TypeScript's insistence on being a static checking/compile time only system is such a sad wound to the whole ecosystem. I don't want TypeScript to be a runtime checker, but I want it to export useful usable type data for classes, functions, objects. TypeScript feels like the best source of truth we have, but instead so many of the attempts to reflect on what we have are all going it alone, having to define their own model and their own builders for describing what stuff is. You've mentioned 5 major areas where reflection is a core part of the mission, and each of these have multiple implementations.

There is the old TypeScript type emitter, reflect-metadata, which would provide some type information at runtime, but it targets very old decorator and metadata specifications, not the current version. I don't super know how accurate or complete it's model really is, how closely it writes down what typescript knows versus how much it defines its own model to export to. https://www.npmjs.com/package/reflect-metadata

We are maybe at the cusp of some unifying, some coming together, albeit not via typescript at this time, still as a separate layer. The Standard Schema project has support from I dare say most of the top validation libraries. But extending this to API definitions, ORM tools is in extremely early stages. https://github.com/standard-schema/standard-schema?tab=readm...