# developer-tools

CLAUDE.md is a suggestion. Hooks are commands. This post covers 8 battle-tested Claude Code Hooks — from auto-formatting and blocking dangerous commands to protecting sensitive files and auto-committing. Copy, paste, done.

Figma's MCP server now lets AI agents like Claude Code and Codex work directly on the design canvas using your team's design system. With skills (markdown instruction files), agents follow your conventions, components, and variables — turning static design guidelines into rules that agents actually obey.

Boris Cherny shares 15 lesser-known Claude Code features he uses every day — from the mobile app and loop/schedule to worktrees and voice input.

Why does Claude perform great in one repo and turn dumb in the next? The answer is the .claude/ folder. Akshay breaks down the full structure: three-level CLAUDE.md, custom commands, agents, permissions, and the global ~/.claude/ you probably didn't know existed.

Thariq from Anthropic shares what they've learned from running hundreds of Claude Code Skills internally: Skills are folders not just markdown files, they cluster into 9 categories, and the secret sauce is in the gotchas section, progressive disclosure, and writing descriptions for the model — not for humans.

Andrew Ng released an open-source tool called Context Hub that gives coding agents access to up-to-date API docs. Agents can also leave notes for their future selves, building knowledge across sessions.

We had Claude Opus run E2E tests on our own blog using Playwright, agent-browser, and Rodney. The surprise? The tool mattered way less than the prompt.

Andrew Ng released an open-source tool called Context Hub that gives coding agents access to the latest API docs, reducing outdated API calls and hallucinated parameters. The long-term vision: agents sharing what they learn with each other.

Hamel Husain released evals-skills, a skill set designed for AI product evaluation. It tackles the blind spots agents face during complex tasks — especially distinguishing between different types of hallucinations — so agents can actually use eval platforms effectively.

Anthropic killed third-party OAuth tokens — the only way to use your Claude subscription programmatically is through the official CLI. This post breaks down everything about claude -p (print mode): 5 input methods, 3 output formats, JSON schema for structured output, tool whitelisting, session management, bidirectional streaming, and three production-ready wrapper examples.

Karpathy argues that CLIs are the most natural interface for AI agents — precisely because they're 'legacy' tech. Text in, text out. He demos Claude building a Polymarket terminal dashboard in 3 minutes via CLI, then drops the mic: every product should ask itself — can agents access and use it? CLI, MCP, markdown docs. It's 2026. Build. For. Agents.

Claude Code's UI change to 'Read 3 files' summaries ignited developer fury on HN: they felt the AI hid its actions. Boris Cherny responded, admitted mistakes, and shipped fixes. This revealed the core tension in AI tool design: simplicity vs. transparency.

Simon Willison doubles down on his stance: CLI tools beat MCP in almost every scenario for coding agents. Lower token cost, zero extra dependencies, and LLMs natively know how to call --help. Anthropic themselves proposed a 'third way' with code-execution-with-MCP, acknowledging MCP's token waste problem. This article breaks down the full MCP vs CLI trade-off, including a real-world case study from the ShroomDog team.

Steve Yegge's 'AI Vampire' theory: AI boosts productivity 10x, but who gets the 9x gain? If the company takes all, burnout. If you take all, company dies. Agentic coding is 3-4 hrs/day max. Yegge's $/hr formula: control the denominator, not the numerator.

GitHub's Agent HQ now offers multi-agent support (Claude, Codex, Copilot) for Copilot Pro+ & Enterprise users. Run multiple AIs simultaneously in GitHub/VS Code to tackle problems from different angles. Outputs become Draft PRs. A paradigm shift for code review.

Claude Code creator Boris Cherny posted a 12-tweet thread breaking down why engineers love Claude Code: extreme customizability — hooks, plugins, LSPs, MCPs, skills, custom agents, output styles, 37 settings, 84 env vars, all committable to git for team sharing.

Hook up Codex as an MCP server inside Claude Code with a single command. Why fight Codex CLI's rough edges when you can plug its brain into a better body?

Matt Pocock (TypeScript guru, Ralph Loops evangelist) released a Claude Code skill: git-guardrails. It uses a PreToolUse hook to intercept dangerous git commands (push, reset --hard, clean -f, etc.), so you can safely let your AI agent run in YOLO mode inside Docker Sandbox without worrying about it blowing up your git history. One command to install, more reliable than any prompt engineering.

Simon Willison's Showboat (AI-generated demo docs) & Rodney (CLI browser automation) tackle AI agent code verification. How to know 'all tests pass' means it works? Agents were caught cheating by directly editing demo files. #AI #OpenSource

Armin Ronacher (creator of Flask, Jinja2, CTO of Sentry) argues current programming languages were designed for 'humans who type slowly.' The AI agent era has different needs. He details what agents love/hate, and why Go accidentally became the winner of the agentic coding era.

Google just launched the Developer Knowledge API and an official MCP Server (Public Preview) that lets AI coding tools query the latest Google docs—Firebase, Android, Google Cloud, Chrome, you name it. No more debugging AI-generated code that uses APIs from three versions ago or functions that literally don't exist.

Berkeley Haas study: AI tools make employees work faster, take on more, and work longer hours, often unasked. Simon Willison finds LLMs draining. How can Tech Leads protect teams when 'just one more prompt' becomes the new overtime?

Anthropic just released Opus 4.6 Fast Mode — same model, 2.5x faster responses. The catch? API pricing jumps from $5/$25 to $30/$150 per MTok — a 6x increase. Boris Cherny calls it a 'huge unlock.' But when should you actually use it? Let's do the math.

Simon Willison shares his 2026 LLM predictions on Oxide and Friends podcast — LLM code quality will be undeniable, sandboxing will finally get solved, and there's a prediction about kākāpō parrots (◕‿◕)

From 80% manual coding to 80% AI agents, Karpathy calls this the biggest change in his 20-year programming career

Simon Willison says the new skill for AI coding isn't writing prompts—it's 'designing agentic loops': carefully picking tools, setting goals, and letting AI brute force its way to solutions through iteration.

When you instinctively think 'neat feature idea, but not worth the time' and then prompt Claude Code anyway — because your 25 years of intuition no longer match reality