Guardrails API

The Guardrails API adds safety, privacy, and compliance controls to AssemblyAI transcripts and audio. It covers PII redaction in both transcript text and the underlying audio, profanity filtering, and content moderation, applied as add-ons to a transcription request.

General
DeveloperAssemblyAI
TypeSafety and compliance API
LicenseCommercial API
Documentationassemblyai.com/products/guardrails

Core Features

  • PII text redaction: removes personally identifiable information from transcript text.
  • PII audio redaction: redacts personally identifiable information directly in the audio file.
  • Profanity filtering: filters profane language out of transcript output.
  • Content moderation: flags or filters unsafe or policy-violating content.

Pricing

Guardrails features are billed as add-ons on top of the base Speech-to-Text rate:

Add-onRate
Profanity Filtering+$0.01/hour
PII Text Redaction+$0.08/hour
Content Moderation+$0.15/hour

Source: assemblyai.com/pricing


Use Cases

  • Regulated industries: healthcare and financial services use cases that require PII redaction before storing or sharing transcripts.
  • Customer support and contact centers: content moderation and profanity filtering on recorded or live calls.
  • Compliance workflows: redacting sensitive information from audio archives before retention or sharing.

Ecosystem and Integrations

Guardrails add-ons apply to output from both Speech-to-Text and Universal-Streaming, and can be combined with Speech Understanding add-ons on the same request.


Read the Guardrails docs to add safety and compliance controls to an existing transcription request.

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