> ## Documentation Index
> Fetch the complete documentation index at: https://docs.cascadeflow.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Environment Variables

> Environment variable reference for cascadeflow harness configuration, provider API keys, and config file paths.

# Environment Variables

cascadeflow reads configuration from environment variables as part of its resolution chain: Code > Environment Variables > Config Files > Defaults.

## Harness Configuration

| Variable                             | Type                             | Description                     |
| ------------------------------------ | -------------------------------- | ------------------------------- |
| `CASCADEFLOW_HARNESS_MODE`           | `off \| observe \| enforce`      | Harness activation mode         |
| `CASCADEFLOW_HARNESS_BUDGET`         | `float`                          | Budget limit in USD             |
| `CASCADEFLOW_HARNESS_MAX_TOOL_CALLS` | `int`                            | Maximum tool calls allowed      |
| `CASCADEFLOW_HARNESS_MAX_LATENCY_MS` | `float`                          | Maximum latency in milliseconds |
| `CASCADEFLOW_HARNESS_COMPLIANCE`     | `gdpr \| hipaa \| pci \| strict` | Compliance mode                 |
| `CASCADEFLOW_CONFIG`                 | `path`                           | Path to config file             |

## Provider API Keys

| Variable              | Provider     |
| --------------------- | ------------ |
| `OPENAI_API_KEY`      | OpenAI       |
| `ANTHROPIC_API_KEY`   | Anthropic    |
| `GROQ_API_KEY`        | Groq         |
| `TOGETHER_API_KEY`    | Together AI  |
| `OPENROUTER_API_KEY`  | OpenRouter   |
| `HUGGINGFACE_API_KEY` | Hugging Face |

## Resolution Order

When `cascadeflow.init()` is called, settings resolve in this order (first wins):

1. **Code** — arguments passed directly to `init()`, `run()`, or `@agent()`
2. **Environment** — `CASCADEFLOW_HARNESS_*` variables
3. **Config file** — path from `CASCADEFLOW_CONFIG` or default locations
4. **Defaults** — mode=`off`, no budget, no compliance

## Example

```bash theme={null}
# .env
CASCADEFLOW_HARNESS_MODE=observe
CASCADEFLOW_HARNESS_BUDGET=1.00
OPENAI_API_KEY=sk-...
ANTHROPIC_API_KEY=sk-ant-...
```

```python theme={null}
import cascadeflow

# Picks up mode="observe" and budget=1.00 from env
report = cascadeflow.init()
print(report.config_sources)  # Shows where each setting came from
```