand -base64 32`. |
| `BETTER_AUTH_URL` | Recommended | Public-facing base URL (e.g., `https://your-domain.com`) |
| `SKIP_ENV_VALIDATION` | Optional | Set to `1` to skip env validation during build (not recommended) |
| `NEXT_PUBLIC_API_URL` | Optional | Override the API base URL for the frontend |

In development, set these in a `.env` file at the repo root:

```bash
BETTER_AUTH_SECRET=your-strong-secret-here-min-32-chars
```

## extensions_config.json

This file manages MCP server connections and skill enable/disable state. It is created automatically when you first manage extensions through the App UI or Gateway API.

Manual example:

```json
{
  "mcpServers": {
    "my-server": {
      "command": "npx",
      "args": ["-y", "@my-org/my-mcp-server"],
      "enabled": true
    }
  },
  "skills": {
    "deep-research": { "enabled": true },
    "data-analysis": { "enabled": true }
  }
}
```

## Config upgrade

When the config schema changes, `config_version` is bumped. To merge new fields into your existing config without losing customizations:

```bash
make config-upgrade
```

<Cards num={2}>
  <Cards.Card title="Deployment Guide" href="/docs/application/deployment-guide" />
  <Cards.Card title="Harness Configuration" href="/docs/harness/configuration" />
</Cards>