Ask HN: Which one do you use for planning and coding between sonnet and Opus?

#1

Post by neverenderr » Thu, Jul 30, 2026, 9:21 AM UTC

I use Claude Opus for planning at high effort and Claude Sonnet 5 for coding at max effort.

Re: Ask HN: Which one do you use for planning and coding between sonnet and Opus?

#2

Post by igor_nast » Thu, Jul 30, 2026, 12:10 PM UTC

Opus - planning/review + gpt spark med - implementation. Works better at lower cost.

Re: Ask HN: Which one do you use for planning and coding between sonnet and Opus?

#3

Post by neverenderr » Thu, Jul 30, 2026, 1:39 PM UTC

igor_nast wrote: post #2

Opus - planning/review + gpt spark med - implementation. Works better at lower cost.

I don't have a subscription to Codex, but it's good to know.

Re: Ask HN: Which one do you use for planning and coding between sonnet and Opus?

#4

Post by leros » Thu, Jul 30, 2026, 2:52 PM UTC

I've been using Fable for planning and Opus for coding

Re: Ask HN: Which one do you use for planning and coding between sonnet and Opus?

#5

Post by neverenderr » Thu, Jul 30, 2026, 3:01 PM UTC

leros wrote: post #4

I've been using Fable for planning and Opus for coding

What plan are you on? Max?

Re: Ask HN: Which one do you use for planning and coding between sonnet and Opus?

#6

Post by runjake » Thu, Jul 30, 2026, 3:24 PM UTC

Sonnet 5 Medium and GPT 5.5 Medium for coding.

I drop down to a Mini model for file-based tasks.

Codex keeps trying to revert me back to 5.6 but 5.6 seems to use too many tokens to do the same or slightly inferior job.

I am only on multiple $20 plans.

Re: Ask HN: Which one do you use for planning and coding between sonnet and Opus?

#7

Post by neverenderr » Thu, Jul 30, 2026, 3:47 PM UTC

runjake wrote: post #6

Sonnet 5 Medium and GPT 5.5 Medium for coding. I drop down to a Mini model for file-based tasks. Codex keeps trying to revert me back to 5.6 but 5.6 seems to use too many tokens to do the same or slightly inferior job. I am only on multiple $20 plans.

I see. I am just using the $20 claude paln, so I can't use GPT.

Re: Ask HN: Which one do you use for planning and coding between sonnet and Opus?

#8

Post by leros » Thu, Jul 30, 2026, 5:47 PM UTC

neverenderr wrote: post #5

leros wrote: post #4

I've been using Fable for planning and Opus for coding

What plan are you on? Max?

Max 5X. I have plenty of headroom coding using Opus all day so I figured I may as well use Fable a bit. I have found Fable to do a much better job of understanding a codebase and avoiding subtle bugs.

Re: Ask HN: Which one do you use for planning and coding between sonnet and Opus?

#9

Post by neverenderr » Thu, Jul 30, 2026, 6:33 PM UTC

leros wrote: post #8

neverenderr wrote: post #5

Earlier quoted context omitted.

What plan are you on? Max?

Max 5X. I have plenty of headroom coding using Opus all day so I figured I may as well use Fable a bit. I have found Fable to do a much better job of understanding a codebase and avoiding subtle bugs.

Oh man, I haven't used fable that much, so I can't say much, but based on your experience, I think it seems pretty good. Also, I am on the pro plan, so I can't afford to use fable xD.

Re: Ask HN: Which one do you use for planning and coding between sonnet and Opus?

#10

Post by leros » Thu, Jul 30, 2026, 6:49 PM UTC

neverenderr wrote: post #9

leros wrote: post #8

Earlier quoted context omitted.

Max 5X. I have plenty of headroom coding using Opus all day so I figured I may as well use Fable a bit. I have found Fable to do a much better job of understanding a codebase and avoiding subtle bugs.

Oh man, I haven't used fable that much, so I can't say much, but based on your experience, I think it seems pretty good. Also, I am on the pro plan, so I can't afford to use fable xD.

Opus has been great for me on building simple features or adding new things. Fable has been significantly better for things like "there are subtle bugs in this complex interface I can't figure out, find them". Opus gets a rough idea for some. Fable actually finds all the tiny subtle issues.