●FORK — Claude Code 2.1.212 changes what /fork does: it copies your conversation into a new background session with its own row in claude agents, so you can keep working. The old in-session subagent is now /subtask●LIMITS — WebSearch calls are now capped at 200 per session by default, and subagent spawns get the same 200 ceiling, so a runaway search or delegation loop stops on its own●MCPBG — MCP tool calls running past two minutes now move to the background automatically, keeping the session usable. Tune the threshold with CLAUDE_CODE_MCP_AUTO_BACKGROUND_MS●PLANFIX — Fixed plan mode auto-running file-modifying Bash commands such as touch and rm without a permission prompt or an SDK canUseTool callback●SONNET5 — Claude Sonnet 5 is running on introductory pricing of $2 per million input tokens and $10 per million output. After August 31 it moves to $3 and $15●IPO — Bankers are reportedly lining up investor meetings for Anthropic ahead of a possible public listing as soon as October●FORK — Claude Code 2.1.212 changes what /fork does: it copies your conversation into a new background session with its own row in claude agents, so you can keep working. The old in-session subagent is now /subtask●LIMITS — WebSearch calls are now capped at 200 per session by default, and subagent spawns get the same 200 ceiling, so a runaway search or delegation loop stops on its own●MCPBG — MCP tool calls running past two minutes now move to the background automatically, keeping the session usable. Tune the threshold with CLAUDE_CODE_MCP_AUTO_BACKGROUND_MS●PLANFIX — Fixed plan mode auto-running file-modifying Bash commands such as touch and rm without a permission prompt or an SDK canUseTool callback●SONNET5 — Claude Sonnet 5 is running on introductory pricing of $2 per million input tokens and $10 per million output. After August 31 it moves to $3 and $15●IPO — Bankers are reportedly lining up investor meetings for Anthropic ahead of a possible public listing as soon as October

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cache-control

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claude-api² prompt-caching² cost-optimization² scheduled-jobs¹ ttl¹ production¹

⬡ API & SDK/2026-06-24Advanced

My Morning Batch Was Missing the Prompt Cache Every Time — Warming Cadence and the Break-Even Math for the 1-Hour TTL

Jobs that run a few hours apart cold-miss the prompt cache even with a 1-hour TTL. Here is how to back out the right warming interval from the TTL, and how to write the break-even formula that decides whether warming pays off — with numbers from a four-site daily generation pipeline.

⬡ API & SDK/2026-05-29Advanced

Splitting Claude API prompt cache into 5m and 1h tiers — separate TTLs cut cost and stabilize ops

Anthropic's cache_control supports two TTLs: 5 minutes and 1 hour. Splitting them into a two-tier layout — 1h for static system/tools, 5m for variable few-shot — meaningfully changed both my costs and my on-call life. Here's the design with the numbers I observed.