Build ready-to-sign transaction bundles for any Baseline action over plain HTTP.

Base URL: https://api.baseline.markets

The actions API turns any Baseline protocol action — launch a token, buy, sell, stake (deposit / withdraw / claim), borrow, repay — into a wallet_sendCalls-compatible (ERC-5792) transaction bundle over plain HTTP. It is the fastest way to integrate Baseline into a frontend: no SDK dependency, no contract knowledge, no quote or approval logic on your side.

The API prepares and validates; your user's wallet signs and pays. It never holds keys, signs, or submits transactions.

Discovery

GET /v1/actions (no auth) returns an OpenAPI 3.1 spec describing every endpoint, with request schemas generated from the same validators that guard the routes, and the live per-chain approved-reserve registry under x-baseline-chains. Also served at /v1/actions/openapi.json.

Integrating a frontend

Three steps, all stateless:

1. Authenticate (SIWE)

GET  /v1/auth/nonce                     → { nonce }
POST /v1/auth/verify                    → { token, address, expiresAt }
     { message, signature }

Build an EIP-4361 message with the nonce, have the wallet sign it (personal_sign), and exchange it for a JWT. Send the JWT as Authorization: Bearer <jwt> afterwards.

2. Build the calls

POST /v1/actions/build

{
  "type": "buy",
  "chainId": 8453,
  "bToken": "0x…",
  "exactSide": "in",
  "amount": "0.5",
  "slippagePct": "1"
}

The config is a discriminated union on type: launch, buy, sell, deposit, withdraw, claim, borrow, repay. Amounts are human-unit decimal strings — BToken amounts in whole tokens (18 decimals), reserve amounts in whole reserve units.

The response is an executable artifact:

{
  "artifact": {
    "type": "buy",
    "chainId": 8453,
    "account": "0x…",
    "calls": [
      { "to": "0x…", "data": "0x…" },
      { "to": "0x…", "data": "0x…" }
    ],
    "summary": {
      "exactSide": "in",
      "exactAmount": "500000000000000000",
      "quotedAmount": "1000000000000000000000",
      "limitAmount": "990000000000000000000"
    },
    "quotedAt": "2026-07-08T00:00:00.000Z"
  }
}

Trades are quoted on-chain at build time; the swap's limit is derived from slippagePct.
Required ERC-20 approvals are prepended to calls, so the bundle executes as-is — no separate approval step in your UI.
Launch artifacts include the precomputed bToken address, known before anything is signed.
summary carries the raw parsed amounts for your review screen.
Quotes go stale: rebuild the artifact if meaningful time passes between build and signing (quotedAt tells you when state was read).

3. Execute

Send artifact.calls in order from the authenticated wallet — wallet_sendCalls (EIP-5792) as one bundle, or sequential eth_sendTransaction. Every call must succeed. Simulate client-side before signing for pre-flight protection.

Nothing is persisted server-side; there is no record to manage.

Reads

The actions API constructs transactions only. For token lists, prices, balances, and pool state, use the GraphQL API at /graphql and the REST read endpoints.

Actions API