# @integraledger/lcp > The exports of @integraledger/lcp. Source: https://lcp.integraledger.com/reference/api ## Interfaces ### CarrierAfterH The optional member of a pairing whose carrier the seller writes after H: `advertise`'s checks and placement, without the checks on that carrier. #### Methods ##### advertiseBeforeCarrier()? > `optional` **advertiseBeforeCarrier**(`doc`, `h`, `link`, `offer`, `agreementUrl?`): `unknown` ###### Parameters | Parameter | Type | | --------------- | ------------------- | | `doc` | `never` | | `h` | `` `0x${string}` `` | | `link` | `string` | | `offer` | `never` | | `agreementUrl?` | `string` | ###### Returns `unknown` *** ### PresentedOn What the buyer presents as payment, per surface: the union of the payment types of every pairing on it. Every pairing's `bound` and `reference` take `unknown` and check what they are given. #### Properties | Property | Type | Description | | -------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------- | | `ack` | [`Json`](#json) | ACK defines no payer signature; its `bound` refuses whatever is presented. | | `acp` | [`Presented`](https://lcp.integraledger.com/reference/api/acp#presented) | - | | `ap2` | [`Presented`](https://lcp.integraledger.com/reference/api/ap2#presented) | - | | `card` | [`TapPresented`](https://lcp.integraledger.com/reference/api/card#tappresented) \| [`ViImmediate`](https://lcp.integraledger.com/reference/api/card#viimmediate) \| [`ViAutonomous`](https://lcp.integraledger.com/reference/api/card#viautonomous) | - | | `mpp` | [`MppCredential`](https://lcp.integraledger.com/reference/api/mpp#mppcredential) | - | | `ucp` | [`Presented`](https://lcp.integraledger.com/reference/api/ap2#presented) | - | | `x402` | [`PaymentPayload`](https://lcp.integraledger.com/reference/api/x402#paymentpayload) \| [`HederaPaymentPayload`](https://lcp.integraledger.com/reference/api/hedera#hederapaymentpayload) \| [`ExecutorPaymentPayload`](https://lcp.integraledger.com/reference/api/hedera#executorpaymentpayload) \| [`LnPaymentPayload`](https://lcp.integraledger.com/reference/api/lightning#lnpaymentpayload) \| [`AptosPaymentPayload`](https://lcp.integraledger.com/reference/api/aptos#aptospaymentpayload) \| [`AvmPaymentPayload`](https://lcp.integraledger.com/reference/api/avm#avmpaymentpayload) \| [`CardanoPaymentPayload`](https://lcp.integraledger.com/reference/api/cardano#cardanopaymentpayload) \| [`CasperPaymentPayload`](https://lcp.integraledger.com/reference/api/casper#casperpaymentpayload) \| [`CcdPaymentPayload`](https://lcp.integraledger.com/reference/api/ccd#ccdpaymentpayload) \| [`NearPayment`](https://lcp.integraledger.com/reference/api/near#nearpayment) \| [`PolkadotPaymentPayload`](https://lcp.integraledger.com/reference/api/polkadot#polkadotpaymentpayload) \| [`StarknetPayment`](https://lcp.integraledger.com/reference/api/starknet#starknetpayment) \| [`SuiPaymentPayload`](https://lcp.integraledger.com/reference/api/sui#suipaymentpayload) \| [`TronPayment`](https://lcp.integraledger.com/reference/api/tron#tronpayment) \| [`TvmPayment`](https://lcp.integraledger.com/reference/api/tvm#tvmpayment) \| [`BatchPaymentPayload`](https://lcp.integraledger.com/reference/api/x402-batch-settlement#batchpaymentpayload) \| [`CloudflarePaymentPayload`](https://lcp.integraledger.com/reference/api/x402-batch-settlement#cloudflarepaymentpayload) \| [`SvmPaymentPayload`](https://lcp.integraledger.com/reference/api/x402-exact-solana#svmpaymentpayload) \| [`StellarPaymentPayload`](https://lcp.integraledger.com/reference/api/x402-exact-stellar#stellarpaymentpayload) \| [`XrplPaymentPayload`](https://lcp.integraledger.com/reference/api/x402-exact-xrpl#xrplpaymentpayload) \| [`UptoSvmPaymentPayload`](https://lcp.integraledger.com/reference/api/x402-upto-solana#uptosvmpaymentpayload) | - | *** ### PushMode The optional member of a push-mode pairing: the transaction