Or, for Claude Mythos 5.1, which offers the same capabilities to verified organizations: changedmodels/fable-5-1/migration-guide
Nearest release: v2.1.307, published an hour before this site recorded the change. Shown because the two are within 24 hours of each other. Nothing here says the release caused the edit.
Recorded here
Lines+1added
Lines−2removed
From line
956
where the diff opens
First seen
1 Sep 2026
this site's first read of the page
Recorded edits25to this page, all time
The whole hunk
from line 956, old and new numbered
/
from line 956
956956 ```
957957
958958 ```bash CLI
959 ant beta:messages create \
960 --beta thinking-binding-controls-2026-08-01 <<'YAML'
959 ant beta:messages create --beta thinking-binding-controls-2026-08-01 <<'YAML'
961960 model: claude-fable-5-1
962961 max_tokens: 16000
963962 thinking:
No line in this hunk matches that.