◉CLAUDE LABJP
●CLI — Claude Code v2.1.259 landed on September 2. It is a dense release focused on org-wide configuration, unattended runs, and permissions — the most practically useful one this week●MCP — A new managedMcpServers setting lets an organization push HTTP/SSE MCP servers to every user. At the same time allowedMcpServers narrowed in scope, so an allowlist no longer filters managed servers out●HEADLESS — The new --permission-prompts none flag denies anything that would prompt, while the active permission mode, auto included, keeps making its own calls. Useful for anything you run unattended●SECURITY — Bash Read() deny rules had gaps: files passed as option values such as --ignore-revs-file=.env, and compounds like cd DIR && cat FILE, slipped past them. Both are now covered●SLACK — Claude Tag no longer judges messages one at a time. It reads the whole channel, along with its memory and your standing instructions, and is roughly 30% better at staying out of conversations●LEARN — Claude Academy is open. It is a free learning hub built on the 4D AI Fluency Framework that Anthropic uses to onboard its own team, with completion tracked in your Claude profile●CLI — Claude Code v2.1.259 landed on September 2. It is a dense release focused on org-wide configuration, unattended runs, and permissions — the most practically useful one this week●MCP — A new managedMcpServers setting lets an organization push HTTP/SSE MCP servers to every user. At the same time allowedMcpServers narrowed in scope, so an allowlist no longer filters managed servers out●HEADLESS — The new --permission-prompts none flag denies anything that would prompt, while the active permission mode, auto included, keeps making its own calls. Useful for anything you run unattended●SECURITY — Bash Read() deny rules had gaps: files passed as option values such as --ignore-revs-file=.env, and compounds like cd DIR && cat FILE, slipped past them. Both are now covered●SLACK — Claude Tag no longer judges messages one at a time. It reads the whole channel, along with its memory and your standing instructions, and is roughly 30% better at staying out of conversations●LEARN — Claude Academy is open. It is a free learning hub built on the 4D AI Fluency Framework that Anthropic uses to onboard its own team, with completion tracked in your Claude profile
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Claude Haiku 3 Deprecation — Migrate by April 19, 2026

Claude HaikudeprecationmigrationAPI

Deprecation Notice

Anthropic has announced that Claude Haiku 3 (claude-3-haiku-20240307) will be retired on April 19, 2026. After this date, API requests to this model will return errors.

Who Is Affected

Developers using claude-3-haiku-20240307 in API calls. Claude.ai users are automatically switched to newer models and are not affected.

Migration Target

The successor model is Claude Haiku 4.5 (claude-haiku-4-5-20251001).

Key Differences

  • Context window: 200K tokens (unchanged)
  • Max output: 64K tokens (up from 4K in Haiku 3)
  • Extended Thinking: Supported (not available in Haiku 3)
  • Pricing: Input $1 / Output $5 per million tokens (higher than Haiku 3 but justified by performance improvements)

Migration Steps

Simply change the model ID in your API code.

# Before
model="claude-3-haiku-20240307"
 
# After
model="claude-haiku-4-5-20251001"
# Or use the alias
model="claude-haiku-4-5"

Things to Watch

  • Haiku 4.5 has much larger max output, so review your max_tokens settings
  • Pricing has changed, so update your cost estimates
  • Enabling Extended Thinking incurs additional costs

Summary

Complete your migration by April 19, 2026. With significantly improved performance, Haiku 4.5 offers substantial benefits.