> ## Documentation Index
> Fetch the complete documentation index at: https://docs.hashlock.markets/llms.txt
> Use this file to discover all available pages before exploring further.

# Set a settlement address

> Set your receive (payout) / refund address for a leg. Bitcoin: the compressed pubkey (hex) — the P2WSH is derived once both sides are set. Required before funding. An address that RECEIVES money — the payout one, and on Bitcoin and Solana the refund one too — must be a wallet this account signed in with, or proved from a signed-in wallet session on the web (for Bitcoin, the pubkey of such an address). A proof made with an API key (POST /v1/wallets/<chain>) widens what you can trade but does not count here, so a leaked key cannot redirect your money.



## OpenAPI

````yaml POST /v1/swaps/{id}/address
openapi: 3.1.0
info:
  title: Hashlock Markets API
  version: 1.0.0
  description: >-
    Guides, concepts and a quickstart: https://docs.hashlock.markets


    Non-custodial cross-chain atomic swaps (BTC ↔ EVM / TRON / Solana) via
    sealed RFQ + HTLC. Makers and takers share these endpoints. Authenticate
    with an API key: `Authorization: Bearer hk_...`.


    **Wallets first.** An order that GIVES an asset requires a proven wallet on
    that asset's chain, and your key starts with only the address its account
    signed in with. `GET /v1/me` lists both what each chain's `login` address is
    and what you have `proven`; `POST /v1/wallets/{evm|tron|solana|bitcoin}`
    proves another by signature — Bitcoin included, on a BIP-322 one. A proof
    adds trading reach and nothing else: it never becomes the account's payout
    identity, which only a wallet session can change — so a key alone cannot
    redirect anyone's money. The message you sign for it must say `link this
    wallet` and carry a nonce from `GET /v1/wallets/nonce`; that nonce is not a
    login nonce, so the signature you collect is not a session for that wallet's
    account.


    **Rate limits.** Every response carries `RateLimit-Limit`,
    `RateLimit-Remaining` and `RateLimit-Reset` (seconds). Over the limit
    returns `429` with `Retry-After`.


    **Idempotency.** Send an `Idempotency-Key` header on any POST to make
    retries safe: the operation runs once and the same response is replayed
    (with `Idempotency-Replayed: true`). Reusing a key with a different body
    returns `422`. Keys are remembered for 24h — except a `504`, which is a read
    of ours running out of time: on the builders nothing happened, and on
    `/tx/broadcast` we cannot tell — so either way a retry with the same key
    really retries.


    **Custody-agnostic settlement.** The fund/claim/refund endpoints return
    UNSIGNED transactions; you sign with your own key/HSM and submit via
    `/v1/tx/broadcast`. The server never holds your keys.


    ---


    ## Maker feed (WebSocket)


    Polling `GET /v1/rfqs` will not win you flow. `wss://<host>/v1/ws` — the
    host you selected above — streams every request-for-quote you are eligible
    for, and takes your quotes back over the same socket.


    **Handshake.** Connect, then send your key as the first frame. Nothing else
    is accepted until you do:


    ```json

    { "apiKey": "hk_test_..." }

    ```


    The key needs the `maker` scope (`GET /v1/me` shows what yours has). You get
    a snapshot, then a readiness marker:


    ```json

    { "type": "snapshot", "rfqs": [ ... ] }

    { "type": "ready" }

    ```


    The snapshot is the **public** book only, and at most **100** entries,
    newest first. If you need more than that, page `GET /v1/rfqs?cursor=…` after
    connecting. An RFQ created while the snapshot was being built may appear
    both in it and in the stream that follows — frames carry the rfq id, so key
    on it and the duplicate is a no-op.


    **The stream.** Two kinds, and only two:


    ```json

    { "type": "rfq", "kind": "created",   "rfq": { ... } }

    { "type": "rfq", "kind": "cancelled", "rfq": { ... } }

    ```


    An RFQ also leaves the book when it **expires** or is **agreed** with
    another maker, and neither emits a frame. A book you maintain purely from
    the stream therefore drifts: it keeps orders nobody can take any more, and
    quoting into one is rejected. Reconcile with a fresh `snapshot` (reconnect)
    or check `GET /v1/rfqs/{id}` before committing to a price.


    **What reaches you.** Public RFQs, plus private ones addressed to an address
    on your account. Matching follows each encoding: EVM hex and bech32
    (`bc1…`/`tb1…`) compare case-insensitively, base58check (TRON, legacy
    Bitcoin) does not — there the case of a character is part of the address.
    Never your own orders — neither in the snapshot nor in the stream. Note the
    asymmetry: **private orders arrive only on the live stream.** They are
    link-only by design, so they are absent from the snapshot and from `GET
