Swap one block on a page without resending the page

Long pages are where full-page rewrites go wrong. You want one section changed, the old media and text pair in the middle of the services page, and the usual way an agent does that is by sending the whole page back with the change folded in. Every other block rides along on that trip, which is a lot to trust for one section.

Replace block changes one block, picked by its position, and leaves the rest of the page out of the write. This recipe reads the page, agrees on the block with you, and swaps only that one.

On our [Services] page (id [57]) I want to replace one section. It is the
[media and text block about consulting], somewhere in the middle.

Read the page as raw block markup and list the top-level blocks in order,
with their position and block name, so we agree which one it is.

The replacement is a [core/group] block holding [a heading, a short
paragraph and a button to /contact/]. Check that every block you plan to
use is registered on this site, and read the attributes it accepts, so
the markup is valid.

Show me the current block and the exact new markup side by side. Do not
save until I say go. When I do, replace only that block, passing the
block name you expect at that position so the call refuses if the page
has changed. Keep the old block markup in your reply, and tell me about
any content warnings the write returns.

Why this is safe to run

The page read and both block type reads change nothing, and they come first. You agree on the exact block by position and name, and you see the exact markup that will take its place, before anything is saved.

The write is one Replace block call. The plugin leaves the other blocks’ parsed attributes and HTML as they were, and passing the expected block name means a page that changed since the read is refused, not overwritten. If the page’s existing markup cannot be saved back cleanly, for example a block with broken attribute JSON, the call refuses too, and Update post is the tool for that page. Replace block is off until you enable it, it is checked against the edit access of the user the agent is bound to, it lands in the Activity Log, and with revisions on the page history can restore the earlier version.

Not sure what the page is made of yet? Run inspect a page’s block structure first.

Already connected? You do not have to paste this. Ask your agent for the “swap one block on a page” recipe, or describe the section you want replaced, and it runs the same read-first flow on your own site.