> ## Documentation Index
> Fetch the complete documentation index at: https://filepacks.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Overview

> What lives inside a .fpk artifact and why the format is designed for trustworthy review.

The public filepacks artifact is a deterministic `.fpk` archive.

It contains:

* `manifest.json` as the first entry
* payload files under `payload/`

The current public OSS surface uses generic `format_version: 1` manifests only.

## What the artifact gives you

A `.fpk` file is designed to be:

* **portable** as one file
* **inspectable** through the manifest
* **verifiable** against the payload
* **comparable** against another artifact with deterministic rules

## What's inside a `.fpk` file

A `.fpk` artifact has a fixed layout:

```text theme={null}
manifest.json          ← canonical file inventory, always first
payload/results.json   ← payload file
payload/summary.txt    ← payload file
...
```

`manifest.json` records the artifact name, file count, total size, per-file hashes, and a payload digest. Those values are what `inspect`, `verify`, and `compare` operate on — no payload extraction needed for most operations.

## Why manifest-first packaging matters

The format is the trust anchor for the current OSS release:

* the artifact is portable as one file
* the manifest is the canonical file inventory
* verification is local and deterministic
* comparison is manifest-driven, not filesystem-dependent

Because the format is deterministic, the archive digest is a meaningful identity. The same directory contents produce the same `.fpk` bytes, making the digest stable across machines and time.

## Public artifact guarantees

* `.fpk` is a POSIX tar archive
* `manifest.json` must appear exactly once
* `manifest.json` must be the first entry
* entries outside `manifest.json` and `payload/` are invalid
* payload entries must be regular files
* directory entries must not be emitted
* payload paths must be normalized relative paths

## Which artifact page to read next

| If you need...                             | Read                                  |
| ------------------------------------------ | ------------------------------------- |
| field-by-field manifest details            | [Manifest](/artifacts/manifest)       |
| archive layout and path rules              | [Format](/artifacts/format)           |
| determinism guarantees and why they matter | [Determinism](/artifacts/determinism) |

## See also

1. [Manifest](/artifacts/manifest)
2. [Format](/artifacts/format)
3. [Determinism](/artifacts/determinism)