Quickstart

Pick the path that matches what you are building (a pack, a runtime, or a host integration) and get to a working exec in minutes.

HCP has three kinds of participants. Each has its own ten-minute path.

Build a pack

You have a CLI or an API and want agents, humans, and UIs to run it as one governed command.

Implement a runtime

You are building the thing that loads packs, enforces grants, and executes, with the SDK or from scratch.

Adopt in a host

You ship an agent product and want native pack intake with the same ease as adding an MCP server.

Prerequisites

All three paths use the hcp CLI, which is itself the first pack. From the SDK repository:

git clone https://github.com/harnesscontextprotocol/hcp
cd hcp && bun install
alias hcp='bun ./packages/cli/src/hcp.ts'
hcp doctor --json

The first run creates $HCP_HOME (default ~/.hcp) and installs the hcp-cli bootstrap pack, so there is always a working pack to exec against.

{ "ok": true, "cli": "hcp", "protocol": "hcp", "version": 1, "sandbox": true, "installed": ["hcp-cli"] }

Set HCP_HOME to relocate the store. This is useful in CI, or to keep a project store separate from your personal one.

Two gold packs

Every quickstart uses the same two sample packs from examples/packs/. Copy the one closest to what you are building.

Pack	Class	What it proves
`transit`	Public read	Five closed read commands, no login, no secrets
`ledger`	Gated write	Installer family, `connect`, one read, and a `transfer` that fails closed without `--confirm`

Both are wrap packs over tiny demo binaries in examples/bins/. They are the fixtures for the conformance suite, so what they do is what the protocol promises.

What "done" looks like

Whichever path you take, you are finished when this proof script passes:

lint                                  → no issues
one Execute read                      → { ok: true, result: … }
one gated write without confirm       → { ok: false, error: "confirm required" }
the same write with confirm (mock)    → { ok: true }
availability                          → installed · activated · connected · executable

That script is how a pack demonstrates conformance. See Testing.