# Oracle

Long-lived multi-browser geometry service. Speaks newline-delimited JSON on
stdio, per `docs/dump-format.md`.

## Run

    node oracle.mjs [--engines=chromium,firefox,webkit]

Launches one persistent browser/context/page per engine (default: all three),
reads one JSON request per line from stdin, writes one JSON response per line
to stdout. Diagnostics go to stderr. Send `{"id":"1","op":"ping"}` or
`{"id":"1","op":"shutdown"}` for control, `{"id":"1","html":"...","engines":[...]}`
for a dump.

## Selftest

    node selftest.mjs [--engines=chromium,firefox,webkit]

Spawns the oracle, drives ping plus a few small HTML cases, prints
PASS/FAIL per check, exits non-zero on failure.