TS4023 with Effect Error Types

Problem

Exporting function returning Effect → TypeScript generates .d.ts → error types in Effect's error channel not exported from source package → TS4023.

TS4023 message is misleading: mentions internal Effect types (Channel, Sink, Stream from effect/Cause), not actual missing errors.

Solution

Export ALL error types that appear in any Effect's error channel - including non-exported class definitions.

1. Find ALL TaggedError classes (not just exported ones)

# Find Data.TaggedError and Schema.TaggedError (both can appear in Effect error channels)
rg "class \w+Error extends (Data|Schema)\.TaggedError" packages/<package-name>/src