Claude-Code on Tokenise

A PreToolUse hook is the guardrail that survives bypass mode

Mon, 05 Oct 2026 22:30:00 +0000

Permission prompts are only as strong as the mode you’re running in. Switch to bypass mode, or launch with --dangerously-skip-permissions, and the prompts are gone. A PreToolUse hook is different: according to the Claude Code hooks guide , it fires before any permission-mode check, and a deny from it blocks the tool even in bypassPermissions mode.

Build a Claude Code subagent that reviews your diff with fresh eyes

Sun, 04 Oct 2026 17:00:00 +0000

An agent that just wrote a change is a poor reviewer of it. It remembers why each decision was made, so it reads its own code charitably. A reviewer that starts with nothing but the diff and a checklist has no such bias. Claude Code subagents are a convenient way to get one.

What 16 parallel agents building a C compiler teach about running agents at scale

Sun, 04 Oct 2026 12:00:00 +0000

Anthropic’s engineering team handed 16 Claude instances a goal, a shared repo and a test suite, and let them write a C compiler in Rust. The result, described in an engineering post , is a roughly 100,000-line compiler that can build Linux 6.9 on x86, ARM and RISC-V, plus projects like SQLite, postgres and redis. It took nearly two weeks, close to 2,000 Claude Code sessions, 2 billion input tokens and 140 million output tokens, for just under $20,000.

Let the agent interview you, then write the spec, then start fresh

Sat, 03 Oct 2026 17:00:00 +0000

Big features fail in a predictable way when you hand them to an agent in one prompt. The agent fills every gap in your description with a guess, builds confidently on the guesses, and you find out about the wrong ones at review. A better move is to make it ask first.

Claude Code's auto mode catches most risky actions. Anthropic's numbers show what it misses

Sat, 03 Oct 2026 07:00:00 +0000

Anthropic published how Claude Code’s auto mode works, with measured error rates. That’s unusual for a security feature, and it makes the engineering post worth reading before you let an agent run unattended. The full write-up is on Anthropic’s engineering blog.

Run parallel Claude Code sessions without them stepping on each other

Fri, 02 Oct 2026 07:00:00 +0000

Two Claude Code sessions in the same checkout will eventually edit the same file. Git worktrees are the standard answer: each session gets its own working directory and branch, backed by the same repository history. Claude Code has a flag for it, and the worktree docs cover more edge cases than the one-liner suggests.

Your CLAUDE.md is probably too long. Here's how to cut it

Thu, 01 Oct 2026 07:00:00 +0000

A CLAUDE.md file starts life as five useful lines. Six months later it’s two hundred, half of which describe things Claude could work out by reading your code, and the instruction you actually care about is somewhere around line 140.

Stop telling your AI agent to 'fix the bug'. Make it reproduce it first

Wed, 30 Sep 2026 12:00:00 +0000

“Fix the login bug” is a terrible prompt for a coding agent, and a frustrating one to debug when it goes wrong. The agent will read some code, find something plausible, change it, and tell you it’s fixed. Sometimes it is. Sometimes it has patched a bug you didn’t have.

Make Claude Code run your tests before it's allowed to say it's done

Wed, 30 Sep 2026 07:00:00 +0000

Telling Claude Code to run the tests in CLAUDE.md is a request. It usually works, and sometimes it doesn’t. If you want it to work every time, Claude Code has a mechanism for that: a Stop hook, a script that runs when Claude thinks it’s finished and can refuse to let it stop.