Weekend project exploring what TypeScript looks like when small, fast LLMs are cheap enough to embed at the type level.

  // Parse natural language
  await SemanticNumber.from("about a dozen") // 12
  await SemanticDate.from("next Monday") // 2025-02-03
  await SemanticBoolean.from("yeah I guess so") // true, confidence: 0.7

  // Classify and validate with plain English
  await message.classify(['question', 'complaint', 'feedback', 'request'])
  await input.validate(["must be valid email", "must not contain profanity"])

  // Context-aware operations
  SemanticNumber.from(150).isReasonable("human age")
  // { reasonable: false, explanation: "Human age rarely exceeds 120" }

  // Same error, different audiences
  error.explain("end-user")   // "We couldn't connect. Check your internet."
  error.explain("developer")  // "ECONNREFUSED on port 5432..."

15+ types: boolean, number, string, array, date, error, URL, promise, map, set, etc.

Alpha—feedback welcome on what feels useful vs gimmicky.

https://github.com/elicollinson/semantic-primitives