# Developers · Integra

> The published packages and their documentation: the seller side, the buyer’s gate, MCP tools and the seller door.

URL: https://integraledger.com/developers

Developers

## Open packages, and their documentation.

Everything this site explains is in public packages you can install and read. The seller side is deterministic and small at its core: it holds no key, signs nothing and calls no network on its own. [Source: @integraledger/lcp README⁠ (opens in a new tab)](https://github.com/IntegraLedger/integra-protocol/blob/66274bf/lcp/README.md) · [Source: @integraledger/lcp: what it guarantees⁠ (opens in a new tab)](https://github.com/IntegraLedger/integra-protocol/blob/66274bf/lcp/README.md#what-it-guarantees-and-what-it-does-not)

**Sources (2)**

[@integraledger/lcp README⁠ (opens in a new tab)](https://github.com/IntegraLedger/integra-protocol/blob/66274bf/lcp/README.md) · [@integraledger/lcp: what it guarantees⁠ (opens in a new tab)](https://github.com/IntegraLedger/integra-protocol/blob/66274bf/lcp/README.md#what-it-guarantees-and-what-it-does-not)

### The packages

Each package’s name, version and description below is read from the package itself when the site is built.

- @integraledger/lcp Apache-2.0

  Assemble and hash an Agentic Transaction Record (ATR), and carry the hash in x402, MPP, AP2, ACP, UCP, ACK and card payments across chains and rails, and in A2A task metadata.

  [npm⁠ (opens in a new tab)](https://www.npmjs.com/package/@integraledger/lcp/v/0.3.0) [Source⁠ (opens in a new tab)](https://github.com/IntegraLedger/integra-protocol)
- @integraledger/terms Apache-2.0

  Buyer gate: compare the ATR hash with the served bytes, and build the payment with that hash, before signing.

  [npm⁠ (opens in a new tab)](https://www.npmjs.com/package/@integraledger/terms/v/0.2.0) [Source⁠ (opens in a new tab)](https://github.com/IntegraLedger/integra-agentic-terms)
- @integraledger/terms-mcp Apache-2.0

  The buyer gate's operations as MCP tools, with a skill for the agent that uses them.

  [npm⁠ (opens in a new tab)](https://www.npmjs.com/package/@integraledger/terms-mcp/v/0.2.0) [Source⁠ (opens in a new tab)](https://github.com/IntegraLedger/integra-agentic-terms)
- @integraledger/agentic-connectors Apache-2.0

  The seller door's contract: the OpenAPI 3.1 document, TypeScript types, refusal table and vectors a connector speaks to issue an ATR, claim a payment and report a settlement.

  [npm⁠ (opens in a new tab)](https://www.npmjs.com/package/@integraledger/agentic-connectors/v/0.2.0) [Source⁠ (opens in a new tab)](https://github.com/IntegraLedger/integra-agentic-connectors)
- @integraledger/profile-facilitator Apache-2.0

  An x402 facilitator for the LCP profiles x402/exact/tron/lcp-trc20-memo and x402/exact/polkadot/lcp-assets-remark: verifies and settles payments whose signed transaction carries the ATR hash.

  [npm⁠ (opens in a new tab)](https://www.npmjs.com/package/@integraledger/profile-facilitator/v/0.2.0) [Source⁠ (opens in a new tab)](https://github.com/IntegraLedger/integra-agentic-connectors)
- integraledger-terms

  The buyer’s gate for Python, passing the same vectors as the TypeScript gate. [Source: integraledger-terms (Python) README⁠ (opens in a new tab)](https://github.com/IntegraLedger/integra-agentic-terms/blob/c094847/agentic-terms-py/README.md)

  [PyPI⁠ (opens in a new tab)](https://pypi.org/project/integraledger-terms/)

**Sources (1)**

[integraledger-terms (Python) README⁠ (opens in a new tab)](https://github.com/IntegraLedger/integra-agentic-terms/blob/c094847/agentic-terms-py/README.md)

#### The standard

Each version below is the one the site was built against, read from the package’s own `package.json`.

**@integraledger/lcp**

0.3.0

**@integraledger/terms**

0.2.0

**@integraledger/terms-mcp**

0.2.0

**@integraledger/agentic-connectors**

0.2.0

**@integraledger/profile-facilitator**

0.2.0

#### The code

Compiled against the published packages when the site is built.

Install

```
npm install @integraledger/lcp
npm install @integraledger/terms
npm install @integraledger/terms-mcp
npm install @integraledger/agentic-connectors
npm install @integraledger/profile-facilitator
pip install integraledger-terms
```

### What `@integraledger/lcp` covers

**pairings**

67

**protocol surfaces**

7

**rails and processors**

21

**recoverable from the chain alone**

23

A pairing is one payment protocol, scheme and rail. Each declares where the ATR hash rides — the unique fingerprint of the agreement’s Agentic Transaction Record (ATR) — and what a payment through it proves. [Source: lcp docs: pairings reference⁠ (opens in a new tab)](https://github.com/IntegraLedger/integra-protocol/blob/66274bf/docs/reference/pairings.md)

**Sources (1)**

[lcp docs: pairings reference⁠ (opens in a new tab)](https://github.com/IntegraLedger/integra-protocol/blob/66274bf/docs/reference/pairings.md)

#### The standard

The package’s registry, `BINDINGS`, holds every pairing with its pattern record. This lists the pairings whose ATR hash anyone can read back from the settled transaction alone. [Source: lcp docs: recovering H from the chain alone⁠ (opens in a new tab)](https://github.com/IntegraLedger/integra-protocol/blob/66274bf/docs/guides/rails.md#recovering-h-from-the-chain-alone)

#### The code

Compiled against the published packages when the site is built.

