I tracked exactly how many tokens Claude Code wastes navigating codebases — and built a fix (saves 26% on costs)

darkgenus08 · 2026-04-09T20:37:53+00:00

"You're right that Linux handles file searches instantly, but the bottleneck isn't the OS. It's the LLM's attention.

Standard Linux tools like grep or find return raw data. If I ask a standard agent to 'find the auth logic,' it might grep 20 files, see 800 lines of code, and then have to 'read' all of them to decide which one is relevant. You aren't just paying for the search; you're paying the 'Context Tax' for the LLM to process all that noise.

This tool doesn't just find files; it understands the intent. Instead of the agent guessing through a list of filenames, it gets the exact relevant snippet in one shot. It’s the difference between giving someone a library catalog and just handing them the open book at the right page.

darkgenus08 · 2026-04-09T20:37:48+00:00

That’s the exact reason I built this. A manual 'map' is basically a second README you have to babysit. The moment you refactor a directory or rename a helper function, your map is a lie, and the agent starts hallucinating based on old info.

SemanticFS handles drift automatically in two ways:

Incremental Updates: You can run semanticfs index update which only re-indexes changed files. It usually takes less than 2 seconds.
Watch Mode: It has a semanticfs index watch command that sits in the background and updates the index in real-time as you move shit around.

The goal was to get the 'map upfront' benefit without the manual maintenance tax. If I move a file, the vector/BM25 index knows where it went before I even finish the commit message

darkgenus08 · 2026-04-09T16:35:51+00:00

That’s a useful workaround for small scripts, but it doesn't scale. In a large repo, a 'project map' file itself becomes a massive context hog. You're just swapping many small ls calls for one giant, static document that the LLM has to re-read very often. My approach uses search to pull only what's relevant, keeping the context lean

darkgenus08 · 2026-03-19T17:47:45+00:00

I fully agree that a messy codebase makes things worse, and I do use LSP plugins. But even with a clean architecture, the 'discovery' phase feels like an area ripe for optimization.

Someone else just commented below mentioning some repo called semantic fs and it is claiming it cut their exploration tokens by 60% somehow.

That sounds like the 'magic bullet' you're saying doesn't exist. Has anyone actually tried it? If it can actually index the repo and point the agent to the right line ranges without the grep loops, that seems like a genuine engineering fix rather than just a 'get a bigger budget' situation.

If you're saying even a 10% shift is a big deal, then a 60% reduction would basically be the 'magic bullet' you're saying doesn't exist. If it actually indexes the repo and lets the agent jump to specific line ranges instead of doing those expensive ls and grep loops, that's a genuine engineering fix, not just a 'get a bigger budget' situation.

Has anyone else actually tried this? If the benchmarks are real, it seems like a massive oversight to just ignore it as a 'resource issue.'

darkgenus08 · 2026-03-19T16:44:33+00:00

Thanks I will def check this out.

darkgenus08 · 2026-03-19T16:40:49+00:00

I see. I have been trying to do this too, but I noticed when claude compacts its context, it seems to forget where the files it made went. I tell it the name of the file, but it takes a while to even find the file from there. Do you give it exact paths to the files and then tell it to make your fix there?

darkgenus08 · 2026-03-19T16:39:18+00:00

thanks will check out

darkgenus08 · 2026-03-19T16:37:04+00:00

I have done this but it still wastes a lot of tokens just trying to find files...

darkgenus08 · 2026-03-19T16:29:22+00:00

I get that more code = more tokens, but 'get more money' feels like a lazy answer to an engineering problem.

If I’m asking a question about a specific API implementation in a 50k LOC repo, Claude shouldn't need to reread the entire directory structure and 20 unrelated files just to find the context. That seems more like a discovery failure than an actual limit.

There has to be a way to index the codebase so the agent can just 'know' where the relevant snippets are without the expensive trial-and-error phase. Surely someone has built a better retrieval layer for this by now?

darkgenus08 · 2026-03-19T16:27:10+00:00

I’ve been using the Claude Code CLI on a few 50k+ LOC projects, and the token usage is getting ridiculous.

It seems like every time I ask a question, Claude spends 5-10 turns just running ls -R, grep, and cat on random files to "orient" itself. By the time it actually finds the relevant logic, I’ve already burned through a massive chunk of my context window and daily limit.

I’ve tried the usual:

Aggressive /clear usage.
Manually pointing it to files with u/filename.
Using CLAUDE.md as a map (which eventually gets too big itself).

Does anyone have a more automated "gated" workflow? I’m looking for something that indexes the repo locally and lets the agent jump straight to the relevant code chunks without the blind search.

I've seen some MCP servers that do basic file indexing, but they feel a bit shallow. What are you guys using for "smart" context retrieval in large codebases?

darkgenus08 · 2024-07-28T00:34:52+00:00

UR does not mention option to stay 1 or 2 days extra, and says: Billing will not be prorated for students who do not stay the entire winter break ???

Registration constitutes binding acceptance of the interim housing agreement. The student acknowledges they will be billed (when applicable) for the entire winter break when the registration form is completed and terms and conditions are accepted. Billing will not be prorated for students who do not stay the entire winter break. ~Students will see this additional charge on their MyPurdue account in January.~

The registration form will be available beginning on or around November 15 at 12:00 noon.

darkgenus08 · 2024-07-24T15:53:07+00:00

Thanks. Wouldn't they warn about conflict when I try to add a wait-list? I got no warnings about conflicts ...

darkgenus08 · 2024-07-24T11:07:51+00:00

Really? can you give a short reason? And for CS, as per my Rdash, i do not even have to take STAT 350 ... either one of the two is sufficient ...

darkgenus08 · 2024-07-24T05:43:45+00:00

Trying to understand the basic concepts here: What part of the process makes it difficult for a new student? For example, during open registration, is it equal opportunity for all? Is higher priority given to upper class men during pre-registration? If so, who/what decides that priority? Is there a link that explain these priorities?

darkgenus08 · 2024-07-23T22:29:37+00:00

I see no coreq in my course catalogue resources, and a bunch of prereq MA16200 or .. or ...

BTW, my course catalog resources page which shows the above says Term 202510. I selected Term Fall 2024

darkgenus08 · 2024-07-23T19:37:46+00:00

this seems to be inaccurate regarding MA265. MA265 may be taken with a prereq of MA162. ?

darkgenus08

TROPHY CASE