madeye

Sealgate — AI skill for Claude Code

AI community

Protect sensitive prompt spans with trusted LLM detection and local authenticated encryption before using Claude Code.

How to install Sealgate

This entry records only its repository, not the path inside it, so there is no exact command to give. Open madeye/sealgate and copy the folder into ~/.claude/skills/, or the file into ~/.claude/agents/.

What Sealgate does

Protect sensitive prompt spans with trusted LLM detection and local authenticated encryption before using Claude Code.

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README

sealgate

**[Read the website and getting-started guide →](https://madeye.github.io/sealgate/)**

Encrypt sensitive text before Claude Code sends it remotely. `sealgate claude` keeps Claude's native terminal interface and subscription login, with a local gateway that inspects complete model requests and an OS sandbox (the macOS sandbox, or Docker on Linux). Linux tools have direct network access outside SEALGATE; macOS blocks other network traffic by default. Your configured **trusted detection provider**, such as local vLLM, identifies sensitive spans; Node encrypts them with a local AES-256-GCM key.

For narrower workflows, `sealgate protect` prints a protected prompt for pasting and `sealgate chat` offers a prompt-only terminal wrapper. The companion plugin supplies a reminder; it cannot intercept requests by itself.

This is conventional authenticated encryption, **not homomorphic inference**. Claude can use the surrounding text but cannot understand encrypted values.

flowchart LR
    U[Native Claude and local tools] -->|Isolated local relay| G[SEALGATE gateway]
    G -->|Original request text| P[Trusted LLM or local vLLM]
    P -->|Sensitive spans| G
    K[Local encryption key] --> G
    G -->|Protected request and subscription OAuth| A[Anthropic]
    A -->|Streamed response| G
    G --> U

See the [gateway guide](docs/gateway.md) for the native launcher and network boundary, [how it works](docs/how-it-works.md) for the detection, encryption, and decryption steps, and [the security model](docs/security.md) for trust boundaries and limitations. The instructions below cover installation and configuration.

Install

Requires Node.js 22 or later. The enforced `sealgate claude` launcher additionally requires the native `claude` binary on PATH and either macOS (ARM64 or x86-64, using the built-in `sandbox-exec` sandbox) or Linux ARM64/x86-64 with a local Docker daemon. Manual preprocessing and the older chat wrapper also work on WSL. The project