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

# Microsoft Presidio

> Use Microsoft Presidio Analyzer with Bifrost Guardrails for configurable PII detection, blocking, and redaction.

## Overview

Bifrost Enterprise supports **Microsoft Presidio** as a guardrail provider for PII detection. Bifrost sends selected request or response text to a Presidio Analyzer service, then applies the configured action: detect, block, or redact.

Use Presidio when you want a self-hosted or privately deployed PII analyzer with configurable entity filters and score thresholds.

## How It Works

1. You deploy or provide a Presidio Analyzer endpoint.
2. You create a guardrail provider with `provider_name: "presidio"`.
3. You optionally choose Presidio entity types and a score threshold.
4. You attach the provider to one or more guardrail rules.
5. Bifrost sends text blocks to Presidio's `/analyze` endpoint.
6. Bifrost applies the configured `action`.

Presidio currently evaluates text content. It does not inspect image pixels or arbitrary binary file contents.

## Capabilities

* PII detection through Presidio Analyzer
* Optional entity filtering with `entities`
* Optional score threshold with `score_threshold`
* `detect_only`, `block`, and `redact` actions
* Bifrost-managed redaction strategies and modes
* Supported-entities lookup through the configured Analyzer service

## Configuration Fields

| Field                | Type    | Required | Default                | Description                                                                      |
| -------------------- | ------- | -------- | ---------------------- | -------------------------------------------------------------------------------- |
| `analyzer_url`       | string  | Yes      | -                      | Base URL for the Presidio Analyzer service. Bifrost appends `/analyze`.          |
| `api_key`            | string  | No       | -                      | Optional API key. Supports `env.PRESIDIO_API_KEY`.                               |
| `language`           | string  | No       | `en`                   | Language sent to Presidio Analyzer.                                              |
| `score_threshold`    | number  | No       | `0.5`                  | Minimum Presidio score to keep, from `0` to `1`.                                 |
| `entities`           | array   | No       | all supported entities | Presidio entity types to detect.                                                 |
| `action`             | enum    | No       | `detect_only`          | `detect_only`, `block`, or `redact`.                                             |
| `redaction_strategy` | enum    | No       | `replace`              | `replace`, `mask`, or `hash`. Used when `action` is `redact`.                    |
| `redaction_mode`     | enum    | No       | `runtime`              | `runtime`, `logs_only`, or `runtime_reversible`. Used when `action` is `redact`. |
| `timeout`            | integer | No       | provider default       | Provider execution timeout in seconds.                                           |

For the full redaction behavior matrix, see [Guardrail Redaction](/enterprise/guardrails/redaction).

## Configuration

<Tabs group="presidio-config">
  <Tab title="Web UI">
    1. Go to **Guardrails** > **Providers**.
    2. Select **Microsoft Presidio**.
    3. Click **Add Configuration**.
    4. Enter your Analyzer URL.
    5. Optionally set an API key, language, score threshold, and entity filters.
    6. Choose an action. Select **Redact** to enable Bifrost-managed redaction.
    7. If redacting, choose the redaction strategy and mode.
    8. Save the configuration and attach it to a guardrail rule.
  </Tab>

  <Tab title="API">
    ```bash theme={null}
    curl -X POST http://localhost:8080/api/guardrails/presidio \
      -H "Content-Type: application/json" \
      -d '{
        "name": "presidio-pii-redaction",
        "enabled": true,
        "config": {
          "analyzer_url": "https://presidio.company.com",
          "api_key": "env.PRESIDIO_API_KEY",
          "language": "en",
          "score_threshold": 0.75,
          "entities": ["EMAIL_ADDRESS", "PHONE_NUMBER", "PERSON"],
          "action": "redact",
          "redaction_strategy": "replace",
          "redaction_mode": "runtime_reversible"
        }
      }'
    ```
  </Tab>

  <Tab title="config.json">
    ```json theme={null}
    {
      "guardrails_config": {
        "guardrail_providers": [
          {
            "id": 30,
            "provider_name": "presidio",
            "policy_name": "presidio-pii-redaction",
            "enabled": true,
            "timeout": 10,
            "config": {
              "analyzer_url": "https://presidio.company.com",
              "api_key": "env.PRESIDIO_API_KEY",
              "language": "en",
              "score_threshold": 0.75,
              "entities": ["EMAIL_ADDRESS", "PHONE_NUMBER", "PERSON"],
              "action": "redact",
              "redaction_strategy": "replace",
              "redaction_mode": "runtime_reversible"
            }
          }
        ]
      }
    }
    ```
  </Tab>

  <Tab title="Helm">
    ```yaml theme={null}
    bifrost:
      guardrails:
        providers:
          - id: 30
            provider_name: "presidio"
            policy_name: "presidio-pii-redaction"
            enabled: true
            timeout: 10
            config:
              analyzer_url: "https://presidio.company.com"
              api_key: "env.PRESIDIO_API_KEY"
              language: "en"
              score_threshold: 0.75
              entities:
                - "EMAIL_ADDRESS"
                - "PHONE_NUMBER"
                - "PERSON"
              action: "redact"
              redaction_strategy: "replace"
              redaction_mode: "runtime_reversible"
    ```
  </Tab>
</Tabs>

## Entity Filters

Leave `entities` empty to let Presidio return all entities supported by your Analyzer configuration. Set `entities` when you want a narrower policy, for example only `EMAIL_ADDRESS` and `PHONE_NUMBER`.

Bifrost can fetch supported entities from:

```text theme={null}
GET {analyzer_url}/supportedentities?language={language}
```

That entity catalog powers the multi-select experience in the UI when the configured Analyzer is reachable.

## Operational Notes

* Presidio offsets are converted into Go byte ranges before redaction.
* `score_threshold: 0` is valid and is sent explicitly to Presidio.
* The default action is `detect_only`, so set `action: "redact"` or `action: "block"` when you want enforcement.
* Redaction modes affect Bifrost runtime payloads, Bifrost logs, and trace-export connectors as described in [Guardrail Redaction](/enterprise/guardrails/redaction).