its credential names, or undefined. #### Methods ##### landedTx()? > `optional` **landedTx**(`presented`): `string` | `undefined` ###### Parameters | Parameter | Type | | ----------- | --------- | | `presented` | `unknown` | ###### Returns `string` | `undefined` *** ### TieRequestOn The request a surface's `tie` takes with its options: x402's request commitment; the others' `tie` takes none. #### Properties | Property | Type | | -------- | ------------------------------------------------------------ | | `ack` | `never` | | `acp` | `never` | | `ap2` | `never` | | `card` | `never` | | `mpp` | `never` | | `ucp` | `never` | | `x402` | [`RequestCommitment`](https://lcp.integraledger.com/reference/api/x402#requestcommitment) | *** ### TxSpelling The optional member of a pairing whose rail spells one transaction id more than one way: the id in the one spelling a record keeps. #### Methods ##### txId()? > `optional` **txId**(`tx`): `string` ###### Parameters | Parameter | Type | | --------- | -------- | | `tx` | `string` | ###### Returns `string` ## Type Aliases ### AtrHash > **AtrHash** = `` `0x${string}` `` `0x` followed by 64 hex digits. Every hash this module emits is lowercase. *** ### Binding > **Binding** = [`X402Binding`](#x402binding) | [`MppBinding`](#mppbinding) | *typeof* [`paymentRequest`](https://lcp.integraledger.com/reference/api/ack#paymentrequest) | *typeof* [`delegated`](https://lcp.integraledger.com/reference/api/acp#delegated) | *typeof* [`undelegated`](https://lcp.integraledger.com/reference/api/acp#undelegated) | *typeof* [`checkoutMandate`](https://lcp.integraledger.com/reference/api/ap2#checkoutmandate) | *typeof* [`viAutonomous`](https://lcp.integraledger.com/reference/api/card#viautonomous-1) | *typeof* [`viImmediate`](https://lcp.integraledger.com/reference/api/card#viimmediate-1) | *typeof* [`sellerReference`](https://lcp.integraledger.com/reference/api/card#sellerreference) | *typeof* [`visaTap`](https://lcp.integraledger.com/reference/api/card#visatap) | *typeof* [`bookingAp2Mandate`](https://lcp.integraledger.com/reference/api/ucp#bookingap2mandate) | *typeof* [`bookingUnsigned`](https://lcp.integraledger.com/reference/api/ucp#bookingunsigned) | *typeof* [`ap2Mandate`](https://lcp.integraledger.com/reference/api/ucp#ap2mandate) | *typeof* [`unsigned`](https://lcp.integraledger.com/reference/api/ucp#unsigned-1) & [`PushMode`](#pushmode) & [`CarrierAfterH`](#carrierafterh) & [`TxSpelling`](#txspelling) A pairing of protocol, scheme and rail. *** ### CoreRefusal > **CoreRefusal** = `object` #### Properties | Property | Type | | ---------- | ------------------------------------------------------------------------------------------------------------------------------------------------------- | | `code` | `"core/slot-name"` \| `"core/slot-reserved"` \| `"core/slot-duplicate"` \| `"core/content-not-json"` \| `"core/binding-not-json"` \| `"core/too-large"` | | `refused` | `true` | *** ### Json > **Json** = `string` | `number` | `boolean` | `null` | readonly [`Json`](#json)\[] | \{\[`k`: `string`]: [`Json`](#json); } A JSON value. Numbers in a binding value must be safe integers. *** ### MppBinding > **MppBinding** = *typeof* [`MPP_BINDINGS`](https://lcp.integraledger.com/reference/api/mpp#mpp_bindings)\[`number`] An MPP pairing of intent and method. *** ### PairingId > **PairingId** = [`Binding`](#binding)\[`"id"`] *** ### PairingOn > **PairingOn**\<`S`> = `Extract`\<[`PairingId`](#pairingid), `` `${S}/${string}` ``> The pairing ids of one surface. #### Type Parameters | Type Parameter | | ----------------------------------- | | `S` *extends* [`Surface`](#surface) | *** ### Presented > **Presented** = [`PresentedOn`](#presentedon)\[[`Surface`](#surface)] What the buyer presents as payment. *** ### Refusal > **Refusal** = `object` A refusal returned as a value. `code` is `/`. #### Properties | Property | Type | | ---------- | -------- | | `code` | `string` | | `refused` | `true` | *** ### Surface > **Surface** = keyof [`PresentedOn`](#presentedon) The surfaces: a pairing id's first "/" segment. *** ### X402Binding > **X402Binding** = *typeof* [`exactEip3009`](https://lcp.integraledger.com/reference/api/x402#exacteip3009) | *typeof* [`authCaptureEip3009`](https://lcp.integraledger.com/reference/api/x402#authcaptureeip3009) | *typeof* [`authCapturePermit2`](https://lcp.integraledger.com/reference/api/x402#authcapturepermit2) | *typeof* [`batchCloudflare`](https://lcp.integraledger.com/reference/api/x402-batch-settlement#batchcloudflare) | *typeof* [`batchEvm`](https://lcp.integraledger.com/reference/api/x402-batch-settlement#batchevm) | *typeof* [`batchSvm`](https://lcp.integraledger.com/reference/api/x402-batch-settlement#batchsvm) | *typeof* [`exactAvm`](https://lcp.integraledger.com/reference/api/avm#exactavm) | *typeof* [`exactAptos`](https://lcp.integraledger.com/reference/api/aptos#exactaptos) | *typeof* [`exactCardano`](https://lcp.integraledger.com/reference/api/cardano#exactcardano) | *typeof* [`exactCasper`](https://lcp.integraledger.com/reference/api/casper#exactcasper) | *typeof* [`exactCcd`](https://lcp.integraledger.com/reference/api/ccd#exactccd) | *typeof* [`exactErc7710`](https://lcp.integraledger.com/reference/api/x402#exacterc7710) | *typeof* [`exactErc7710Salt`](https://lcp.integraledger.com/reference/api/x402#exacterc7710salt) | *typeof* [`exactPermit2`](https://lcp.integraledger.com/reference/api/x402#exactpermit2) | *typeof* [`exactHedera`](https://lcp.integraledger.com/reference/api/hedera#exacthedera) | *typeof* [`exactHederaExecutor`](https://lcp.integraledger.com/reference/api/hedera#exacthederaexecutor) | *typeof* [`exactLnbtc`](https://lcp.integraledger.com/reference/api/lightning#exactlnbtc) | *typeof* [`exactLnbtcNamed`](https://lcp.integraledger.com/reference/api/lightning#exactlnbtcnamed) | *typeof* [`exactNear`](https://lcp.integraledger.com/reference/api/near#exactnear) | *typeof* [`exactPolkadotRemark`](https://lcp.integraledger.com/reference/api/polkadot#exactpolkadotremark) | *typeof* [`exactSvm`](https://lcp.integraledger.com/reference/api/x402-exact-solana#exactsvm) | *typeof* [`exactStarknet`](https://lcp.integraledger.com/reference/api/starknet#exactstarknet) | *typeof* [`exactStellar`](https://lcp.integraledger.com/reference/api/x402-exact-stellar#exactstellar) | *typeof* [`exactSui`](https://lcp.integraledger.com/reference/api/sui#exactsui) | *typeof* [`exactTronMemo`](https://lcp.integraledger.com/reference/api/tron#exacttronmemo) | *typeof* [`exactTvm`](https://lcp.integraledger.com/reference/api/tvm#exacttvm) | *typeof* [`exactXrpl`](https://lcp.integraledger.com/reference/api/x402-exact-xrpl#exactxrpl) | *typeof* [`uptoPermit2`](https://lcp.integraledger.com/reference/api/x402#uptopermit2) | *typeof* [`uptoSvm`](https://lcp.integraledger.com/reference/api/x402-upto-solana#uptosvm) An x402 pairing of scheme and rail. ## Variables ### BINDINGS > `const` **BINDINGS**: readonly [`Binding`](#binding)\[] Every pairing this package implements. *** ### MAX\_JSON\_DEPTH > `const` **MAX\_JSON\_DEPTH**: `64` = `64` The deepest nesting of arrays and objects in any JSON this package writes or reads. ## Functions ### assemble() > **assemble**(`id`, `binding`, `content`, `limits?`): `Promise`\<[`CoreRefusal`](#corerefusal) | \{ `atrHash`: `` `0x${string}` ``; `bytes`: `Uint8Array`; }> Writes the ATR's bytes and hashes them. The same inputs always give the same bytes. Every problem with the inputs is returned as a refusal. #### Parameters | Parameter | Type | | ------------------ | ------------------------------------------------------------------ | | `id` | `string` | | `binding` | readonly \[`string`, [`Json`](#json)] | | `content` | readonly readonly \[`string`, `Uint8Array`\<`ArrayBufferLike`>]\[] | | `limits?