bitcoin/doc/release-notes-34672.md

IPC Interface

• BlockTemplate.submitSolution now returns reason and debug rejection details in addition to the boolean result. Clients must regenerate IPC bindings from the updated mining.capnp schema to use the new method. The previous @7 method now returns an error directing clients to update. (#34672)

• BlockTemplate.submitSolution now reports duplicate blocks as failures with reason="duplicate", matching Mining.submitBlock, instead of returning success for duplicate submissions. (#34672)