A0 runs on your own machine — the client starts it, so there is no endpoint to ping. Last commit 17 Oct 2026.
Write, check, run and compile A0 programs through revision-checked structured edits.
What the code does
We read the source, 9 h ago · rules ccca72095570
What this server is able to do. For an MCP server this is often the job itself — a terminal server runs commands because that is what it is for. Listed so you know what you are plugging in, not as an accusation.
if (ty === 'u32') return Number((model.eval(v as never, true) as { value(): bigint }).value());
const r = spawnSync(process.execPath, [join(here, `${script}.js`), ...args], {
re: /unexpected 'end' before ret|is not used by any node|duplicate edit|duplicate definition|rec expects|select expects|expects \d+ (extra )?arguments, got|needs \d+ operands|out of range|expected 'fn name types|expected 0 arguments/,
int status = system(cmd);
Is this your server and something here is wrong? Tell us — corrections are free and do not require a plan.
This code can reach further than it looks
We found places where it runs commands, builds paths or queries from values it is given. None of that is a flaw by itself — it becomes one when the code changes, and code changes quietly between releases. We re-read it on every one.
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A0 — questions
Answers built from our own checks of this server.