` | \{ `maxBytes?`: `number`; } | | `limits.maxBytes?` | `number` | #### Returns `Promise`\<[`CoreRefusal`](#corerefusal) | \{ `atrHash`: `` `0x${string}` ``; `bytes`: `Uint8Array`; }> *** ### canonicalJson() > **canonicalJson**(`v`): `string` | [`CoreRefusal`](#corerefusal) The RFC 8785 form of `v`: object members sorted by the UTF-16 code units of their names, recursively, and every primitive written as `JSON.stringify` writes it. Refuses what `digestJson` refuses. #### Parameters | Parameter | Type | | --------- | --------------- | | `v` | [`Json`](#json) | #### Returns `string` | [`CoreRefusal`](#corerefusal) *** ### canonicalTx() > **canonicalTx**(`binding`, `tx`): `string` A transaction id as a record keeps it: the pairing's `txId`, where it has one, else the id unchanged. #### Parameters | Parameter | Type | | --------- | ------------------------------------ | | `binding` | [`Binding`](#binding) \| `undefined` | | `tx` | `string` | #### Returns `string` *** ### digestJson() > **digestJson**(`v`): `Promise`\<`` `0x${string}` `` | [`CoreRefusal`](#corerefusal)> SHA-256 over the RFC 8785 form of `v`. Refuses a value deeper than 64 levels, a non-finite number, a string with an unpaired surrogate, or anything that is not a JSON value. #### Parameters | Parameter | Type | | --------- | --------------- | | `v` | [`Json`](#json) | #### Returns `Promise`\<`` `0x${string}` `` | [`CoreRefusal`](#corerefusal)> *** ### fromLcpString() > **fromLcpString**(`s`): `` `0x${string}` `` | `null` Decodes `lcp:sha256:0x…`, returning the lowercase hash, or null for anything else. #### Parameters | Parameter | Type | | --------- | -------- | | `s` | `string` | #### Returns `` `0x${string}` `` | `null` *** ### fromLegalContext() > **fromLegalContext**(`o`): \{ `h`: `` `0x${string}` ``; `url`: `string`; } | `null` Decodes the structured form: `type` "sha256", a 32-byte hash, and an `https://` link in either spelling. Returns the lowercase hash and the link, or null for anything else, including two spellings that disagree. Other members are ignored. #### Parameters | Parameter | Type | | --------- | --------- | | `o` | `unknown` | #### Returns \{ `h`: `` `0x${string}` ``; `url`: `string`; } | `null` *** ### fromRawBytes() > **fromRawBytes**(`b`): `` `0x${string}` `` | `null` The lowercase hash of exactly 32 raw bytes, or null. #### Parameters | Parameter | Type | | --------- | ------------ | | `b` | `Uint8Array` | #### Returns `` `0x${string}` `` | `null` *** ### hash() > **hash**(`bytes`): `Promise`\<`` `0x${string}` ``> SHA-256 over the bytes as given, as `0x` and lowercase hex. #### Parameters | Parameter | Type | | --------- | ------------ | | `bytes` | `Uint8Array` | #### Returns `Promise`\<`` `0x${string}` ``> *** ### hashEquals() > **hashEquals**(`a`, `b`): `boolean` True when `a` and `b` are each `0x` and 64 hex digits, in either case, and decode to the same 32 bytes (LCP §2.5). Anything else is false. #### Parameters | Parameter | Type | | --------- | -------- | | `a` | `string` | | `b` | `string` | #### Returns `boolean` *** ### isHashWithNonHttpsLink() > **isHashWithNonHttpsLink**(`info`): `boolean` True for a structured form's inner object that `fromLegalContext` would decode except that its one link, in either spelling, is a link of another scheme (`isOtherSchemeLink`). #### Parameters | Parameter | Type | | --------- | --------- | | `info` | `unknown` | #### Returns `boolean` *** ### isHttpsLink() > **isHttpsLink**(`s`): `s is string` The one https-link rule. The raw string holds no whitespace, control character or backslash; it parses as an absolute URL; its scheme is `https`, compared case-insensitively (RFC 3986 §3.1); its authority has a host, a DNS name or an IP literal, and no userinfo. #### Parameters | Parameter | Type | | --------- | --------- | | `s` | `unknown` | #### Returns `s is