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

# Authentication

> Learn how to configure credentials and authenticate with the Perceptron SDK.

To configure credentials, you can set environment variables directly in your code, use the `configure()` helper to set them for the process, or use the `config()` context manager to set them for a single context.

### Environment variables

If you're setting environment variables directly, you can set the following. The SDK will use them at runtime:

```bash theme={null}
export PERCEPTRON_PROVIDER="perceptron" # for now, either "perceptron" or "fal"
export PERCEPTRON_API_KEY="<your_api_key_here>" # your Perceptron API key or Fal API key
export PERCEPTRON_BASE_URL="<optional_base_url_here>" # [optional] can include a separate base URL
```

### Direct calls

If you're using the `configure()` helper, you can pass in the credentials directly:

```python theme={null}
from perceptron import configure
configure(
    provider="perceptron",
    api_key="<your_api_key_here>",
    base_url="<optional_base_url_here>",
)
```

### Context manager

You can also use the `config()` context manager when you need a one-off override—for example, to bump timeouts or retries around a specific call:

```python theme={null}
from perceptron import config

with config(timeout=60, retries=3):
    caption("inspection.png")
```

## Configurable fields

**Fields for `configure()` as a standalone function or the `config()` context manager:**

| Setting                   | Default                                        | Description                                                            |
| ------------------------- | ---------------------------------------------- | ---------------------------------------------------------------------- |
| `base_url`                | `None`                                         | Override the Perceptron endpoint (e.g., edge gateway).                 |
| `api_key`                 | `None`                                         | API key to send with requests.                                         |
| `provider`                | `None` → auto-detected (`"fal"` when relevant) | Transport/provider name.                                               |
| `model`                   | `None`                                         | Preferred model ID if your provider exposes multiple versions.         |
| `timeout`                 | `60.0`                                         | Per-request timeout in seconds.                                        |
| `retries`                 | `3`                                            | Automatic retry attempts on transient errors.                          |
| `strict`                  | `False`                                        | Enforce strict parsing (raises on schema mismatches).                  |
| `allow_multiple`          | `False`                                        | Allow multiple responses when the task permits it.                     |
| `warn_on_implicit_anchor` | `True`                                         | Emit warnings if prompts rely on implicit spatial anchors.             |
| `temperature`             | `None`                                         | Generation temperature for text answers.                               |
| `max_tokens`              | `None`                                         | Token cap for generations.                                             |
| `top_p`                   | `None`                                         | Nucleus sampling parameter.                                            |
| `top_k`                   | `None`                                         | Limits sampling to the top-k candidates when set.                      |
| `max_buffer_bytes`        | `None`                                         | Caps streamed buffer size (useful for long outputs).                   |
| `resize_max_side`         | `None`                                         | Downscale images so the longest side matches this value before upload. |
| `auto_coerce_paths`       | `False`                                        | Automatically open local file paths passed into SDK helpers.           |

Settings resolve in this order: per-call arguments → decorator defaults → `configure` / context manager → environment variables → library defaults.