Claude Marshmallow, Melon EAP Leaks Surface

The leak is interesting evidence of Anthropic’s rapid checkpoint testing, but it is not a product launch. Developers should treat the names as unverified infrastructure traces until official documentation appears.

• –“EAP” likely signals early-access or evaluation builds, but could also identify routing aliases or internal experiments.
• –Community feedback favors Marshmallow, though no reproducible benchmarks or model card support the claims.
• –Reports of a live `claude-marshmallow-ht-eap` variant are stronger than simple model-list sightings, yet still lack first-party confirmation.
• –The codenames do not establish that Opus 5.1 or Fable 5.1 exists.
• –Avoid building against leaked identifiers; wait for official API IDs, pricing, limits, and safety documentation.