# Build with Specs. Code with Context.

> Archcore keeps project decisions, rules, specs, and plans in Git and makes them available to AI coding agents.

Archcore is a git-native context layer for AI coding agents. It keeps specs, architecture, decisions, rules, and plans in your repository and makes that project context available as your agent works.

Start with a decision or rule your agent needs for its next task. Record it in `.archcore/`, review the document, and retrieve it in a later session. The same project documents are available across your connected agents.

## Start using Archcore

[Section titled “Start using Archcore”](#start-using-archcore)

1. [Install Archcore](/start/install/) and connect your coding agent.
2. [Follow the quick start](/start/quick-start/) to record and reuse project context.
3. [See what to expect](/start/what-to-expect/) during a session, including what happens automatically.

## Use it in your project

[Section titled “Use it in your project”](#use-it-in-your-project)

| Your task                                            | Where to go                                       |
| ---------------------------------------------------- | ------------------------------------------------- |
| Record a decision, plan a change, or review a branch | [Commands and examples](/guides/commands/)        |
| Add Archcore to an agent or your own harness         | [Connect your agent](/guides/connect-your-agent/) |
| Use Archcore alongside another tool                  | [Integrations](/guides/integrations/)             |
| Diagnose a missing tool, hook, or document           | [Troubleshooting](/guides/troubleshooting/)       |

## Understand the model

[Section titled “Understand the model”](#understand-the-model)

Archcore supports spec-driven development and context engineering. Specs describe intended behavior; project context also includes the decisions, constraints, and rules behind that behavior.

[Why Archcore](/concepts/why-archcore/) explains the design choices and tradeoffs. [Project context](/concepts/project-context/) explains how documents, categories, and relations fit together.

## Next steps

[Section titled “Next steps”](#next-steps)

[Install Archcore](/start/install/) to begin, or open the [CLI command reference](/cli/commands/) for a specific terminal task.