---
title: "Start here"
description: "One page per reader, whether you write a pack, build a runtime, adopt packs in a host or are weighing HCP, plus one-step setup for your agent."
canonical: https://harnesscontextprotocol.io/docs
---

# Start here

> One page per reader, whether you write a pack, build a runtime, adopt packs in a host or are weighing HCP, plus one-step setup for your agent.

<section className="docs-hero">
<h1>Documentation</h1>
<p className="docs-hero-lead">A Harness Pack is three files that describe a CLI you already ship, so a person, an agent and a product UI all run it as one governed command. Pick the page for what you do and start there.</p>
</section>

## Choose your path

<Cards>
  <Card title="Build a pack" href="/docs/packs">
    You ship a CLI and want agents, people, and product UIs to run it as one governed command.
  </Card>
  <Card title="Implement a runtime" href="/docs/runtimes">
    You build the product that loads packs, enforces grants, and runs them under your own auth.
  </Card>
  <Card title="Adopt in a host" href="/docs/hosts">
    You make an agent product and want it to install packs as easily as it adds an MCP server.
  </Card>
  <Card title="Evaluate HCP" href="/docs/introduction/what-is-hcp">
    You want to know what HCP is, which problem it solves, and where it sits beside Agent Skills and MCP.
  </Card>
</Cards>

## Set up your agent

Every host gets one Skill and one tool named `hcp` that reaches every pack you
activate, or your agent can do the whole setup from
[one prompt](/docs/quickstart#let-your-agent-do-it).

<HostSetup />

## Look something up

[Concepts](/docs/concepts) explains the objects every call passes through, and
[Design principles](/docs/introduction/design-principles) the twelve laws behind
them. For lookups, the [CLI reference](/docs/reference/cli) has every `hcpx`
command and exit code, [Manifest fields](/docs/packs/manifest) every
`surface.json` field, [Pack classes](/docs/packs/best-practices#pack-classes)
five shapes to copy, the [glossary](/docs/reference/glossary) every term, and
the [specification](/docs/specification) what packs, runtimes and hosts must do.

## For agents

Every page has a Markdown twin: append `.md` to the URL or send
`Accept: text/markdown`. The full corpus is at [`/llms.txt`](/llms.txt) and
[`/llms-full.txt`](/llms-full.txt), search at `/api/v1/search?q=`, and a
read-only MCP server at `/mcp` offers `list_pages`, `search`, and `get_page`.

## Sitemap

- [Documentation](https://harnesscontextprotocol.io/docs)
- [Packs](https://harnesscontextprotocol.io/packs)
- [Glossary](https://harnesscontextprotocol.io/docs/reference/glossary)
- [llms.txt](https://harnesscontextprotocol.io/llms.txt)
- [llms-full.txt](https://harnesscontextprotocol.io/llms-full.txt)
- [OpenAPI](https://harnesscontextprotocol.io/openapi.json)
- [MCP](https://harnesscontextprotocol.io/mcp)