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OpenAPI Specification
openapi: 3.2.0
info:
title: Hiro Fees API
version: '1.0'
description: 'Operations tagged Fees across 2 of this provider''s published API definitions: hiro-stacks-blockchain-api-openapi.yaml, hiro-stacks-node-rpc-api-openapi.yaml. Each path carries the servers of the definition it was published in.'
servers:
- url: https://api.hiro.so/
description: mainnet
- url: http://localhost:20443
description: Local Stacks Node
tags:
- name: Fees
description: Read-only endpoints to obtain fee details
paths:
/extended/v1/fee_rate/:
post:
operationId: fetch_fee_rate
summary: Fetch fee rate
tags:
- Fees
description: '**NOTE:** This endpoint is deprecated in favor of Get approximate fees for a given transaction.
Retrieves estimated fee rate.'
requestBody:
content:
application/json:
schema:
title: FeeRateRequest
description: Request to fetch fee for a transaction
type: object
properties:
transaction:
description: A serialized transaction
type: string
required:
- transaction
required: true
description: Request to fetch fee for a transaction
deprecated: true
responses:
'200':
description: Get fee rate information.
content:
application/json:
schema:
title: FeeRate
description: Get fee rate information.
type: object
properties:
fee_rate:
type: integer
required:
- fee_rate
4XX:
description: Default Response
content:
application/json:
schema:
title: Error Response
additionalProperties: true
type: object
properties:
error:
type: string
message:
type: string
required:
- error
servers:
- url: https://api.hiro.so/
description: mainnet
/v2/fees/transaction:
post:
summary: Get approximate fees for the given transaction
tags:
- Fees
security: []
description: 'Get an estimated fee for the supplied transaction. This
estimates the execution cost of the transaction, the current
fee rate of the network, and returns estimates for fee
amounts.
* `transaction_payload` is a hex-encoded serialization of
the TransactionPayload for the transaction.
* `estimated_len` is an optional argument that provides the
endpoint with an estimation of the final length (in bytes)
of the transaction, including any post-conditions and
signatures
If the node cannot provide an estimate for the transaction
(e.g., if the node has never seen a contract-call for the
given contract and function) or if estimation is not
configured on this node, a 400 response is returned.
The 400 response will be a JSON error containing a `reason`
field which can be one of the following:
* `DatabaseError` - this Stacks node has had an internal
database error while trying to estimate the costs of the
supplied transaction.
* `NoEstimateAvailable` - this Stacks node has not seen this
kind of contract-call before, and it cannot provide an
estimate yet.
* `CostEstimationDisabled` - this Stacks node does not perform
fee or cost estimation, and it cannot respond on this
endpoint.
The 200 response contains the following data:
* `estimated_cost` - the estimated multi-dimensional cost of
executing the Clarity VM on the provided transaction.
* `estimated_cost_scalar` - a unitless integer that the Stacks
node uses to compare how much of the block limit is consumed
by different transactions. This value incorporates the
estimated length of the transaction and the estimated
execution cost of the transaction. The range of this integer
may vary between different Stacks nodes. In order to compute
an estimate of total fee amount for the transaction, this
value is multiplied by the same Stacks node"s estimated fee
rate.
* `cost_scalar_change_by_byte` - a float value that indicates how
much the `estimated_cost_scalar` value would increase for every
additional byte in the final transaction.
* `estimations` - an array of estimated fee rates and total fees to
pay in microSTX for the transaction. This array provides a range of
estimates (default: 3) that may be used. Each element of the array
contains the following fields:
* `fee_rate` - the estimated value for the current fee
rates in the network
* `fee` - the estimated value for the total fee in
microSTX that the given transaction should pay. These
values are the result of computing:
`fee_rate` x `estimated_cost_scalar`.
If the estimated fees are less than the minimum relay
fee `(1 ustx x estimated_len)`, then that minimum relay
fee will be returned here instead.
Note: If the final transaction"s byte size is larger than
supplied to `estimated_len`, then applications should increase
this fee amount by:
`fee_rate` x `cost_scalar_change_by_byte` x (`final_size` - `estimated_size`)'
operationId: getFeeTransaction
requestBody:
content:
application/json:
schema:
$ref: '#/components/schemas/FeeTransactionRequest'
examples:
fee-transaction-request:
summary: Fee estimation request
value:
estimated_len: 350
transaction_payload: 021af942874ce525e87f21bbe8c121b12fac831d02f4086765742d696e666f0b7570646174652d696e666f00000000
responses:
'200':
description: Estimated fees for the transaction
content:
application/json:
schema:
$ref: '#/components/schemas/FeeTransactionResponse'
examples:
fee-transaction-response:
$ref: ./components/examples/fee-transaction-response.example.json
'400':
description: Fee estimation error
content:
application/json:
schema:
$ref: '#/components/schemas/FeeTransactionError'
text/plain:
schema:
type: string
example: 'Failed to decode: Failed to parse JSON body'
'500':
$ref: '#/components/responses/InternalServerError'
servers:
- url: http://localhost:20443
description: Local Stacks Node
/v2/fees/transfer:
get:
summary: Get estimated fee
tags:
- Fees
security: []
operationId: getFeeTransfer
description: 'Get an estimated fee rate for STX transfer transactions. This is a fee
rate per byte, returned as a JSON integer (microSTX per byte).'
responses:
'200':
description: Fee rate in microSTX per byte
content:
application/json:
schema:
type: integer
minimum: 1
description: Fee rate in microSTX per byte
example: 3
'500':
$ref: '#/components/responses/InternalServerError'
servers:
- url: http://localhost:20443
description: Local Stacks Node
components:
schemas:
FeeTransactionRequest:
$ref: ./components/schemas/fee-transaction-request.schema.yaml
FeeTransactionError:
$ref: ./components/schemas/fee-transaction-error.schema.yaml
FeeTransactionResponse:
$ref: ./components/schemas/fee-transaction-response.schema.yaml
responses:
InternalServerError:
description: Internal Server Error
content:
text/plain:
schema:
type: string
example: Internal Server Error
securitySchemes:
rpcAuth:
type: apiKey
in: header
name: authorization
description: 'Plain-text secret value that must exactly equal the node''s
configured password, which is set as `connection_options.auth_token`
in the node''s configuration file.
'
externalDocs:
url: https://github.com/hirosystems/stacks-blockchain-api
description: Source Repository
x-refined-from:
- hiro-stacks-blockchain-api-openapi.yaml
- hiro-stacks-node-rpc-api-openapi.yaml