Update a signature
Rename it, rewrite its HTML, or change what it is the default for.
Runs the real call on your workspace.
PATCH /signatures/{id}
Rename it, rewrite its HTML, or change what it is the default for.
Example
Needs settings:write. Send only what changes.
curl -X PATCH "$OE/signatures/sig_8f2c1a9b7d3e4f60a1b2c3d4" -H "$AUTH" -H "Content-Type: application/json" \ -d '{ "isDefault": true }'{ "object": "signature", "id": "sig_8f2c1a9b7d3e4f60a1b2c3d4", "address": "[email protected]", "name": "Short", "html": "<p>Ada<br />Acme Ltd</p>", "isDefault": true, "isReplyDefault": true, "createdAt": "2026-10-12T09:14:03.117Z", "updatedAt": "2026-10-12T09:14:03.117Z"}isDefault: true makes it the signature of new mail from its address in place of the one that was. isDefault: false takes that away when this signature held it, so new mail from the address goes out with no signature until another one is chosen. isReplyDefault does the same for replies and forwards.
Send any of name, html, isDefault and isReplyDefault. A body with none of them is a 422, and a new name another signature of the address already has is a 409 signature_name_taken.
A message that is already scheduled picks up the new HTML when it goes out.