# Stargazing

> A GitHub index for agents and people: every repo in the catalog sits in one of 512 clusters, with its nearest neighbours, topics and star count. Static JSON, no key, no account, CORS open (access-control-allow-origin: *).

Base URL: https://app.stargazing.cloud/s
Catalog rebuilt nightly. Files are plain JSON with Content-Type application/json.

## Endpoints

- [meta.json](https://app.stargazing.cloud/s/meta.json): {"version","clusters","shards"}. Today 512 clusters, 4096 repo shards.
- [trending.json](https://app.stargazing.cloud/s/trending.json): {"repos": ["owner/name", ...], "counts": {"owner/name": n}}. Lowercase full names. "repos" is the 100 busiest; "counts" is distinct stargazers over the last 48 hours for every catalog repo with at least 2.
- [c/0.json](https://app.stargazing.cloud/s/c/0.json): cluster by id, 0 to clusters-1. {"id","label","top":[repo names],"people":[[login,score]]}. The label lists the cluster's topics: search by theme here.
- [r/3cb.json](https://app.stargazing.cloud/s/r/3cb.json): repo shard. Object keyed by lowercase "owner/name". Each value: {"n":[[neighbour,similarity]],"c":cluster id,"s":stars,"d":description,"t":[topics]}.

## Find the shard for a repo

Key = first 3 hex digits of FNV-1a (32-bit) over the lowercase "owner/name" UTF-8 bytes.

    function key(name) {
      let h = 2166136261;
      for (const b of new TextEncoder().encode(name.toLowerCase())) {
        h ^= b;
        h = Math.imul(h, 16777619) >>> 0;
      }
      return h.toString(16).padStart(8, "0").slice(0, 3);
    }
    key("honojs/hono"); // "3cb"

## Recipes

- Find codebases by theme: fetch c/0.json to c/511.json, match the label, read "top".
- Find similar repos: fetch r/<key>.json, read "n" of the repo (sorted by similarity, highest first).
- See what is rising: fetch trending.json, then r/<key>.json for details.

## Notes

- Missing files are not 404 on the app host: the single-page app answers with index.html and status 200. Check that the body parses as JSON.
- Only public data. No search endpoint: the index is the files.

## Links

- [Landing page](https://stargazing.cloud)
- [App](https://app.stargazing.cloud)