Fees and costs

Writes can cost money. This page is about showing those costs in your UI.

Today’s documented ledger is Infinite Mainnet (EVM). Cost kinds such as bridge and multi-ledger gas lines are contract shapes for when a quote path spans ledgers — they may be absent on single-ledger Infinite Mainnet quotes.

Two different things

Question	Answer
Do writes cost something?	Yes — network gas and Nutrimatic’s service fee apply on writes. Swaps can also include market / bridge costs.
Does the SDK give you a cost list before you execute?	Only for swaps. Call `routing.quote`; the quote includes a `costs` array you can show on screen.

routing.quote is the method that asks for a swap quote (amounts, slippage, expiry). That quote’s costs field is the breakdown for your “you will pay…” UI.

For liquidity, approve, stake, and farm, those writes can still charge gas and the service fee when they run, but the SDK does not return a costs list beforehand. Your UI can confirm the action and follow status; it does not get a swap-style cost breakdown for those calls.

Cost lines on a swap quote

Each entry in Quote.costs has kind, amount, instrumentId, and sometimes estimated.

Field	Type	Description
`kind`	`QuoteCostKind`	What this line is — see kinds below.
`amount`	`string`	Display decimal in that instrument’s units (same style as other write amounts).
`instrumentId`	`InstrumentId`	Asset this line is denominated in. Resolve the symbol via the catalog if your UI needs a ticker.
`estimated`	`boolean`	Optional. When `true`, treat `amount` as approximate until the write confirms on-chain. Common for `gas`; sometimes for `bridge`.

`kind`	What it is	Paid in
`gas`	Network execution cost	Ledger native
`trade`	Market / swap fee for the route	That line’s `instrumentId` (often a trade asset)
`bridge`	Extra cost when the plan moves value across ledgers	That line’s `instrumentId`
`service`	Fixed Nutrimatic fee for the write	Ledger native

Example — `Quote.costs` on a swap

[
  {
    "kind": "trade",
    "amount": "0.0045",
    "instrumentId": "evm:421018:instrument:42"
  },
  {
    "kind": "gas",
    "amount": "0.0007",
    "instrumentId": "evm:421018:instrument:42",
    "estimated": true
  },
  {
    "kind": "service",
    "amount": "0.0001",
    "instrumentId": "evm:421018:instrument:42"
  }
]

When each kind appears (swap quotes)

Kind	On a swap quote
`gas`	Always; usually `estimated: true`
`trade`	Always
`service`	Always
`bridge`	Only when the quote `path` needs a cross-ledger step

A successful swap quote includes the lines that apply — show those; if a kind is absent, it does not apply to that quote.
Do not sum lines that use different instrumentIds into one number — show each line with its own asset (or convert in your UI if you have prices).

Multi-ledger quotes

When a quote’s path spans more than one ledger:

You may see more than one gas or service line — one per ledger involved, each in that ledger’s native instrument.
A bridge line appears when there is a cross-ledger step; its instrumentId is the asset that line is charged in.
Quote.ledger is still the primary ledger for the quote; cost lines carry their own instrumentId (and thus ledger) per line.

Service fee

Fixed per ledger — same amount for all writes on that chain.
Always in that ledger’s native instrument.

Amounts can differ across ledgers: native tokens vary a lot in price, so each ledger’s fee is set to stay modest in real terms.

This small fee helps us keep building Nutrimatic with care — so you can keep shipping on a product we love making.

Infinite Mainnet (evm:421018): 0.0001 42 on every write. See Ledgers.

Goal	Start here
Get a swap quote that includes `costs`	Swaps — routing.quote
Multi-step path fees	Settlement — Path
`QuoteCost` shape	Types — QuoteCost
Write overview	Write operations
Liquidity / stake / farm (no pre-execute `costs` list)	Liquidity · Staking · Farming

Write operations Swaps