Specification
The normative definition of CFDL: the grammar, the expression environment, the compiler's obligations, the diagnostic register, the pack interface, and the three JSON schemas the toolchain reads and writes.
These pages exist so that a second implementation could be written from them, and so that anything consuming CFDL's output has a contract to hold it to. They describe behavior that most people modeling a deal never need to think about.
If you are building a model, you want Reference instead. It covers the same ground at the altitude of the work — what a thing does, when you would reach for it, and how to get a particular result.
What is here
| Language specification | Types, declarations, evaluation, and the rules a compiler must enforce |
| Grammar | The EBNF |
| Expression environment | Every binding and builtin available to an expression |
| Compiler specification | Determinism, canonical ordering, and stable identity |
| Diagnostics | The complete code register, with severities |
| Pack interface | How a domain pack extends the language |
| IR schema | The compiled intermediate representation |
| Results schema | The results document |
The three JSON schemas are also served directly, for validation in your own tooling: IR · Results · Run configuration, which the run-config reference restates · Grammar.
Stability
The schemas carry their own version field, and a run records the engine version that produced it. Where a specification page and the engine disagree, the engine is the defect — these documents are normative.