Show HN: Badge that shows how well your codebase fits in an LLM's context window

Maybe it’s useful to dig out the concept of modularization with a distinction between interface and implementation again, and construct agents that are able to make effective use of it.

In the case that interfaces remain unchanged, agents only need to look at the implementation of a single module at a time plus the interfaces it consumes and implements. And when changing interfaces, agents only need to look at the interfaces of the modules concerned, and at most a limited number of implementation considerations.

It’s the very reason why we humans invented modularization: so that we don’t have to hold the complete codebase in our heads (“context windows”) in order to reason about it and make changes to it in a robust and well-grounded way.

Useful and useless (or good and “less good”) aren’t easily mapped to big and small.

From a purely UX perspective, showing a red badge seems you’re conflating “less good” with size. Who is the target for this? Lots of useful codebases are large.

I do agree, however, that there’s value in splitting up domains into something a human can easily learn and keep in their head after, say, a few days of being deeply entrenched. Tokens could actually be a good proxy for this.

For at least some codebases, I'm not sure this is a useful metric. Because you don't usually put the whole codebase in your context at the same time.

For example in my current case, there are lots of files with CSS, SVG icons in separate files, old database migration scripts, etc. Those don't go in the LLM context 99% of the time.

Maybe a more useful metric would be "what percentage of files that have been edited in the last {n} days fit in the context"?

Outside of packages I doubt few of my code bases would fit into this. But the individual domain areas would. I don't care about users in a orders context, I don't care about payments when dealing with imports, no reason an ai should care either. It shouldn't care about implementations if there's an interface referenced, it shouldn't worry about front end when it's dealing with the back etc.

Scoping the Ai to only use the things you'd use seems far wiser than trying to reduce your codebase so it can look at the whole thing when 90% of it is irrelevant.

> Small codebases were always a good thing. With coding agents, there's now a huge advantage to having a codebase small enough that an agent can hold the full thing in context.

It is somewhat ironic that coding agents are notorious for generating much more code than necesary!

I haven't cared too much about repo tokens in a good while.

But my coolest app was a better context creator. I found it hard to extend to actual agentic coding use. Agentic discovery is generally useful and reliable - the overhead of tokens can be managed by the harness (i.e. Claude Code).

https://prompttower.com/

Im curious if there is a deep need for entire codebase to be consumed in the first place?

It would be better to have the architecture support a more decoupled/modular design if you're going to rely heavy on LLMs.

That or let it consume high quality maintained documentation?

On a related note, this type of reasoning is what made me flip my opinion on microservices. I've generally been skeptical of a many-microservice architecture for the last decade but LLMs change that - a small microservice is more likely to fit in a context window.

I think this gestures at a more general point - we're still focusing on how to integrate LLMs into existing dev tooling paradigms. We squeeze LLMs into IDEs for human dev ergonomics but we should start thinking about LLM dev ergonomics - what idioms and design patterns make software development easiest for AIs?

Interesting idea, but I think it might have made more sense to use something like repomix to generate the source bundle and tiktoken’d that. Practically speaking you don’t send many source files in raw text form, either they have some sort of file wrapper with metadata or are pulled in from a tool call where the tool call arguments act as the metadata.

This is an interesting concept. Thank you for sharing. I have an export.sh or export.ps1 script that takes the relevant files in my repository and puts them in a `dump.txt` file inside `docs/llm`.

I am not very good with AI though. Is there a quick and easy way to calculate token count and add this to my dump.txt file, ideally using just simple, included by default Linux tools in bash or simple, included by default Windows tools in powershell?

Thank you in advance.

If you’re worried about fitting the window, make a RAG holding an AST transformation of your codebase

It's a fun, in the "style of the time" thing to track, but within a year or two, context window limitations won't be a thing.

Doubt me?

Think back 2 years. Now compare today. Change is at massive speed, and this issue is top line to be resolved in some fashion.

Some say that the ideal size of an individual function in a codebase is related to the amount of information you can hold in working memory. Maybe the ideal size for a library is the amount you can fit in an LLM context window?

What’s the going rate for tokens in terms of dollars? How much are companies spending on “tokens”?

Also kind of ironic that small codebases are now in vogue, just when google monolithic repos were so popular.

I'm not sure that smaller bases are always better.

Interesting concept, but is it going to age well with context sizes of models are changing all the time (growing, mostly)?

Interesting, but not adding something to my CI for a badge, too paranoid.

Smart idea. Token budgets are becoming the new line count metric for the LLM era.

[dead]

This is a really interesting metric to track. I agree with the sentiment that token budgets are becoming the new 'lines of code' metric. Even though context windows are constantly expanding (like the 200k default you used for Opus), there's still a tangible benefit to keeping a codebase lean. It's not just about fitting it into the window, but also about the signal-to-noise ratio for the agent. The color-coding based on percentage is a nice touch for a quick visual health check.

[flagged]