flexyield-io Rpc API
The Rpc API from flexyield-io — 1 operation(s) for rpc.
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OpenAPI Specification
openapi: 3.2.0
info:
title: FlexYield Rpc API
version: 1.0.0
description: 'One API key, one bill, every provider. JSON-RPC relay across 6 chains, the toolbox, the data API and account statements. Weighted metering (standard 1 · heavy 2 · data 10 · toolbox 1 · cache hit 0); every error carries data.request_id and data.support. Agents: the same capabilities are MCP tools at https://flexyield.io/mcp.'
contact:
email: hello@flexyield.io
url: https://flexyield.io/support
termsOfService: https://flexyield.io/terms
servers:
- url: https://flexyield.io
tags:
- name: RPC
paths:
/rpc/{chain}:
post:
summary: JSON-RPC relay with multi-provider failover
security:
- bearer: []
- x402: []
parameters:
- name: chain
in: path
required: true
schema:
type: string
enum:
- eth_mainnet
- base_mainnet
- arbitrum_one
- optimism_mainnet
- polygon_pos
- solana_mainnet
requestBody:
required: true
content:
application/json:
schema:
$ref: '#/components/schemas/JsonRpcRequest'
responses:
'200':
description: The upstream's JSON-RPC response (also for in-band JSON-RPC errors)
content:
application/json:
schema:
$ref: '#/components/schemas/JsonRpcResponse'
'402':
description: 'x402 lane: the settlement is unknown, spent or expired — pay against the menu at /x402 and retry with X-PAYMENT'
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
'404':
description: Unknown chain (-32600) or method not in the catalog (-32601, with the concierge doorway)
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
'401':
description: Invalid or missing API key (-32001)
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
'429':
description: Rate window, key budget, plan quota or service cap reached (-32005/-32006/-32007/-32014) — the body says what to do next
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
'403':
description: Service switched off for this account/key (-32012) or account suspended (-32009)
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
x-payment-info:
x402Version: 1
scheme: exact
network: base
asset: USDC
mainnetLive: true
menu: https://flexyield.io/x402
redeem: https://flexyield.io/x402/redeem
header: X-PAYMENT
redeemBody:
tx_hash: <settlement tx hash>
tier: cheap | balanced | fast
signature: EIP-191 personal_sign by the paying wallet over messageToSign
messageToSign: 'FlexYield x402 redeem
<settlement tx hash>'
credential: one-time token (fyx_…) in the redeem response; the tx hash is not a credential
maxUnitsPerSettlement: 200000
unitsPerPayment: 10000
windowSeconds: 3600
tax: 'Prices are net. VAT is added on top where it applies, by the payer''s location at quote time (IP evidence): 20 % for payers in the EU or not located, none outside the EU. Units follow the net amount paid.'
tiers:
- name: cheap
label: Public-pool supply, best-effort
priceAtomicPer1kUnits: 4500
usdPerMillionUnits: 4.5
netAmountRequired: '45000'
maxAmountRequired: '54000'
- name: balanced
label: Measured wholesale blend, health-scored routing
priceAtomicPer1kUnits: 9000
usdPerMillionUnits: 9.0
netAmountRequired: '90000'
maxAmountRequired: '108000'
- name: fast
label: Premium slice, lowest measured latency
priceAtomicPer1kUnits: 18000
usdPerMillionUnits: 18.0
netAmountRequired: '180000'
maxAmountRequired: '216000'
tags:
- RPC
operationId: postRpcByChain
x-operation-id-source: derived
components:
schemas:
JsonRpcResponse:
type: object
properties:
jsonrpc:
type: string
id: {}
result: {}
error:
type: object
Error:
type: object
properties:
error:
type: object
properties:
code:
type: integer
description: JSON-RPC style code, e.g. -32005 rate window
message:
type: string
data:
type: object
properties:
request_id:
type: string
format: uuid
support:
type: string
description: Path to file this call as a ticket
JsonRpcRequest:
type: object
required:
- jsonrpc
- method
properties:
jsonrpc:
type: string
const: '2.0'
id: {}
method:
type: string
params:
type: array
securitySchemes:
bearer:
type: http
scheme: bearer
description: Your FlexYield API key (fy_…). Free tier at https://flexyield.io/registration/new
x402:
type: apiKey
in: header
name: X-PAYMENT
description: 'x402 lane: the one-time credential (fyx_…) returned by POST https://flexyield.io/x402/redeem after a payment against the menu at https://flexyield.io/x402 (base); the redeem needs an EIP-191 signature by the paying wallet — the tx hash alone is public and is not a credential'
externalDocs:
url: https://flexyield.io/docs
description: Developer docs
x-pricing:
rule: 'Price per unit falls with commitment, never with identity: more volume committed per month → lower USD per 1M units; yearly < monthly; per call is the dearest lane; no pack undercuts the yearly tier; a subscription is cheapest per unit at its included volume.'
