"Change template" answered "no slide layout" for 28 of the 41 presentations
in production: the theme lived only inside the deck JSON, and a presentation
whose deck reply failed twice and fell back to markdown slides had nowhere
to keep one. The theme is a column now, written at generation and by the
picker, and the markdown slide builder carries it to the same renderer field
a designed deck uses. A deck's own theme field is kept in step. Articles are
the only thing refused — they have no slides.
A deck reply that fails to parse is logged with its first 240 characters, so
the next "the reply was not a deck" can be read rather than guessed at.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Dv6sqaY6Vq3ChZHMem3cnU
0163d40811