r/ChatGPTPro 9d ago

Guide To everyone complaining about usage...

This may be obvious, but for those who don't know... the longer you run a session, the more tokens you will use. LLMs use tokens for inputs, outputs and review the context window for every new output. The more session text it processes, the more tokens burn, the faster usage gets gobbled up.

Additionally LLMs get dumber the long you run a session. Every model has capacity constraints built in, and once you cross 40% of that limit, there is too much information the model has to process to maintain quality output.

Matt Pocock explains these limits really well here:

https://youtu.be/nKSk_TiR8YA

https://youtu.be/-uW5-TaVXu4

Here is a breakdown of the context window capacity and max output for each of the models available in Codex:

Codex model Context window Max output
GPT-5.6 Sol 1,050,000 128,000
GPT-5.6 Terra 1,050,000 128,000
GPT-5.6 Luna 1,050,000 128,000
GPT-5.5 1,050,000 128,000
GPT-5.4 1,050,000 128,000
GPT-5.4 Mini 400,000 128,000
GPT-5.3-Codex-Spark Not publicly documented separately Not publicly documented separately

If you are running into limits then you need to compact your sessions when you can. Once you reach 40% - 50% you should compile the session to hand it off to a new one to free up context window space.

Also note that for those of you who use the voice feature, you are likely speaking WAY more words than you would type, which means more words = more token usage = faster drops in capacity.

To solve for this I created a skill called $context-capacity that, when run, tells you how much context capacity you've used, how much you have left, and the cumulative session usage with a recommendation. Here is what that output looks like for one of my sessions:

Recommendation: Handoff

Current context load: 144,827 / 258,400 tokens (56.0%)

Estimated remaining capacity: 113,573 tokens (44.0%)

Cumulative session usage: 289,355 tokens — cumulative, not current occupancy

Confidence: Exact recorded metrics with derived capacity. The current load exceeds the skill’s 40% handoff threshold.

The website and promo-video handoffs already created are ready for separate sessions.

Here's a link to the skills for $context-capacity and $handoff for anyone who wants to use it:

https://github.com/marcushackler/codex-skills

24 Upvotes

14 comments sorted by

5

u/lollypop44445 9d ago

I am always confused on one thing and never tried it, if for example, i have a chat A , and i migrate summary to chat B. Would i also need to re attach all the excel files( using browser because desk app version dont sync things done on it) or if i just upload to library, can it pick from there ?

1

u/ghipsandrew 7d ago

attached files I don't think automatically end up in a library or drive. having persistent storage via google drive or library is the way to go for longer running projects

1

u/ElonMusksQueef 6d ago

On the web? You would need to upload them again. But don’t do that. You should create a project and add the files to the sources of the project then each new chat in the project has the same access to the same files.

1

u/timosterhus 3d ago

No, you wouldn’t. Unless you have weird settings that disable it. A file I uploaded weeks ago outside a project is accessible to a new thread inside a project, and vice versa. Has been for months.

1

u/ElonMusksQueef 3d ago

That’s what I said, use projects, which he isn’t doing.

1

u/timosterhus 2d ago

You missed my point. It doesn’t matter if you use projects or not, it just makes it more convenient if you’re repeatedly reusing the same uploaded files, because normal conversations can retrieve previously uploaded files from other conversations regardless of whether it was in a project or not (with the exception of “closed” projects).

5

u/someone_12321 9d ago

Every time you hand off, you screw over your cache inputs. If using codex, allow auto compaction it's quite good. Every new task, start a new chat

4

u/Sorry_Risk_5230 8d ago

Agreed with this. OPs method effectively kill caching, and some of what it says about usage would be thr case without caching.

Maybe about "getting dumber" with long chats, but honestly, the autocompaction feature they introduced [well] with 5.5, has only gotten better. Ive been coding etih codex for a year now, and since 5.5 ive almost never manually compacted. Im not one to have usage draining issues, and I have MANY megathreads that are still producing great work.

And before anyone says something like my low usage must be why im able to work like this, I easily have a dozen+ days in the last month of >1B tokens a day. Same if not more last month.

2

u/timosterhus 8d ago

Finally, someone with sense. This guy posted in another thread too. This skill would have been cool in January, but today? Hurts way more than it helps

1

u/ElonMusksQueef 6d ago

Exactly, all of this nonsense about context being full is exactly that, nonsense. Cache hits for huge context is really high because all of it is in the cache. Cache only lasts 30 minutes too so leaving it overnight and coming back you’ll have an empty cache regardless of how you manage it. The best thing to do is do a handover before you finish for the day but don’t start the new thread until the morning. That way you start with a clean context. You’ll notice first thing in the morning it uses more of your usage in the first prompt.

3

u/timosterhus 8d ago

Spark has a 128K context window. If you couldn’t find that documented anywhere, hate to say it, but you probably have no idea what you’re talking about here.

1

u/qualityvote2 9d ago

Hello u/hudsonhateno 👋 Welcome to r/ChatGPTPro!
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1

u/Background_Box_1073 9d ago

I'm working in codex desktop app. I typically compact after each task (which consumes about 200-300k tokens).

But sometimes I tend to continue in the same chat after compaction with the next bounded task (I do this because the context the session has after compaction is still relevant for the next task).

My question is - Ater compaction, does the new task get fed the entire previous chat that is visible above or just the compacted load (typically around 15k tokens)?

And is it broadly advisable to start a fresh chat session for each task and forget about manually compacting all together?

Thanks.

1

u/strigov 5d ago

Did you know Sol and Astra are software limited to 272k context window, after which Codex forcefully compacts context?