--- name: fp-errors description: Stop throwing everywhere - handle errors as values using Either and TaskEither for cleaner, more predictable code risk: critical source: community date_added: "2026-09-04" version: 1.0.0 author: kadu tags: - fp-ts - error-handling - either - task-either - typescript - validation - practical --- # Practical Error Handling with fp-ts This skill teaches you how to handle errors without try/catch spaghetti. No academic jargon - just practical patterns for real problems. The core idea: **Errors are just data**. Instead of throwing them into the void and hoping someone catches them, return them as values that TypeScript can track. ## Detailed Guide Read [the detailed guide](references/detailed-guide.md) before executing this skill. It retains the complete procedure and reference material. Treat its safety, prerequisites, and validation requirements as mandatory. For focused work, load the relevant sections; for end-to-end work, read the guide completely. ## When to Use - You need to replace exception-heavy code with `Either` or `TaskEither`. - The task involves validation, domain errors, or clearer error contracts in TypeScript. - You want pragmatic fp-ts error-handling guidance for real application code. --- ## Limitations - Use this skill only when the task clearly matches the scope described above. - Do not treat the output as a substitute for environment-specific validation, testing, or expert review. - Stop and ask for clarification if required inputs, permissions, safety boundaries, or success criteria are missing.