Anthropic AI Updates: June 15, 2026

1. Claude Sonnet 4 and Opus 4 Retire From the API Today

Anthropic. Effective June 15, 2026, Anthropic has retired claude-sonnet-4-20250514 and claude-opus-4-20250514 from the Claude API, ending a deprecation period that began April 14. Any API calls referencing these model IDs will now return an error. Anthropic recommends migrating claude-sonnet-4-20250514 workloads to claude-sonnet-4-6 and claude-opus-4-20250514 workloads to claude-opus-4-8, both of which remain active. Teams that have not yet migrated can audit usage via the Claude Console Usage export to identify affected API keys. Source

2. Agent SDK and Headless Claude Code Billing Splits Off Subscription Plans

Anthropic. Also effective June 15, Anthropic is separating Agent SDK and claude -p (non-interactive) usage from subscriber plan pools. Claude Agent SDK, headless Claude Code, Claude Code GitHub Actions, and third-party agents that authenticate through the Agent SDK will now draw from a dedicated monthly dollar credit billed at standard API rates rather than counting against subscription limits. Credits are sized to match each plan — $20 per month for Pro, $100 for Max 5x, $200 for Max 20x, and $20 or $100 per seat for Team plans — and do not roll over. Interactive terminal Claude Code sessions and claude.ai chat are unaffected. Users needed to claim their credit via email before today’s cutover; without claiming, the programmatic allowance is not activated. Source

3. Claude Mythos Preview Retirement Scheduled for June 30

Anthropic. Anthropic has posted a notice on its model deprecations page that claude-mythos-preview will be retired on June 30, 2026, giving developers two weeks to migrate to claude-mythos-5. Claude Mythos 5 is the generally available successor to the preview and sits above the Opus tier in Anthropic’s capability hierarchy. The retirement applies to the Claude API, Claude Platform on AWS, and Microsoft Foundry; Bedrock and Vertex AI follow their own schedules. Source