◉CLAUDE LABJP
●2.1.302 — Fork subagents are now on by default in claude -p, the Agent SDK and the desktop app. Turn them off with CLAUDE_CODE_FORK_SUBAGENT=0 (10/16)●2.1.299 — Conversations over 200K tokens left idle about 54 minutes get compacted; MCP allow rules now match only the server they name●SONNET 4.5 — Retires on the Claude API on 11/30, 43 days left. Migrate to Sonnet 5.5●WINDOWS — Reports say hooks break silently only on Japanese-locale Windows; check the character encoding first●FAST MODE — Opus 5.5 fast mode is out of research preview and no longer needs the beta header (10/15)●NEW — I Put a Ten-Line Promise File at the To…●2.1.302 — Fork subagents are now on by default in claude -p, the Agent SDK and the desktop app. Turn them off with CLAUDE_CODE_FORK_SUBAGENT=0 (10/16)●2.1.299 — Conversations over 200K tokens left idle about 54 minutes get compacted; MCP allow rules now match only the server they name●SONNET 4.5 — Retires on the Claude API on 11/30, 43 days left. Migrate to Sonnet 5.5●WINDOWS — Reports say hooks break silently only on Japanese-locale Windows; check the character encoding first●FAST MODE — Opus 5.5 fast mode is out of research preview and no longer needs the beta header (10/15)●NEW — I Put a Ten-Line Promise File at the To…
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All (907)◉ Claude AI (147)⟐ Claude Code (381)◈ Cowork (72)⬡ API & SDK (307)
⬡ API & SDK/2026-06-16Advanced

Confirm Your Model Actually Responds Before a Scheduled Run Begins

A model you configured can be gone before your nightly job even wakes up. Tell retirement, withdrawal, and regional restriction apart with a single startup probe, then rewrite the run config to an eligible model — with complete, working TypeScript.

⬡ API & SDK/2026-06-16Advanced

PII Masking for Claude API Lives or Dies on the Ledger — Restore, Encrypt, Measure

The hard part of masking PII before Claude API isn't detection — it's operating the token ledger you restore from. Encrypted storage, multi-instance sharing, and a daily leak-rate loop, with working code.

⟐ Claude Code/2026-06-16Intermediate

Two Days Into the Billing Change: How Far My Headless Costs Drifted From the Estimate

On June 15 the billing change moved headless execution onto separate monthly credits. Two days in, I broke down cost per pipeline stage and found one stage running at roughly double my estimate. Here is how I measured it, and why I moved one stage back to my subscription.

⬡ API & SDK/2026-06-15Advanced

On the day the billing change took effect, I added per-stage cost metering to my headless runs

The June 15 billing change moved headless runs and agent delegation onto monthly credits. Here is a thin metering layer that records token usage per stage tag from response.usage and emits a daily cost report, with working code.

⬡ API & SDK/2026-06-15Advanced

Centralizing the anthropic-beta Header So a Retired Beta Won't Kill Your Batch

Scattered anthropic-beta headers turn a beta retirement or GA graduation into a 400 that takes down an entire batch. A small capability registry, a startup preflight, and tiered fallback keep your pipeline running across feature generations.

◉ Claude AI/2026-06-15Advanced

When a Long-Running Agent's Context Quietly Decays — Budgeting and Compaction

An agent that runs all night gets sloppier by morning. The cause is dilution from accumulated context. Here is how to treat context as a budget, measure its decay, and keep it healthy with compaction — with working code and field notes.

⬡ API & SDK/2026-06-15Advanced

When a Model Disappears Without Warning: A State Machine for Retirement, Withdrawal, and Overload

A model can become unusable in hours for reasons that have nothing to do with a technical outage. This guide models three distinct flavors of 'unavailable'—retirement, withdrawal, and transient overload—as one availability state machine, with a router that keeps automated pipelines running. Working TypeScript and Python included.

⬡ API & SDK/2026-06-15Intermediate

Letting Claude Read Live Pages: Implementing web_fetch Without the Footguns

How to pull the actual text of official pages and PDFs straight into Claude's context with the web_fetch tool. Covers the URL-validation rule that trips everyone up, the settings that keep token costs down, and why fetch errors arrive as HTTP 200 — based on what I hit running it in production.

⟐ Claude Code/2026-06-14Advanced

Before Per-PR CI Burns Through Your Monthly Credits: A Three-Layer Guard for Claude Code GitHub Actions

From June 15, Claude Code GitHub Actions bills against non-rolling monthly credits. Run a review on every PR and you can drain the month in the first week. Here is a three-layer guard — when to run, how heavy one run can get, and making spend visible — with working workflows.

⬡ API & SDK/2026-06-14Advanced

Making Claude Agent SDK Tools Idempotent — Stopping Double Execution with Deterministic Keys and an Outbox

An implementation log for stopping a Claude Agent SDK retry or session resume from processing the same payment twice. Three patterns — deterministic idempotency keys, an outbox, and a lightweight wrapper — with runnable code and production metrics.

⟐ Claude Code/2026-06-14Intermediate

Finding and Installing Claude Code Plugins from a Marketplace — Read What's Inside Before You Trust It

A practical walkthrough for discovering and installing Claude Code plugins from a marketplace. Beyond the /plugin commands, it covers how to read the bundled contents before you install, and how to choose between User and Project scope.

⟐ Claude Code/2026-06-14Advanced

A SubagentStop Hook That Grades Subagent Output and Sends It Back to Be Redone

When a Claude Code subagent occasionally returns rule-breaking work, a SubagentStop hook can grade it automatically and ask for a redo. Here is a working setup with code and field notes.