Promise boundary

SignatureKit APIs return Effect programs. In React handlers, server actions, route handlers, and job workers, run the program once at the boundary and convert the typed error channel into a Result value.

promise-boundary.ts

import { cmsErrorMessages } from "@signature-kit/cms/config"
import { errorMessage } from "@signature-kit/i18n"
import { pdfErrorMessages } from "@signature-kit/pdf/config"
import { signatureKitErrorMessages } from "@signature-kit/signatures"
import { Effect, Result } from "effect"

const result = await Effect.runPromise(Effect.result(program))

if (Result.isFailure(result)) {
  const message = errorMessage(result.failure, {
    locale: "pt-BR",
    catalogs: [pdfErrorMessages, cmsErrorMessages, signatureKitErrorMessages],
  })

  return { ok: false, message, error: result.failure }
}

return { ok: true, value: result.success }

Use this shape instead of try/catch and string sniffing. The failure remains the real tagged error (PdfError, CmsError, or SignatureKitError), so UI copy can come from @signature-kit/i18n while telemetry still receives the structured code, operation, and schema metadata.

Library internals should keep returning Effect. Effect.runPromise belongs at the app/runtime boundary.