Revision 39Current working draft·All revisions
Specification
The TSON specification, split into two parts, plus the companion documents developed alongside it. Spot an error, or have a comment on the specification? Open an issue on GitHub.
TSON Specification
- TSON Part 1: Text Data Format
The notation and reference encoding of the TSON schema system: the lexer, structural grammar, void sentinel, augmentation syntax (annotations, type annotations, directives), and base type resolution — everything needed to losslessly read and write schemaless TSON data.
- TSON Part 2: Type System and Schema
The centre of the TSON series: the schema grammar, the type system and its operations, the import chain and its resolution model, schema compilation and resolver output, the text encoding rules, and the operation of the import directive.
- TSON Part 3: JSON Encoding
The JSON encoding of the TSON schema system: how schema-governed TSON values are carried in RFC 8259 JSON — the annotation member namespace, the annotation object, atom lexical forms, container syntax, the treatment of void, and the discrimination predicate over the derived disjointness fact.
- TSON Developer Guide
Rationale, extended examples, and implementation guidance for the TSON specification series. Nothing in this guide is normative; where it appears to disagree with [TSON-DATA], [TSON-SCHEMA] or [TSON-JSON], the specifications govern.
Skills
Agent skills that teach an AI assistant to read and write TSON against this revision. Each bundles this revision's own schema sources, so a skill and the spec it describes never drift apart. Unzip a bundle into ~/.claude/skills/for Claude Code, or upload it in claude.ai under Settings › Features.
- tson-data.skill
Write, read, convert, and fix TSON data documents (.tn files) — the Typed Schema Object Notation text format, JSON-like but not a JSON superset, with optional quotes and commas, records vs maps, the void sentinel `_` (there is no `null`), annotations (`@`), type annotations (`!uuid`, `!date`, `!bytes`, `!geo.address`…) and the header directives `!!id` and `!!import`.
- tson-schema.skill
Author, review, and explain TSON schema documents — `.tn` files whose root is tagged `!schema` (after `!!id` and `!!import` header lines), holding `name => type-definition` declarations: records, enums, refined atoms with typed facets like min and max, choices, generic templates, field groups, dependent fields and references, for the TSON (Typed Schema Object Notation) type system at tson.io.
Schema Source Files
The normative TSON schema source files in .tnformat, each followed in parentheses by its non-normative resolved-output fixture where one is published. To check an implementation: parse the source, run the resolver, canonicalise, and compare against the fixture.
Reports
The working documents belonging to this revision: the change log of what was accepted into it, and the non-normative reports written against it, which record findings and design directions under consideration rather than committed specification.
- TSON 2026 Revision 39 — Change Log
Adjudicated 2026-11-08. The six normative artifacts and five resolved fixtures are at `/2026/39/` identities, each pin verified over the shipped bytes, numeric and core re-stamped after the implementation's pass, and listed in Part 2 §13.2 (§6). Part 1, Part 2, Part 3 and the Developer Guide are revised against them in the order §3 lists; Part 3 arrived partly consumed and is completed in a second pass (§7); an independent verification pass over the four documents, the register and the artifacts is recorded in §8, and the implementation's own, which folded sixty findings into the text, in §9.
- SPEC-FEEDBACK.md (24 entries, renumbered against Revision 38; all new — Revision 38 closed every entry open against Revision 37)
- Revised companion artifacts at /2026/39/ identities: meta.tn (the kernel), numeric.tn, temporal.tn, net.tn, core.tn, policy.tn and five resolved fixtures (implementing #3, #4, #5, #6, #7, #8, #9, #10, #11, #12, #13, #14, #15, #16, #17, #18, #19 and #21)
- tson-part3-json.md, edited directly as findings arose (carrying the Part 3 halves of #6, #8, #11, #12, #13, #14 and #21)
Implementations of TSON (parsers, encoders, libraries) may be licensed however you choose; the specification's license applies to the written text, not to code that implements it.