Goals

• Create a 1:1 association between a Frame domain and an fid that can be lazily verified.
• Minimize number of tools and network requests required to verify a domain association.
• Allow for future extensions to domain verification.

Creating a domain association

To associate a frame domain with an FID, the frame developer must:

Produce a signed ERC-191 message from a verified address associated with the FID:

const sig = await account.signMessage({ 
  message: "fid=3621 domain=yoink.terminally.online" 
});

Add an fc:frame:domain_association tag to frame metadata:

<meta property="fc:frame:domain_association" content="3621:0xabcd...:0x1234..." />

Where the content attribute is in the form <fid>:<addr>:<sig>, and:

• <fid> is the user’s FID
• <addr> is the connected address signing the message
• <sig> is the hex-encoded ERC-191 signature.

Verifying a domain association

To verify a domain association for an FID, the relying party must:

1. Parse the fid, address and signature from the Frame metadata tags.