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Guides

Hands-on guides and migrations for developers who build with AI agents.

Cover: Playwright MCP, tested in Claude Code 2.1.312. One snapshot of Hacker News cost 18,386 tokens. The Claude Code install command with the double dash, 25 tools by default and 71 with every capability, and the warning that Playwright MCP is not a security boundary

Guides

Playwright MCP server: setup in Claude Code, Codex and Cursor

Set up the Playwright MCP server in Claude Code, Codex and Cursor with tested commands, plus its 25 tools, snapshot token costs and safe settings.

CodexGuild ResearchOct 29, 202613 min read

Cover: Pro or Max? 30 days of Claude Code worth $2,090 at API prices on a $200 plan, with the four options (Pro $20, Max 5x $100, Max 20x $200, API per token) and zero usage limits hit in 30 days

Guides

Claude Pro vs Max for Claude Code: what a month really costs

Claude Pro vs Max for Claude Code: prices, how the 5-hour and weekly limits work, and our measured month: $2,090 of usage at API prices on a $200 Max plan.

CodexGuild ResearchOct 29, 20269 min read

Cover: Point or import? A CLAUDE.md that says "See AGENTS.md for the shared agent instructions"; pointers like it got AGENTS.md read and followed in 2 of 12 runs, an @AGENTS.md import in 3 of 3

Guides

CLAUDE.md and AGENTS.md: best practices from 1,000 repos

What to put in a CLAUDE.md or AGENTS.md and how to keep both. We linted 1,000 top repos and tested Claude Code: "See AGENTS.md" worked 2 times in 12.

CodexGuild ResearchOct 29, 202614 min read

Cover: Hooks that really block. A hook script that prints Blocked and exits 1, and the result: the command ran anyway, 3 of 3 times

Guides

Claude Code hooks: a working guide with tested examples

What Claude Code hooks are, where they go and how they answer — plus five hooks to copy. Exit 1 doesn't block; a timed-out hook lets the command run.

CodexGuild ResearchOct 27, 202613 min read

Cover: Your agent's keys, next to an agent debugging a login that runs cd ~/.codex and sed on auth.json, and a credential check stopping it before the file is read

Guides

Where Claude Code, Codex and Cursor keep your API keys

After the OpenCode breach: where each coding agent stores logins, provider keys and MCP tokens, what we found on a real machine, and how to lock them down.

CodexGuild ResearchOct 23, 20269 min read

Cover: Guardrails stay on, next to an agent adding continue-on-error true to the Tests step of a CI workflow and a guardrail check stopping the edit before it ran

Guides

Stop your coding agent from switching off its own guardrails

OpenAI's agents weakened their own monitoring. We tested what stops Claude Code and Cursor from removing hooks, CI checks and git hooks, and fixed what didn't.

CodexGuild ResearchOct 23, 202610 min read

Cover: Stop fake packages, next to an agent running pip install reqeusts and a pre-install check answering that reqeusts does not exist on PyPI and blocking it before it ran

Guides

Stop your coding agent from installing fake packages

A tested setup for Claude Code, Cursor and Codex: a pre-install hook that blocks hallucinated and malicious packages, package-manager age gates and agent rules.

CodexGuild ResearchOct 22, 20268 min read

Cover: Read it before it runs, next to a SKILL.md that pre-approves Bash, pipes an install script to bash and ships a script that opens AWS credentials and calls a telemetry URL, flagged critical and high

Guides

How to check a Skill or MCP server before you install it

A 10-minute review for Agent Skills and MCP servers: who published it, what runs, what it can reach, how to pin it. With scan data from 55,000 listings.

CodexGuild ResearchOct 22, 20269 min read