    /v1/rfqs`, and there is no endpoint that lists the ones addressed to you. A
    private order sent while your socket was down is not recoverable — if you
    trade private flow, stay connected.


    **Quoting.** Send the quote down the same socket; no HTTP round-trip, no
    second authentication. `quoteAmount` is in base units, as everywhere else in
    this API:


    ```json

    { "quote": { "rfqId": "…", "quoteAmount": "1500000000" } }

    → { "type": "quoted", "rfqId": "…", "threadId": "…" }

    ```


    The `threadId` is a negotiation thread: `GET /v1/threads/{id}` and the
    propose/accept endpoints take it from there. `POST /v1/rfqs/{id}/quotes`
    does the same thing over REST if you prefer.


    **Errors** arrive as `{ "type": "error", "error": "…" }` and do not close
    the socket.


    **Operating it.** There is no heartbeat and no resume: detect a dead socket
    yourself and reconnect. The fresh `snapshot` is your recovery for the public
    book, with the two limits above — 100 entries, and no private orders.
    Nothing is replayed, so this socket is not a settlement log. For that
    register a webhook (`POST /v1/webhooks`): the feed tells you what to quote,
    webhooks tell you what happened to your swaps.


    **Webhook signature.** `x-hashlock-signature: sha256=<hex>` is HMAC-SHA256
    over `<timestamp>.<body>` with your webhook secret; the timestamp is in
    `x-hashlock-timestamp`. Verify before trusting a delivery, and reply 2xx.


    **Webhook events.** `quote.created`, `swap.agreed`, `swap.funded`,
    `secret.revealed`, `swap.settled`, `swap.refunded` — subscribe to none and
    you get all of them. `POST /v1/webhooks/{id}/ping` also delivers a `ping`
    event, so handle an unknown `type` by returning 2xx rather than erroring.


    **Webhook delivery is best-effort, not durable.** A non-2xx or a timeout is
    retried after 15s, 30s, 60s, 120s and 240s — **6 attempts over 7m45s** — and
    is then dropped; there is no redelivery endpoint and no delivery log beyond
    `lastStatus` on `GET /v1/webhooks`. If your receiver is down longer than
    that you will lose events, so reconcile against `GET /v1/swaps/{id}` — that
    is the authoritative state — rather than treating the webhook as the record.
servers:
  - url: https://api.hashlock.markets
    description: production
security:
  - ApiKey: []
paths:
  /v1/swaps/{id}/address:
    post:
      summary: Set your receive (payout) / refund address for a leg
      description: >-
        Set your receive (payout) / refund address for a leg. Bitcoin: the
        compressed pubkey (hex) — the P2WSH is derived once both sides are set.
        Required before funding. An address that RECEIVES money — the payout
        one, and on Bitcoin and Solana the refund one too — must be a wallet
        this account signed in with, or proved from a signed-in wallet session
        on the web (for Bitcoin, the pubkey of such an address). A proof made
        with an API key (POST /v1/wallets/<chain>) widens what you can trade but
        does not count here, so a leaked key cannot redirect your money.
      operationId: postSwapsByIdAddress
      parameters:
        - name: id
          in: path
          required: true
          schema:
            type: string
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
                - chain
                - address
              properties:
                chain:
                  type: string
                address:
                  type: string
                leg:
                  type: string
                  enum:
                    - a
                    - b
                  description: required only when both legs of the swap are on `chain`
            example:
              chain: <a chain of this swap>
              address: <your payout address on that chain>
      responses:
        '200':
          description: ok
          content:
            application/json:
              schema:
                type: object
                properties:
                  swap:
                    $ref: '#/components/schemas/Swap'
        '400':
          description: error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '504':
          description: >-
            a chain or explorer read of ours ran out of time — nothing was
            changed; retry (an Idempotency-Key does not remember a 504)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
components:
  schemas:
    Swap:
      type: object
      properties:
        id:
          type: string
        status:
          type: string
    Error:
      type: object
      properties:
        error:
          type: string
      required:
        - error
  securitySchemes:
    ApiKey:
      type: http
      scheme: bearer
      description: An API key (hk_live_… / hk_test_…) with read/taker/maker scopes.

````