Fennec
- Entity ID:
ent-20260419-eaeac0c992cf - Type:
concept - Scope:
shared - Status:
active - Aliases: fennec-latest, Opus 4.6 predecessor
Description
Internal Anthropic codename for the predecessor of Opus 4.6; fennec-latest migrated to opus in production. Part of the animal-codename scheme (Tengu, Capybara, Fennec, Numbat).
Key claims
- Model codename map complete: Fennec → Opus 4.6 predecessor; Numbat unreleased
- Mythos Preview produces 181 working Firefox exploits vs Opus 4.6's 2
- Same Opus 4.6 scores 16pp lower under Claude Code harness vs Cursor harness
Relations
- Fennec --[contained_in]--> Model Codenames
- Firefox 148 Exploit Benchmark --[related_to]--> Fennec
- Harness Underperformance Gap (77% vs 93%) --[observes]--> Fennec