unit: USD per 1,000,000 standard units (standard 1 · heavy 2 · data 10 · cache hit 0), net — VAT is added where it applies on every lane, incl. per call (by the payer's location)
tierMultipliers:
cheap: 0.5
balanced: 1.0
fast: 2.0
lanes:
- key: scale_yearly
label: Scale (yearly)
kind: subscription
commitmentUsd: 2990.0
priceUsd: 249.17
units: 60000000
usdPerMillionUnits: 4.15
supply: premium
fastShare: 0.25
live: true
- key: growth_yearly
label: Growth (yearly)
kind: subscription
commitmentUsd: 8990.0
priceUsd: 749.17
units: 200000000
usdPerMillionUnits: 3.75
supply: premium
fastShare: 0.2
live: true
- key: pro_yearly
label: Pro (yearly)
kind: subscription
commitmentUsd: 990.0
priceUsd: 82.5
units: 15000000
usdPerMillionUnits: 5.5
supply: premium
fastShare: 0.3
live: true
- key: scale_monthly
label: Scale
kind: subscription
commitmentUsd: 299.0
priceUsd: 299.0
units: 60000000
usdPerMillionUnits: 4.98
supply: premium
fastShare: 0.25
live: true
- key: growth_monthly
label: Growth
kind: subscription
commitmentUsd: 899.0
priceUsd: 899.0
units: 200000000
usdPerMillionUnits: 4.5
supply: premium
fastShare: 0.2
live: true
- key: pack_l
label: Pack L
kind: pack
commitmentUsd: 200.0
priceUsd: 200.0
units: 32000000
usdPerMillionUnits: 6.25
supply: premium
fastShare: 0.0
live: true
- key: pro_monthly
label: Pro
kind: subscription
commitmentUsd: 99.0
priceUsd: 99.0
units: 15000000
usdPerMillionUnits: 6.6
supply: premium
fastShare: 0.3
live: true
- key: pack_m
label: Pack M
kind: pack
commitmentUsd: 50.0
priceUsd: 50.0
units: 7000000
usdPerMillionUnits: 7.14
supply: premium
fastShare: 0.0
live: true
- key: pack_s
label: Pack S
kind: pack
commitmentUsd: 10.0
priceUsd: 10.0
units: 1200000
usdPerMillionUnits: 8.33
supply: premium
fastShare: 0.0
live: true
- key: per_call
label: Per call (x402) / PAYG
kind: per_call
commitmentUsd: 0.0
priceUsd: 9.0
units: 1000000
usdPerMillionUnits: 9.0
supply: premium
fastShare: 1.0
live: true
- key: builder
label: Builder
kind: flat
commitmentUsd: 12.0
priceUsd: 12.0
units: 20000000
usdPerMillionUnits: 0.6
supply: public
fastShare: 0.0
live: true
- key: free
label: Free
kind: free
commitmentUsd: 0.0
priceUsd: 0.0
units: 1000000
usdPerMillionUnits: 0.0
supply: public
fastShare: 0.0
live: true
- key: door1
label: Anonymous key (door 1)
kind: free
commitmentUsd: 0.0
priceUsd: 0.0
units: 300000
usdPerMillionUnits: 0.0
supply: public
fastShare: 0.0
live: false
- key: founding
label: Founding (Pro locked 12 months; until 2026-12-05 or while seats last)
kind: subscription
commitmentUsd: 79.0
priceUsd: 79.0
units: 15000000
usdPerMillionUnits: 5.27
supply: premium
fastShare: 0.3
live: true