Anthropic Releases Claude Mythos 5 and Fable 5 with Guardrails (infosecurity-magazine.com)

• Anthropic releases Mythos 5 (frontier, restricted) and Fable 5 (public with guardrails).
• Guardrails redirect sensitive queries to Claude Opus 4.8 in <5% of sessions.
• Pricing: $10/M input, $50/M output tokens.
• Microsoft integrates Fable 5 into Foundry and GitHub Copilot.
• Experts caution guardrails may be insufficient against determined attackers.

"Anthropic announced Claude Mythos 5, a restricted-access frontier AI model, and Claude Fable 5, a guardrailed version for public use. Fable 5 redirects sensitive queries to a safer model in <5% of sessions. Pricing is half that of the Mythos Preview. Microsoft made Fable 5 available in Foundry. Cybersecurity experts expressed concerns about the sufficiency of guardrails."