Skip to content

Secret Redaction

The secret_redaction guardrail detects API keys, passwords, and other secrets that may have leaked into LLM responses.

Import

from pydantic_ai_guardrails.guardrails.output import secret_redaction

Basic Usage

from pydantic_ai_guardrails import GuardedAgent
from pydantic_ai_guardrails.guardrails.output import secret_redaction

guarded_agent = GuardedAgent(
    agent,
    output_guardrails=[
        secret_redaction(),
    ],
)

Parameters

Parameter	Type	Default	Description
`patterns`	`list[str] \| None`	Default patterns	Custom regex patterns

Default Patterns

The guardrail detects these secret patterns by default:

Type	Pattern	Example
OpenAI API key	`sk-[a-zA-Z0-9]{32,}`	`sk-abc123...`
AWS Access Key	`AKIA[A-Z0-9]{16}`	`AKIAIOSFODNN7EXAMPLE`
GitHub Token	`ghp_[a-zA-Z0-9]{36}`	`ghp_abc123...`
Generic API Key	`api[_-]?key[=:]\s*\S+`	`api_key=xyz123`
Password	`password[=:]\s*\S+`	`password=secret`
Bearer Token	`Bearer\s+[a-zA-Z0-9._-]+`	`Bearer eyJ...`

Examples

Default Detection

guardrail = secret_redaction()

Custom Patterns

guardrail = secret_redaction(
    patterns=[
        r'sk-[a-zA-Z0-9]{32,}',           # OpenAI
        r'AKIA[A-Z0-9]{16}',               # AWS
        r'my-company-key-[a-z0-9]{20}',    # Custom company format
    ],
)

Violation Result

When triggered, returns:

{
    'tripwire_triggered': True,
    'message': 'Potential secrets detected in output',
    'severity': 'critical',
    'metadata': {
        'patterns_matched': ['openai_api_key', 'aws_access_key'],
    },
    'suggestion': 'Remove or redact all API keys and secrets from the response',
}

Use Cases

Data protection: Prevent accidental exposure of credentials
Compliance: Meet security requirements
Training safety: Catch model leaking training data
API security: Protect keys from logs and responses

Combine with max_retries to automatically let the LLM redact secrets:

guarded_agent = GuardedAgent(
    agent,
    output_guardrails=[secret_redaction()],
    max_retries=2,  # LLM will retry without secrets
)