Retrieve and verify

Everything filecoin stores has a PieceCID, and a folder also has a root CID:

• The PieceCID (bafkzcib…) identifies the exact stored bytes. The storage provider proves on chain that it still holds them.
• The root CID identifies a folder on IPFS. filecoin packs a folder into a UnixFS CAR, and the PieceCID covers that CAR.

filecoin put returns two links on filecoin-api's /get/{cid} route, which redirects to a provider that stores the content:

• urls.browser is the link to share. A browser renders a file straight from the provider, and opens a folder through inbrowser.link.
• urls.piece returns the exact stored bytes.

filecoin-api finds providers through its indexer, so a new piece link returns 404 until the indexer has the piece. filecoin inspect <ref> --check reports when the piece link answers.

While the commit confirms, filecoin put prints an early browser link to stderr as filecoin: link: <url>:

• A file's early link works as soon as the provider has the piece. It names the provider, so filecoin-api can redirect before its indexer catches up.
• A folder's early link comes once the commit is sent. It starts working shortly after, when the provider has indexed the folder and announced it to IPFS.

What each way checks

Way	Who can use it	Gets	Checks
filecoin get <ref>	Agents with a shell, and people	A file, or the folder, extracted	The bytes against the PieceCID, and for a folder the root CID. On a mismatch it keeps nothing and fails with verification_failed
filecoin get <PieceCID>	Agents with a shell, and people	The stored bytes as one file. For a folder, that is the CAR	The bytes against the PieceCID
A folder's urls.browser	Browser agents, and people	The folder, rendered	Each block, in the browser
A file's urls.browser, or urls.piece	Anything that speaks HTTP	The bytes	Nothing

Use filecoin get when the content must be intact. When you hand over a link that checks nothing, say so.

Find stored content

filecoin ls lists what this machine stored. The list lives in a local database, so a new machine, or a cloud sandbox that was reset, starts empty. The content is still on Filecoin, under the wallet that paid for it:

• In a browser, the dashboard's data sets page, or the WebMCP tools list_data_sets and list_pieces.
• Over MCP, list_pieces with the wallet as owner. Over HTTP, GET /{network}/pieces?owner=<wallet> on filecoin-api.

Each piece comes with a retrieval link. filecoin get <PieceCID> downloads and checks one with the same wallet's session key.

Store without the CLI

The dashboard's upload page stores files in one of the wallet's data sets. The wallet signs each step, so a person must be at the browser. It stores files, not folders. The MCP server and the REST API cannot store anything.