# Sparsh
> A direct, encrypted wire between two paired keys. Files, messages and MCP, with no server that can read a byte.
> Source: https://jvoltci.github.io/sparsh/docs/

Two devices, one channel, nothing in between that can read it.

Open Sparsh in a browser and send a file. Install the CLI and an agent can do
the same thing headlessly. Grant one pairing the right, and an agent on one
machine can call the tools on another, with no port, no VPN and no account.

A round trip on a warm channel is **0.21** ms, measured, on
loopback. Every number on this site is read from the ledger the test harnesses
write, never typed.

## Start

The browser side needs nothing at all: [open the app](../) on both devices.
For the CLI, today, run it from the repository:

```bash
git clone https://github.com/jvoltci/sparsh && cd sparsh/frontend && npm install
```

Then, on the device that will be reached:

```bash
npm run peer -- invite
```

Open the link it prints on the other device. That is the pairing, and it is the
only step a human has to do.

## For an agent

```bash
claude mcp add sparsh -- sparsh mcp-tools
```

Four tools arrive: `sparsh_status`, `sparsh_devices`, `sparsh_send` and
`sparsh_inbox`. Tools return paths, never bytes. There is no pairing tool,
deliberately: an agent must never pair itself.

## Hand this page to your agent

Every page here is also markdown at the same address with `.md` on the end, and
the whole site is in [llms.txt](/llms.txt). Nothing has to be scraped.

> Sparsh is a peer-to-peer transport for devices and agents. Read
> https://jvoltci.github.io/sparsh/docs/llms-full.txt for the full documentation,
> then answer using only what it says.

## What to read next

- [Install](/install) puts the CLI on a machine and pairs two devices.
- [Agents](/agents) is the MCP surface, local and remote.
- [Security](/security) says what is encrypted, by what, and what is not.
- [How it works](/how-it-works) is the handshake, the channels and the wire.
- [Performance](/performance) is every measured number with its instrument.