Sign with a typed slot

Sign with a typed slot

Use the tasra-sdk/app interface for new applications. The installed docs/application-api.md describes configuration and authorizers; complete sources are under examples/. Do not lead an operation-bound application through bearer-JWT session signing. Existing JWT/ethers and custody APIs are advanced compatibility paths.

Ethereum wallet and durable transfers

import type {TasraClient, OperationAuthorizer, ApplicationStore} from 'tasra-sdk/app'

export async function sendPayment(tasra: TasraClient, slotId: `0x${string}`,
  to: `0x${string}`, authorize: OperationAuthorizer, store: ApplicationStore) {
  const wallet = await tasra.wallets.fromSlot(slotId, {authorize})
  return wallet.transfer('invoice-42', {to, value: 1n}, store)
}

The wallet adapter handles transaction preparation, exact-operation authorization, verified signing, durable storage and submission. Reusing the same operation name and request reconciles recorded state; do not change the request or generate a new name to bypass an uncertain outcome. Fund the slot account’s gas before sending. Read its public address with (await tasra.slots.ecdsa(slotId)).getAddress().

For applications already using viem, toViemAccount remains an explicit adapter choice and supports message, typed-data and transaction signing. That advanced path leaves broadcast and transaction persistence with the application.

examples/shared-account.ts creates one slot where Alice OR Bob may sign a zero-value self-transfer, confirms both transactions and sends Mallory’s deliberately nonmatching presentation to the real verifier. A user quorum is not enforced by a DCQL values: [alice, bob] list.

Document signatures

import type {TasraClient, OperationAuthorizer} from 'tasra-sdk/app'

export async function signDocumentStatement(
  tasra: TasraClient, slotId: `0x${string}`, statement: Uint8Array, authorize: OperationAuthorizer,
) {
  const slot = await tasra.slots.frost(slotId)
  return slot.sign(statement, {authorize, requireReceipt: true})
}

The document example freezes the PDF digest, request ID, version, chain and assigned signer slots into one statement. Alice and Bob use separate FROST slots and holder-bound authorizations. Completion requires both independently verified signatures over the same statement. Verify against expected signer assignments and anchored keys, not arbitrary keys supplied by a downloaded bundle.

examples/document-signing/ and docs/document-signing.md provide the web app: PDF upload/preview, separate browser wallets, persistent requests, and verified downloads. Preserve the frozen request and attempt ID before submission; duplicate completion returns the saved proof. Interrupted submissions require reconciliation, not automatic re-signing. Keep sender capability and wallet files private. examples/document-signing.ts is the smaller terminal recipe. Neither example provides trusted timestamps or archival verification across key rotations. For one FROST signature requiring a native approver quorum, use tasra-committee-path and examples/credential-approvals.ts instead.

Encryption and advanced APIs

For new encrypted-data applications use slots.bls and tasra-ibe-identity-scoped; public encryption and authorized decryption have separate inputs. IBE returns an identity capability, never a master key.

For an existing integration needing ethers, legacy sessions, shard-delivery or custody primitives, read advanced signing and decryption. Check that exact route is supported by its deployment. A refusal never authorizes switching to a weaker authorization route. Native multi-approver IBE is unsupported.