What is Prism
A local tool that answers repository questions no single file can.
Prism reads your repository and answers questions that no single file can answer.
The problem
You join a project, or come back after six months. Your editor shows what any one file says. Nothing tells you which files matter, what a change breaks, which parts belong together as a feature, where tests are thin and churn is high, or what the project is actually built with.
What it does
Prism parses source into a local index and derives views from that one store:
| View | Question |
|---|---|
| Repository map | What is in here, and how is it shaped? |
| Dependency / knowledge / feature graphs | What imports what, what symbols mean, which files implement one capability? |
| Repository DNA | What is this built from, and which domains does it span? |
| Health score | Where is risk concentrated, and why? |
| Blast radius | If I change this file, what else is affected? |
Where you use it
| Surface | For |
|---|---|
| VS Code / Cursor | Day-to-day visual reading |
| CLI | Scripts, CI, terminal workflows |
| MCP server | Giving an AI agent real structural knowledge |
| Playground | Trying Prism in a browser without an extension |
Is it for you?
Probably yes if you work in a TypeScript or JavaScript codebase too large to hold in your head.
Probably not if the project is small enough to read in an afternoon, or is written in a language Prism does not parse deeply. See known limitations.
Definitely not if you want something to write code for you. Prism has no model behind it.
Cost
Disk: an index in .prism/ (tens of megabytes on a large monorepo). Time:
seconds for the first index of a few thousand files, then incremental. Privacy:
nothing by default — see consent and privacy.