Secret

Secret

Let coding agents use your credentials without reading them.

A local credential CLI, a names-only MCP server, and a guard hook for coding agents.

Agents see key names, labels and paths, never values through the names-only interface. The CLI passes selected values directly to programs; the guard denies known store-reading operations.

How it works

1. The agent asks for a credential by key name, not its value.
2. secret hands the selected value directly to the program's environment.
3. secret run redacts loaded literal values from stdout and stderr.

Accident prevention, not a sandbox.

Install

Install or update the Secret CLI to the latest release.

Linux/macOS:

curl -fsSL https://raw.githubusercontent.com/avhn/secret/v0.6.0/install.sh | sh

Windows PowerShell:

irm https://raw.githubusercontent.com/avhn/secret/v0.6.0/install.ps1 | iex

No GitHub account or gh is needed; rerunning updates the installation.

See pins, paths and verification.

Use it

In your own terminal, stash a value with a hidden prompt. Agents can use show and run, but must never enter or retrieve values. These are illustrative paths:

secret stash ~/.secrets.env API_TOKEN

secret show ~/.secrets.env secret run -f ~/.secrets.env --key API_TOKEN -- ./deploy.sh

Register names-only MCP using the installed executable's concrete absolute path and an exact human-approved store reference. Do not discover or read stores:

claude mcp add --transport stdio --scope user secret -- "/ABSOLUTE/INSTALL DIR/secret" mcp --store "file:/ABSOLUTE/STORE DIR/STORE.secret"

Reconnect the client and verify list/show/diff/health. See Windows equivalents and client setup.

Use it to launch other MCP servers

For a human-configured client launcher, exec supplies selected values without filtering the server's stdio. It works on macOS, Linux and Windows; Windows long-lived exec shipped in v0.3.4. -f takes a plain store path, not file::

"/ABSOLUTE/INSTALL DIR/secret" exec -f "/ABSOLUTE/STORE DIR/.secrets.env" --key OPENPROJECT_API_TOKEN -- uvx openproject-ce-mcp@0.4.1

This is not the names-only server or an agent retrieval route. Output is unfiltered and can disclose values. Review the server and configure this yourself; see client JSON, Windows paths and shutdown limits.

Next steps

• Set up clients, including the Claude Desktop MCPB and MCP Registry name io.github.avhn/secret; see the release status for the currently published record.
• Verify, update or roll back, with explicit Bash rollback at compat/secret.
• Windows support and limits.
• Security model and reporting.

Guard hook

The optional Claude Code and Codex plugins install the Bash guard and agent skill, not an MCP registration. Codex requires explicit hook trust in /hooks, including re-trust after changes. Install the protective ripgrep config and review the manual-hook instructions there. Go hooks remain inactive; installation and synthetic tests do not prove host fail-closed protection.

More workflows

See detailed usage, providers, labels, operator commands and templates, encrypted age stores, inactive 1Password scaffolding and pass stores.

Security limits

Literal redaction does not catch base64, URL encoding, substrings or other transformations. The guard cannot contain a determined agent, arbitrary child behavior or tools it never sees, including MCP search tools. Metadata can reveal names, labels, paths and provider account IDs. Treat this as one layer, not the boundary. Read the full threat model.

Development

See CONTRIBUTING.md for synthetic tests and PR guidance, AGENTS.md for agent rules and ROADMAP.md for milestones.

License

GPL-3.0-or-later, copyright Mert Dede.