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Preview of Contextia

Contextia by Contextia

Catch API keys, tokens and credentials before you paste them into an AI chat. Local and on-device: nothing leaves your machine.

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Extension Metadata

Screenshots
A detected secret in the chat composerReview each finding and choose what to doThe prompt after redactionLocal stats and recent detectionsSettings: modes, detectors, allow and redact lists
About this extension
Contextia is a local, privacy-first guard that flags secrets in the chat composer
before they ever leave your machine.

Developers paste code, logs and configs into AI chats every day, and those often
contain live API keys, tokens, private keys and connection strings. Contextia
catches them at the moment of typing or pasting, entirely on your device.

What it does:
• Detects over 80 kinds of credential, covering cloud provider keys, source
control and package registry tokens, payment and messaging service keys, AI
provider keys, PEM private keys, .env secrets, database connection strings
and JWTs.
• Optionally flags personal data as well: card numbers validated by checksum,
IBANs and national identifiers. Off unless you turn them on.
• Explains why each match was flagged, so it is never a mystery.
• Underlines the offending text and offers Redact, Allow once, Allow all, or
Allow this pattern always.
• Lets you add your own values and regular expressions to always redact.
• Four modes: Warn, Auto-redact before sending, Block until resolved, or Off.
• Keeps a local detections log and counters on your device. Never the secret
value itself.

Privacy by construction:
• Nothing leaves your machine. No accounts, no servers, no telemetry, no third
parties.
• Zero network requests by default. You may optionally mirror catch counts,
never the secret, to a dashboard on your own machine over loopback. It is off
unless you enable it and refuses any address that is not loopback.
• Runs only on the AI chat sites listed in the permissions, and requests no
other access.
• Open source under the MIT licence. Audit every line:
https://github.com/sbr0nch/contextia

Contextia is a safety net, not a guarantee: rule-based detection can miss things,
so treat it as a guardrail, not proof that a paste is clean.
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Permissions and data

Required permissions:

  • Access your data for chatgpt.com
  • Access your data for claude.ai
  • Access your data for gemini.google.com
  • Access your data for aistudio.google.com
  • Access your data for copilot.microsoft.com
  • Access your data for www.perplexity.ai
  • Access your data for chat.deepseek.com

Optional permissions:

  • Access your data for chatgpt.com
  • Access your data for claude.ai
  • Access your data for gemini.google.com
  • Access your data for aistudio.google.com
  • Access your data for copilot.microsoft.com
  • Access your data for www.perplexity.ai
  • Access your data for chat.deepseek.com

Data collection:

  • The developer says this extension doesn't require data collection.
Learn more
More information
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Version
2.0.3
Size
57.99 KB
Last updated
a day ago (Jul 26, 2026)
Related Categories
  • Web Development
  • Privacy & Security
License
MIT License
Privacy Policy
Read the privacy policy for this add-on
Version History
  • See all versions
Tags
  • privacy
  • security
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