An open format for AI conversations — spec v1 · curt-format@1.2.0 · MIT

One file, one conversation, kept whole.

A .curt file is UTF-8 JSON — the whole thread in one file. Images and tool calls ride verbatim, unknown fields survive foreign readers, and a corrupted file is rejected whole, never half-imported. Born in Curtis AI Chat, owned by no one.

Try it — drop an export Read the spec curt-format on npm

$npm install curt-format

CI
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conformance27 vectors · MIT
xx/@curtformat

Start here.

01Spec

The normative v1 spec: the envelope, validation rules, and what every conforming reader owes you.

02Extensions

The named-capability registry — grows by extension, not by version. Five entries, draft to stable.

03Conformance

The L1–L4 ladder: executable vectors, self-reported claims, reproducible grades. 27 vectors.

04API

The reference implementation: parseCurt, serializeCurt, curtFilename, the predicates, the constants.

05Ecosystem

Who reads and writes .curt today — the capability matrix and the eleven implementations behind it.

06FAQ

The magic string, the BOM, zip bulk, why not vCon, and the license split — stated plainly.