# Swarm

Use `bzz://<reference>[/path]`. Support direct file references and manifest paths,
including feed manifests. Reject URI queries and fragments.
Apply the [shared retrieval rules](/implementers/proof-retrieval).

## Retrieval

1. Validate the reference using Swarm's reference format. An encrypted reference
   must include the complete key-bearing reference, not just its content address.
2. Read the referenced data through a verifying Bee node or a client that checks
   the returned chunks and their links.
3. For a manifest, resolve the requested path to one file. An empty path may use
   its declared index entry. Do not use a website error page as a proof.
4. For a feed manifest, validate the signed feed update and follow the resulting
   reference. Bound lookups and detect loops.
5. Reconstruct and, where required, decrypt the file. Apply the proof format and
   envelope size rules to the resulting bytes.

A remote gateway's decoded file alone does not establish the reference-to-file
binding. Use an explicitly configured verifying node or validate the underlying
content yourself. Public descriptors containing decryption keys do not make the
proof confidential.

See Swarm's [upload and download guide](https://docs.ethswarm.org/docs/develop/upload-and-download/),
[encrypted references](https://docs.ethswarm.org/docs/develop/tools-and-features/store-with-encryption/),
and [feeds](https://docs.ethswarm.org/docs/develop/tools-and-features/feeds/).

## Caching

Cache immutable content by its full reference and path. A feed is mutable:
refresh it before reusing a result, and do not describe a previously observed
update as necessarily the latest. Proof expiry and current ENS state still apply.