Redactosaurus

Redactosaurus is a privacy-focused desktop application and browser extension that helps users protect sensitive information when interacting with web-based AI chatbots. It monitors prompt input fields in real time and analyzes the text for potential personally identifiable information (PII) before the message is submitted. Using a local-first processing pipeline powered by NLP tools such as spaCy and Microsoft Presidio, Redactosaurus detects entities like names, email addresses, phone numbers, and physical addresses, then highlights them directly in the prompt interface. Users are notified instantly and can choose to mask or ignore the detected information before sending their prompt. The system operates entirely on-device without transmitting data to external servers, ensuring privacy while improving awareness of what information is being shared with AI systems.

As AI chat assistants become integrated into everyday workflows, users frequently paste or type prompts containing sensitive or confidential information without realizing it. This can include personal data, company secrets, credentials, or internal documentation. Once submitted, that information may be stored or processed by third-party AI services, potentially creating privacy concerns, compliance violations, or security risks. Existing AI interfaces rarely provide safeguards that help users identify sensitive content before submission, leaving individuals and organizations vulnerable to accidental data exposure.

Redactosaurus introduces a protective layer between the user and AI chat interfaces. The tool continuously monitors prompt input areas within supported web-based AI applications and runs real-time entity recognition using a local NLP pipeline. When potential PII is detected, the extension highlights the relevant text segments and alerts the user before the prompt is sent. Users can then mask the information automatically or choose to proceed intentionally. Because the detection engine runs entirely locally, no prompt content is transmitted externally during analysis. The architecture combines lightweight browser extension logic, high-performance Rust components, and NLP models from spaCy and Microsoft Presidio to provide fast, accurate, and privacy-preserving detection.

By introducing real-time prompt awareness, Redactosaurus helps users develop safer habits when interacting with AI systems. It reduces the likelihood of unintentionally exposing sensitive information and encourages better prompt hygiene in both personal and professional contexts. For individuals, it provides an additional privacy safeguard during everyday AI usage. For organizations, it offers a lightweight tool that can help reduce compliance and security risks when employees use AI assistants. Ultimately, Redactosaurus promotes more responsible and privacy-conscious adoption of AI technologies.