Pastewatch

Detects and obfuscates sensitive data before it reaches AI systems — clipboard monitoring, CLI scanner, MCP server, API proxy, shell guard hooks, and VS Code extension.

It operates before paste, not after submission.

If sensitive data never enters the prompt, the incident does not exist.

Core Principle

Principiis obsta - resist the beginnings.

Pastewatch intervenes at the earliest irreversible boundary: the moment data leaves the user's control.

Once pasted into an AI system, data cannot be reliably recalled, audited, or constrained.

Pastewatch refuses that transition.

Why This Matters

Every AI agent sends your file contents, command outputs, and tool results to a cloud API. If those contain secrets, the secrets leave your machine — silently, irreversibly, and into infrastructure you don't control.

Pastewatch makes secret leakage structurally impossible without breaking any agent functionality:

  What the agent does                What actually happens
  ──────────────────                 ──────────────────────
  Read a file with secrets     →    MCP returns placeholders, secrets stay in RAM
  Run a bash command with DSN  →    Guard blocks before execution
  Send tool results to API     →    Proxy redacts secrets from the request body
  Write code with placeholders →    MCP resolves originals locally on write-back

The agent works normally. It reads files, runs commands, writes code. It just never sees the real values — and neither does the cloud.

No behavioral rules. No trust assumptions. No ML. The architecture prevents the leak.

Why Pastewatch

• Before-paste boundary — secrets never leave your machine. Nightfall, Prisma, Check Point all intercept downstream. Pastewatch prevents upstream
• MCP server for AI agents — no other tool provides redacted read/write at the tool level. The agent works with placeholders, your secrets stay local
• Bash guard with deep parsing — pipes, subshells, redirects, database CLIs, infra tools. Every shell command the agent runs is scanned before execution
• API proxy — catches everything, including subagents and tools that bypass hooks. Last line of defense before the network boundary
• Canary honeypots — "prove it works" not "trust it works." Plant format-valid fake secrets and verify they're caught
• Local-only, deterministic, no ML — no cloud dependency, no probabilistic scoring, no telemetry. Runs offline, gives the same answer every time
• One command — pastewatch-cli launch claude and every layer is active. No manual setup, no env vars, no second terminal

What Pastewatch Does

Pastewatch started as a clipboard monitor — scan before paste, replace secrets with placeholders. It evolved into a full secret protection stack for AI agent workflows:

... View full README on GitHub