Make offer (build typed-data)

GET 
/v1/actions/midnight/make

MAKE — step 1 of 2. Build the EIP-712 typed-data for a limit offer at your own rate.

Morpho Midnight is an order-book lender — liquidity is a book of maker offers, not a pool — so there are two ways to interact:

• TAKE (fill existing offers): use the standard lending actions, which route to Midnight automatically for a MORPHO_MIDNIGHT_<id> market. There is no separate "take" endpoint.
  • lend → /v1/actions/lending/deposit — fills the ask side (supply offers)
  • borrow → /v1/actions/lending/borrow — fills the bid side (demand offers)
  • repay / withdraw → /v1/actions/lending/repay · /withdraw
  • Read the live two-sided ladder from /v1/data/lending/latest?includeOffers=true — each order-book market's loan leg carries offers (bids) and lendOffers (asks), best-first, with per-level aprPct, assets, and cumulativeAssets.
• MAKE (post your own limit offer at a chosen rate): the endpoints in this section (/v1/actions/midnight/*) plus /v1/data/lending/orders to list and cancel them.

Make flow (worker-assisted signing):

1. GET /v1/actions/midnight/make → returns typedData, the echoed inputs, and a one-time authorization tx.
2. The maker signs typedData with their wallet (wallet.signTypedData).
3. POST /v1/actions/midnight/finalize with { inputs, signature } → the on-chain transaction that publishes the offer to the Midnight mempool.

If authorization is present and the maker has not yet authorized the ratifier (read isAuthorized on-chain), send that one-time setIsAuthorized transaction before finalizing. The APR you request is snapped to an order-book tick — aprPctSnapped is the exact rate the offer will quote.

Plain-text reference — GET /v1/actions/midnight/make

Parameters

Parameter	In	Type	Required	Description
chainId	query	string	yes	Chain ID (alias: chain). Midnight is Base-only today. See the ChainId schema for the full set of supported chains.
lender	query	string	yes	MORPHO_MIDNIGHT_<id> lender key (the market to post into). See the LenderId schema for the full set of accepted values.
side	query	lend, borrow	yes	lend posts a bid (you lend when taken); borrow posts an ask (you borrow when taken).
aprPct	query	number	yes	Your target APR in percent (alias: rate). Snapped to an order-book tick; see aprPctSnapped in the response.
size	query	string	yes	Offer size in loan-token units (integer wei).
expiry	query	integer	yes	Offer expiry, unix seconds. Must be in the future and ≤ the market maturity.
account	query	string	yes	Maker (offer owner) address.

Response 200

Field	Type	Description
success	True
data	object	Everything the frontend needs to sign and publish a maker offer (step 1 of the make flow). actions is null — the publish transaction is produced by /finalize after signing.
data.typedData	object	EIP-712 typed-data to sign with wallet.signTypedData (bigints serialized as strings — sign the response as-is).
data.inputs	object	Deterministic offer inputs. Returned verbatim by GET /v1/actions/midnight/make; POST them back unchanged to /v1/actions/midnight/finalize alongside the signature so the worker rebuilds the identical offer tree. Any tampering fails on-chain ratification.
data.inputs.chainId	string	EVM chain id, as a decimal string. See the ChainId schema.
data.inputs.lender	string	MORPHO_MIDNIGHT_<id> lender key.
data.inputs.buy	boolean	true = maker BUYS units (a lend offer / bid); false = maker SELLS units (a borrow offer / ask).
data.inputs.tick	string	Order-book tick the APR snapped to.
data.inputs.start	string
data.inputs.expiry	string	Offer expiry, unix seconds.
data.inputs.maxAssets	string	Maker-side size in loan-token units.
data.inputs.maker	string	Maker (offer owner) address.
data.authorization	object	One-time setIsAuthorized(ecrecoverRatifier, true) transaction on the Midnight core. Send FIRST, only if the maker has not authorized the ratifier yet (read isAuthorized on-chain).
data.authorization.to	string
data.authorization.data	string	Informational payload. null when the endpoint only builds calldata.
data.authorization.value	string	Native-token value to send with the transaction, in wei.
data.authorization.ratifier	string
data.aprPctSnapped	number	The exact APR (percent) after tick-snapping — what the offer will actually quote once posted.
data.maturity	number	Market maturity, unix seconds.
actions	null

Example response

{
  "success": true,
  "data": {
    "typedData": {},
    "inputs": {
      "chainId": "8453",
      "lender": "MORPHO_MIDNIGHT_0xABC\u2026",
      "buy": true,
      "tick": "string",
      "start": "0",
      "expiry": "string",
      "maxAssets": "string",
      "maker": "string"
    },
    "authorization": {
      "to": "0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2",
      "data": "0x617ba037000000000000000000000000c02aaa39b2",
      "value": "1000000000000000000",
      "ratifier": "string"
    },
    "aprPctSnapped": 3.49,
    "maturity": 1.0
  }
}

Request

Responses

200

Offer typed-data, echoed inputs, and one-time authorization

400

Validation error

429

Rate limited. Unauthenticated callers share a per-IP budget; send an x-api-key header to lift it. Retry with exponential backoff.

500

Unexpected server error. Safe to retry with backoff.

502

An upstream data source or protocol origin failed (error.code is ORIGIN_FAILED). error.details carries the per-origin status. This is also what a missing or malformed required parameter currently returns, rather than a 400.