Every pairing, from the registry

src/snippets/registry.ts

```
// The package's registry holds every pairing with its pattern record: here, the pairings whose fingerprint anyone can
// read back from the settled transaction alone.
import { BINDINGS } from '@integraledger/lcp';

export const recoverable = BINDINGS.filter((b) => b.pattern.zeroPartyRecoverable).map((b) => b.id);
```

### Read the documentation

- [Concepts, guides and reference for `@integraledger/lcp` ⁠ (opens in a new tab)](https://github.com/IntegraLedger/integra-protocol/tree/66274bf/docs)
- [The seller guide: assemble, advertise, check the payment, read the settlement⁠ (opens in a new tab)](https://github.com/IntegraLedger/integra-protocol/blob/66274bf/docs/guides/seller.md)
- [The buyer guide: compare, then build and sign, then finish⁠ (opens in a new tab)](https://github.com/IntegraLedger/integra-protocol/blob/66274bf/docs/guides/buyer.md)
- [Rails: where the ATR hash rides on each chain and payment network⁠ (opens in a new tab)](https://github.com/IntegraLedger/integra-protocol/blob/66274bf/docs/guides/rails.md)
- [Agentic checkouts: ACP, UCP, AP2, ACK, card networks and A2A⁠ (opens in a new tab)](https://github.com/IntegraLedger/integra-protocol/blob/66274bf/docs/guides/checkouts.md)
- [The pairings reference, with each pairing’s proof sentence⁠ (opens in a new tab)](https://github.com/IntegraLedger/integra-protocol/blob/66274bf/docs/reference/pairings.md)
- [The buyer’s gate: `@integraledger/terms` ⁠ (opens in a new tab)](https://github.com/IntegraLedger/integra-agentic-terms/blob/c094847/agentic-terms/README.md)
- [The seller door’s contract: `@integraledger/agentic-connectors` ⁠ (opens in a new tab)](https://github.com/IntegraLedger/integra-agentic-connectors/blob/48500fe/contract/README.md)

### Read the site at technical depth

These links open each page at the technical depth: the standard, the data and the code behind each section, and how to check it yourself.

- [The home page, with the ATR’s bytes and the standard’s full example](https://integraledger.com/?for=technical)
- [Every protocol, with each pairing’s record](https://integraledger.com/protocols?for=technical)
- [Every rail, with its reader and entry points](https://integraledger.com/rails?for=technical)
- [The Levels of Trust, with what the packages do at each](https://integraledger.com/levels?for=technical)
- [Payment types: every payment type in the package, where the ATR hash rides and what each proves](https://integraledger.com/payment-types?for=technical)

### The standard

The packages implement the Legal Context Protocol. Its public text, examples and governance are at legalcontextprotocol.org; any implementation, in any language, is welcome. [Source: LCP Abstract⁠ (opens in a new tab)](https://github.com/legal-context-protocol/legal-context-protocol/blob/c8df26d/spec/legal-context-protocol-v1.md#abstract) · [Source: LCP governance⁠ (opens in a new tab)](https://github.com/legal-context-protocol/legal-context-protocol/blob/c8df26d/GOVERNANCE.md)

[Go to legalcontextprotocol.org⁠ (opens in a new tab)](https://legalcontextprotocol.org)

**Sources (2)**

[LCP Abstract⁠ (opens in a new tab)](https://github.com/legal-context-protocol/legal-context-protocol/blob/c8df26d/spec/legal-context-protocol-v1.md#abstract) · [LCP governance⁠ (opens in a new tab)](https://github.com/legal-context-protocol/legal-context-protocol/blob/c8df26d/GOVERNANCE.md)

#### The standard

The public text and its example documents are versioned on GitHub; every LCP § on this site links to the section it cites. [Source: LCP Abstract⁠ (opens in a new tab)](https://github.com/legal-context-protocol/legal-context-protocol/blob/c8df26d/spec/legal-context-protocol-v1.md#abstract) · [Source: LCP examples⁠ (opens in a new tab)](https://github.com/legal-context-protocol/legal-context-protocol/tree/c8df26d/examples)

#### The code

Compiled against the published packages when the site is built.

Read a discovery document as the standard defines it

src/snippets/discovery.ts

```
// An agent, before it transacts: read a service's legal front door and the terms it points to.
import { isRefusal } from '@integraledger/lcp';
import { parse, WELL_KNOWN_PATH } from '@integraledger/lcp/discovery';

export async function legalContext(origin: string) {
  const response = await fetch(new URL(WELL_KNOWN_PATH, origin));
  const read = parse(new Uint8Array(await response.arrayBuffer()));
  if (isRefusal(read)) return read;
  return read.document; // terms, and at higher levels atrHash, acceptanceRequired, disputeResolution…
}
```

### Ready to see your own agreements proved?

Tell us what you sell, buy or carry, and we will show you where the agreement rides in it.

The hosted appliance is free on test networks, with test-network USDC.

[Talk to us](https://integraledger.com/contact)