string` *** ### isOtherSchemeLink() > **isOtherSchemeLink**(`s`): `s is string` True for a string of at most 2048 characters that parses as an absolute URL whose scheme is not `https`: the one failing link refused as `link-not-https`. Every other failing link is `legal-context-malformed`. #### Parameters | Parameter | Type | | --------- | --------- | | `s` | `unknown` | #### Returns `s is string` *** ### jsonWithinDepth() > **jsonWithinDepth**(`text`): `boolean` True when no array or object in JSON text is nested more than `MAX_JSON_DEPTH` deep. Brackets inside strings are skipped; nothing else about the text is checked. #### Parameters | Parameter | Type | | --------- | -------- | | `text` | `string` | #### Returns `boolean` *** ### newAtrId() > **newAtrId**(): `string` A random RFC 9562 version 4 UUID, lowercase. #### Returns `string` *** ### pairingOf() > **pairingOf**(`option`): [`PairingOn`](#pairingon)\<`"x402"`> | `undefined` The x402 pairing that serves an option: a Lightning option's by `lnbtcPairingOf`, which names `x402/exact/lnbtc` for an option whose invoice is not yet written; else the first x402 pairing in `BINDINGS` whose `read` offers it, on a document holding that option alone. Undefined when none does. #### Parameters | Parameter | Type | | --------- | ---------------------------------------------------------------- | | `option` | [`PaymentRequirements`](https://lcp.integraledger.com/reference/api/x402#paymentrequirements) | #### Returns [`PairingOn`](#pairingon)\<`"x402"`> | `undefined` *** ### pairingsOfPlaced() > **pairingsOfPlaced**(`c`): readonly [`MppPairing`](https://lcp.integraledger.com/reference/api/mpp#mpppairing)\[] The pairings a placed challenge offers: `pairingsOf` over the challenge with its `opaque` removed, so the LCP members `place` wrote are not read as an occupied carrier. None when the challenge does not read. #### Parameters | Parameter | Type | | --------- | ------------------------------------------------- | | `c` | [`MppChallenge`](https://lcp.integraledger.com/reference/api/mpp#mppchallenge) | #### Returns readonly [`MppPairing`](https://lcp.integraledger.com/reference/api/mpp#mpppairing)\[] *** ### parseJson() > **parseJson**(`text`): `unknown` The value of JSON text nested at most `MAX_JSON_DEPTH` deep; undefined for text that is deeper or is not JSON. #### Parameters | Parameter | Type | | --------- | -------- | | `text` | `string` | #### Returns `unknown` *** ### toLcpString() > **toLcpString**(`h`): `string` LCP §8.1 string form: `lcp:sha256:0x…`. Throws TypeError when `h` is not a 32-byte hash. #### Parameters | Parameter | Type | | --------- | ------------------- | | `h` | `` `0x${string}` `` | #### Returns `string` *** ### toLegalContext() > **toLegalContext**(`h`, `url`, `spelling?`): `object` LCP §8.1 structured form, with the link beside the digest. `spelling` "snake" writes `legal_context_url`. Throws TypeError when `h` is not a 32-byte hash or `url` is not an `https://` URL. #### Parameters | Parameter | Type | Default value | | ---------- | ---------------------- | ------------- | | `h` | `` `0x${string}` `` | `undefined` | | `url` | `string` | `undefined` | | `spelling` | `"camel"` \| `"snake"` | `"camel"` | #### Returns `object` | Name | Type | | --------------------------------- | ------------------- | | `legalContext` | `object` | | `legalContext.legal_context_url?` | `string` | | `legalContext.legalContextUrl?` | `string` | | `legalContext.type` | `"sha256"` | | `legalContext.value` | `` `0x${string}` `` | *** ### toRawBytes() > **toRawBytes**(`h`): `Uint8Array` The raw 32 bytes of a hash. Throws TypeError when `h` is not a 32-byte hash. #### Parameters | Parameter | Type | | --------- | ------------------- | | `h` | `` `0x${string}` `` | #### Returns `Uint8Array` ## References ### LcpPattern Re-exports [LcpPattern](https://lcp.integraledger.com/reference/api/x402#lcppattern)