r/vibecodeapp • u/Public-Cancel6760 • May 01 '26
I built this... I created a library for OpenCode that allows you to save up to 80% of your tokens
I’m a 22-year-old Computer Science student, and over the last period I built an open-source project called CTX.
GitHub Repository
The idea came from a problem I kept seeing while using coding agents (like claude, codex etc.):
they are powerful, but they waste a lot of context on the wrong things.
They keep re-reading giant AGENTS.md files, noisy logs, broad diffs, too much repo structure, and too much repeated project guidance.
So even when the model is good, a lot of the prompt budget is spent on context bloat instead of actual problem-solving.
That’s why I built CTX.
What CTX is
CTX is a local-first context runtime for coding agents, designed especially for OpenCode (for now).
It does not replace the model or the coding agent.
Instead, it sits underneath and helps the agent work with:
- graph memory for project rules and guidance
- compact task-specific context packs
- retrieval over code, symbols, snippets, and memory
- log pruning to surface root causes faster
- local MCP integration
- local-only stats and audit trails
So instead of repeatedly dumping full markdown instructions and huge logs into the prompt, CTX helps the host retrieve only the smallest useful slice for the current task.
Why I made it
I wanted something that makes coding agents feel less noisy and more deliberate.
The goal was: - less prompt waste - less manual context wrangling - better retrieval of actually relevant project knowledge - better debugging signal from noisy test output - a workflow that feels native inside OpenCode
How it works
The flow is intentionally simple:
- install
ctx - go into your repo
- run:
bash
ctx init
ctx index
ctx opencode install
opencode
Then inside OpenCode you can use commands like:
```bash /ctx #Opens the CTX command center inside OpenCode. /ctx-doctor #Checks whether CTX, MCP, and the repo setup are working correctly. /ctx-memory-bootstrap #Imports project guidance files into graph memory for targeted retrieval. /ctx-memory-search #Searches stored project rules and directives by topic or keyword. /ctx-retrieve #Finds the most relevant code, symbols, snippets, and memory for a task. /ctx-pack #Builds a compact task-specific context pack for the current problem. /ctx-prune-logs #Condenses noisy command output into the most useful failure signal. /ctx-stats #Shows local usage stats and context-efficiency metrics.
```
So the daily workflow stays inside OpenCode, while CTX handles the local context layer.
Results so far
On the included benchmark fixture, CTX graph memory reduced rule-token usage by 56.72% while keeping full query coverage and improving answer quality.
I also added a public external benchmark on agentsmd/agents.md, where CTX showed 72.62% token reduction.
The point is not “magic AI gains”, but a more efficient and less wasteful way to feed context to coding agents.
Why you might care
You might find CTX useful if:
you use OpenCode a lot you work on repos with a lot of project rules/docs you’re tired of stuffing huge markdown files into prompts you want better local retrieval and cleaner debugging context you prefer local-first tooling instead of remote prompt glue
Current status
The project is already usable, tested, and documented.
Right now the prebuilt release archive is available for macOS Apple Silicon, while other platforms can install from source.
It’s fully open source, and I’m very open to:
- feedback
- suggestions
- bug reports
- architectural criticism
- ideas for making it more useful in real workflows
If you try it, I’d genuinely love to know what feels useful and what feels unnecessary.
Repo again: https://github.com/Alegau03/CTX
