◉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…
ARTICLES

All Articles

All (907)◉ Claude AI (147)⟐ Claude Code (381)◈ Cowork (72)⬡ API & SDK (307)
◉ Claude AI/2026-05-21Intermediate

Three Weeks of Tuning AdMob Floor Prices with Claude in Chrome

Notes from three weeks of small daily floor-price adjustments across four iOS apps, with Claude in Chrome doing the dashboard rounds and me keeping the judgment calls.

⬡ API & SDK/2026-05-21Advanced

Forecasting Claude API token costs with ±10% accuracy from the first three days

A practical EWMA + seasonality decomposition model that forecasts month-end Claude API costs from only the first three days of token usage, with three-tier automated guardrails for prompt caching, model routing, and rate limiting.

⬡ API & SDK/2026-05-20Advanced

Resolving Tool Name Collisions When Bundling Multiple MCP Servers in the Claude Agent SDK

When the GitHub MCP and Linear MCP both expose create_issue, Sonnet 4.6 cannot tell them apart. This article covers the structure of MCP tool name collisions, a TypeScript reconciler implementation, and a measured correction: the schemaHash I originally published missed all five schema drifts I tested it against.

⟐ Claude Code/2026-05-20Intermediate

Claude Code Says 'All Tests Pass' but CI Goes Red — Designing Around Exit Code Pitfalls

Locally, Claude Code reports 'all tests pass.' You push it, and GitHub Actions turns red within minutes. The root cause is usually not Claude Code itself but how the shell and the test runner interpret exit codes. Here is a practical, experience-backed walkthrough.

⟐ Claude Code/2026-05-20Intermediate

Pruning Custom Subagents in Claude Code: After Six Months, Five Became Two

I built five custom subagents in Claude Code, ran them across six sites for six months, and ended up keeping only two. Here are the notes I took along the way — what worked, what didn't, and how I learned to write subagent descriptions that actually get called.

⬡ API & SDK/2026-05-20Advanced

Compressing Tool Results in Claude Agents — Aggregating Large Responses Without Bloating Context

When a database returns 8,000 rows, a scrape returns 200KB of HTML, or a file read returns several megabytes, dropping the raw payload into your Claude tool result wrecks both cost and quality. This guide presents a three-layer compression architecture — schema projection, summarization, and reference handles — with TypeScript examples from a production agent pipeline.

⬡ API & SDK/2026-05-19Advanced

Hierarchical Chat History Summarization with Claude API: A 3-Tier Design That Cut Tokens by 70%

Working TypeScript design for compressing long in-app chat histories into three tiers — recent turns kept verbatim, mid-range episodes summarized with Haiku 4.5, and long-range memory distilled to JSON by Sonnet 4.6. Includes seven weeks of production data showing input tokens down 70% and monthly API cost down from $480 to $145.

⟐ Claude Code/2026-05-19Intermediate

Why Claude Code's WebFetch Returns 403 or Empty Pages — and How to Fix It

When Claude Code's WebFetch returns a 403, or a 200 OK with the body mysteriously empty, there are really only four root causes worth checking. This walkthrough breaks them down — Cloudflare bot protection, client-side rendering, the allowed-domains gate, and stale caches — with the practical responses I use in production.

⬡ API & SDK/2026-05-19Advanced

Installing Safety Valves in Claude Agents: A Three-Layer Kill-Switch Design for Solo Operators

A design record from a real production incident — three hours of runaway retries that cost $32 — that led me to rebuild every Claude agent with a three-layer kill switch: in-process guards, platform-level kill flags on Cloudflare KV, and an observer worker that catches the warning signs within three minutes. Working TypeScript and operational metrics included.

◉ Claude AI/2026-05-18Intermediate

Two Weeks of Reviewing Crashlytics Weekly with Claude in Chrome

I let Claude in Chrome walk through Firebase Crashlytics dashboards once a week instead of checking them every morning. Notes from two weeks of running this loose division of labor as an indie developer behind 50M+ downloads.

⟐ Claude Code/2026-05-18Advanced

Running Apple Privacy Manifest as an Indie Developer — Catching Dependency Drift with Claude Code

Apple Privacy Manifest (PrivacyInfo.xcprivacy) is a quietly painful area for indie iOS developers. Drawing on twelve years of running iOS apps with over 50 million combined downloads, this article walks through how I use Claude Code to detect drift, respond to rejections, and bake the whole flow into CI.

⟐ Claude Code/2026-05-18Intermediate

Why Your `cd` and `export` Vanish Between Claude Code Bash Calls

Claude Code's Bash tool runs each call in a fresh shell, so cd and export never persist. Here's the symptom, the cause, and five practical patterns I use across my Dolice Labs pipelines.