[bcherny]

Hey, Boris from the CC team here. I agree, we're working on consolidating these. Going forward it will just be the built-in /code-review skill.

Here's how to use the skill on the latest version:

/code-review # do a balanced code review. checks for bugs and inconsistencies, poor code quality, duplication, band aids, etc.

/code-review --fix # same as above, but also fix the issues

# choose an explicit effort level (defaults to your current effort level). all of these also accept --fix:

/code-review low

/code-review medium

/code-review high

/code-review xhigh

/code-review max

# do an expensive and extremely thorough review (reliably catches >99% of bugs, costs $3-20 per review depending on complexity):

/code-review ultra

Open to feedback if anyone has feedback or ideas for how to make these even nicer to use.

[bix6]

Hi Boris, what is the advantage of using /code-review vs just asking Opus to “code review”?

As a casual user working on hobby projects, I struggle to keep up with the pace of changes and knowing what to use when. My default now is to use Opus for all coding (sonnet is fine but seems dumber) and to prompt it for everything I need. I’ve had great success with this but clearly I’m missing power user functions with the slash commands and such.

[extr]

The advantage is that /code-review supplies a structured idea of how to review and what that process should look like and then launches independent subagents to approach the issue from multiple angles.

It's analogous to how in the early days you could see benefits by telling the models to "think step by step". /code-review is something like "review angle by angle". "Consider removed behavior" and also "Look at language gotchas" and also "Look at test changes"...etc. Yes these are all somewhat implicitly already part of what "code review" means, but the models perform best with explicitness.

If you want my 2c as a power user: just don't think about it and use /code-review xhigh --fix. This will cover like 98% of what you want out of code review. It's a good skill.

[HlessClaudesman]

We've all spent time -fixing someone's bright idea of a -fix. I'm sceptical of the time saving of applying a -fix before I understand the problem(s).

Outsourcing comprehension to a machine is probably gonna cost you more time in the long run.

[extr]

I don't even bother looking at the code until I've run a code review pass on it. Why waste my time with trivial bug fixes? I find the best way to spend time right now is like:

- Defining the issue/ticket, what "success" looks like (if I have a good idea of this), high level approach guidance 50%

- Dispatch agent to work on it 5%

- Occasionally return and nudge agent + send /simplify or /code-review 5%

- Look at the code/session summary, divergences from the plan, ask followup questions 40%

Occasionally yes there is some solution the AI chose that is suboptimal and I would prefer fixed in a different way. Mostly though it's straightforward.

[bix6]

Thank you I will try this!

Is there something equivalent when coding in the first place? Eg /code high “prompt”

[extr]

Are you thinking of the /effort level in Claude Code? I would just go with xhigh as a reasonable default. Most important thing in prompting is specifying what "done" and "success" looks like to you. Ask Claude to help you come up with a well formed request and spend most of your time on that, then paste that into a brand new session.

[bix6]

No more like is there a specific slash tool to be using when coding or planning. I guess that’s just Claude code in general but since there’s a specific review tool I was curious about specific coding tools

[sdevonoes]

It’s simpler to just use “review code”. It’s also way cheaper

[pverheggen]

As a general rule, I'd give the Markdown a read for any skills/commands you might find useful, it'll give you a good idea of the specifics it adds.

https://github.com/anthropics/claude-code/blob/main/plugins/...

[bcherny]

/code-review has a specific prompt that we've found is a good balance of precision, recall, and cost. You could totally roll your own prompt also.

[bix6]

And why would someone use the various levels? Is a low code review even worth running? And how do I know what level to use in the first place?

This stuff all seems so nebulous to me and I’ve yet to see anything that says use x in y situation. So I default to higher effort levels than I likely need.

[mil22]

Hey Boris, thanks for the great product and for listening!

I find the mix between slash commands that are programmatic harness configuration and control commands (/config, /model, /feedback, /fork, /usage, etc.) and ones that are little more than prompt template insertion (/code-review, /<skill>, etc.) to be a little confusing and unnecessary. A slash command should be one thing, and one thing only: a command for the harness, not the agent.

When I invoke a slash command like /code-review, I should be invoking some additional harness functionality, something above and beyond the agent's sphere of influence - not just pasting some hidden text into the next turn. Otherwise, why wouldn't I just say "Claude, review this code"?

Yet most of these "added value" commands bloating the slash command list, are just shortcuts for copy and paste. I don't want to go to have to learn the syntax of a special /code-review command (which options are positional args, which are --flags, etc.), and I'm much less likely to use or even be aware of a command like this, when I can just ask "Do a balanced code review and fix the issues", or use the GUI to set the effort level to xhigh before asking "Review my code." That way I can also be more specific about exactly what I need, rather than relying on what's in the canned prompt - a prompt which I'll probably never read and vet myself anyway. The value added by the slash command needs to be really high compared to just typing a prompt, for it to justify the friction of discovery and learning the syntax.

So I suppose I'm advocating for a different system. Keep slash commands for meta-level harness control and configuration, and add a new mechanism for canned prompt insertion, one which is tailor made for that purpose rather than overloading the slash command system. Let the user see what's in the canned prompts, and even make adjustments or edits as needed before sending them, one-time or persisted. Provide a GUI in the app with the user's favorite prompts, where the user can add, delete, and edit them, making it easy to invoke and insert them as needed. Or let the agent automatically discover and use them as needed, rather than requiring the user to remember and recall their magic shortcuts and their arguments. That's just one idea.

Skills, plugins, commands, and so on, need to be consolidated not just for code review of course but across the full architecture of how prompt templates are managed.

[wonkyfruit]

What clicked for me recently was treating skills as composable. Having meta-skills that call smaller skills in order. The "skill vs command vs subagent" confusion partly dissolves once you let skills call other skills. The meta-skill holds the workflow state, the smaller ones each do one job well.

[8note]

> # do an expensive and extremely thorough review (reliably catches >99% of bugs, costs $3-20 per review depending on complexity):

/code-review ultra

main suggestion would be to sound a lot less optimistic about that it finds 99% of bugs or that its at all thorough, and instead list that it is time capped, and will only find bugs that you explicitly tell it to look for.

i used my three runs of ultrareview.

the first run with no other prompting found a couple typos in markdown only

the second one i prompted it with several themes of known open bugs in the code, and it found 6 items

and then the third one i ran after doing an actual long audit through gemini to make a much more detailed prompt about issues in the code

and for that one, instead of doing an exhaustive run, it just never started, so no idea if it worked

but the experience had no relation at all with the reliability or thoroughness claims

[bmitc]

Why doesn't Claude invoke LSPs? It always asks to install them, but then it never uses them, as mentioned in the comment you replied to.

[extr]

Hey Boris, some feedback. I like the new /code-review skill but was disappointed you guys removed /simplify because I quite liked the focus on finding code reuse/efficiency opportunities.

I see now in 2.1.152 you added those focus areas back to /code-review, but still bundled with the correctness finding. It would be great to have more fine grained control over the /code-review angles beyond just effort level. Or maybe you would recommend that I just specify that as freeform input after effort level?

[bcherny]

Yep, you can add free-form input. Will update /simplify to only check for code quality and not bugs (the way it used to work), that's a good suggestion.

[extr]

Damn already there in 154. Thank you man.

[arps18]

Thanks, Boris, for reading and reviewing :)

[svieira]

> reliably catches >99% of bugs

In what scope?