Make Claude Fable 5 the default Claude model#462
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Switch the no-flag claude-code default from claude-opus-4-8 to claude-fable-5 (Anthropic's new Mythos-class GA model). - claude-app-wrapper.py: DEFAULT_CLAUDE_MODEL -> claude-fable-5 (the functional default used when CLAUDE_MODEL is unset) - runtime_control.py: per-message header default -> fable; add a 'fable' alias and keep 'opus' as an explicit opt-back to claude-opus-4-8; --sonnet/--haiku untouched - update the 2 tests that pinned the old default
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What
Switches the no-flag
claude-codedefault model fromclaude-opus-4-8toclaude-fable-5— Anthropic's newly-released Mythos-class GA model.Changes
services/sandbox/claude-app-wrapper.py:DEFAULT_CLAUDE_MODEL → claude-fable-5— the functional default theclaudeCLI runs with whenCLAUDE_MODELis unset.services/api/api/runtime_control.py: per-message header default →fable; added afablealias and keptopus → claude-opus-4-8as an explicit opt-back.--sonnet/--haikualiases untouched.Scope
Only the no-flag default changes.
--opus,--sonnet,--haikuare unaffected;--opusremains the way to pin Opus 4.8.Tests
pytest tests/test_claude_app_wrapper.py tests/test_workflow_engine_title.py→ 28 passed.