ExchangeRebel Fee Oracle API
The Fee Oracle API from ExchangeRebel — 6 operation(s) for fee oracle.
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OpenAPI Specification
openapi: 3.2.0
info:
title: ExchangeRebel — pay-per-call APIs for AI agents (x402 on…
version: 1.0.0
contact:
name: 'ExchangeRebel (operator: Rebel Data)'
url: https://exchangerebel.com
email: sound.money.investing@gmail.com
x-guidance: 'All paid operations use x402 on Solana: call without payment to get a 402 challenge (SOL recipient + USDC token account + fresh memo), pay with the memo attached via the Solana Memo program, then retry with header X-Payment-Tx: <signature> and ?toll_memo=<memo>. Challenges are dual-version: the PAYMENT-REQUIRED header carries the x402 v2 PaymentRequired object and the response body carries the same challenge in x402 v1 form for compatibility. Free operations (security: []) include each service''s /health catalog with full response shapes. Prices in x-payment-info are USD per call unless the summary says otherwise (RPC is per 1,000-request block; Telegram provisioning is per bot-month; transcription is per minute of audio).'
description: '67 data and utility APIs behind x402 tolls, settled in SOL or USDC on Solana. Call a paid endpoint without payment to receive a 402 x402 challenge (recipient + fresh memo), pay with the memo attached via the Solana Memo program, then retry with the X-Payment-Tx header and toll_memo query parameter. Free catalog/health endpoints are marked without x-payment-info. Full catalogs: GET /toll/discovery and each service''s /health.'
servers:
- url: https://exchangerebel.com
tags:
- name: Fee Oracle
paths:
/toll/fees/estimate:
post:
tags:
- Fee Oracle
summary: Estimate a Solana transaction's total fee cost
responses:
'200':
description: Success. Response shape is documented in the service catalog (GET /health on the service).
content:
application/json:
example:
priority: medium
percentile_used: p75
micro_lamports: 9000
compute_units: 540
cu_estimated: true
compute_units_consumed: 450
base_fee_lamports: 5000
priority_fee_lamports: 5
total_fee_lamports: 5005
confidence: high
sample_size: 3
breakdown:
consumed_cu: 450
recommended_cu_limit: 540
buffer: +20%
micro_lamports_per_cu: 9000
percentile: p75
inputs_summary:
sources:
- solana-rpc:simulateTransaction
- solana-rpc:getRecentPrioritizationFees
sample_size: 3
envelope:
v: 1
service: fee-oracle
source: solana-rpc
grade: derived
max_age_seconds: 10
changes:
supported: false
'402':
description: 'Payment Required (x402). The PAYMENT-REQUIRED response header carries the x402 v2 PaymentRequired object (base64 JSON: scheme, CAIP-2 network, amount, asset, payTo, plus the bazaar discovery extension); the response body carries the same challenge in x402 v1 form for compatibility, naming the SOL recipient and USDC token account on Solana plus a fresh memo. To pay on this service''s rail: pay with the memo attached (Solana Memo program), then retry with header ''X-Payment-Tx: <transaction signature>'' and query parameter ''toll_memo=<memo>''.'
requestBody:
content:
application/json:
schema:
type: object
properties:
transaction_base64:
type: string
description: string (or use accounts)
accounts:
type: array
description: array of pubkeys
items:
type: string
priority:
type: string
description: low|medium|high
x-payment-info:
protocols:
- x402
price:
mode: fixed
currency: USD
amount: '0.005'
security:
- x402Payment: []
operationId: postTollFeesEstimate
x-operation-id-source: derived
/toll/fees/optimize:
post:
tags:
- Fee Oracle
summary: Return an unsigned, fee-optimized version of a transaction
responses:
'200':
description: Success. Response shape is documented in the service catalog (GET /health on the service).
content:
application/json:
example:
optimized_transaction_base64: AAEAAgQHBwcHBwcHBwcHBwcHBwcHBwcHBwcHBwcHBwcHBwcHBwkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAADBkZv5SEXMv/srbpyw5vnvIzlu8X3EmssQ5s6QAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAwMABQIcAgAAAwAJAygjAAAAAAAAAgIAAQwCAAAAQEIPAAAAAAA=
unsigned: true
signing_note: This transaction is UNSIGNED (signature count = 0). Sign it with your keypair before submitting. We never touch private keys.
compute_units_consumed: 450
compute_units_recommended: 540
micro_lamports: 9000
priority: medium
original_fee_lamports: 17600
optimized_fee_lamports: 5005
savings_pct: 71.56
saved_lamports: 12595
confidence: high
baseline:
cu_limit: 1400000
micro_lamports: 9000
had_compute_budget_ix: false
inputs_summary:
sources:
- solana-rpc:simulateTransaction
- solana-rpc:getRecentPrioritizationFees
sample_size: 3
envelope:
v: 1
service: fee-oracle
source: solana-rpc
grade: derived
max_age_seconds: 10
changes:
supported: false
'402':
description: 'Payment Required (x402). The PAYMENT-REQUIRED response header carries the x402 v2 PaymentRequired object (base64 JSON: scheme, CAIP-2 network, amount, asset, payTo, plus the bazaar discovery extension); the response body carries the same challenge in x402 v1 form for compatibility, naming the SOL recipient and USDC token account on Solana plus a fresh memo. To pay on this service''s rail: pay with the memo attached (Solana Memo program), then retry with header ''X-Payment-Tx: <transaction signature>'' and query parameter ''toll_memo=<memo>''.'
requestBody:
content:
application/json:
schema:
type: object
properties:
transaction_base64:
type: string
description: string
priority:
type: string
description: low|medium|high
x-payment-info:
protocols:
- x402
price:
mode: fixed
currency: USD
amount: '0.005'
security:
- x402Payment: []
operationId: postTollFeesOptimize
x-operation-id-source: derived
/toll/fees/fees:
get:
tags:
- Fee Oracle
summary: Current network fee percentiles (free)
responses:
'200':
description: Success. Response shape is documented in the service catalog (GET /health on the service).
security: []
operationId: getTollFeesFees
x-operation-id-source: derived
/toll/fees/health:
get:
tags:
- Fee Oracle
summary: Upstream RPC status, latency, toll schedule
responses:
'200':
description: Success. Response shape is documented in the service catalog (GET /health on the service).
security: []
operationId: getTollFeesHealth
x-operation-id-source: derived
/toll/fees/recipe:
post:
tags:
- Fee Oracle
summary: Fuse fee estimate + optimize into one recipe
responses:
'200':
description: Success. Response shape is documented in the service catalog (GET /health on the service).
content:
application/json:
example:
cap: null
cap_exceeded: false
confidence: high
cu_limit: 540
escalation_ladder:
ceiling: null
rungs:
- after_seconds: 0
lamports: 5
micro_lamports: 9000
percentile: p75
- after_seconds: 30
lamports: 5
micro_lamports: 9000
percentile: p95
- after_seconds: 90
lamports: 5
micro_lamports: 9000
percentile: p99
expected_total_fee:
lamports: 5005
sol: 5.005e-06
fee_tiers:
- chosen: false
micro_lamports: 5000
percentile: p50
priority_fee_lamports: 3
total_fee_lamports: 5003
urgency: economy
- chosen: true
micro_lamports: 9000
percentile: p75
priority_fee_lamports: 5
total_fee_lamports: 5005
urgency: balanced
- chosen: false
micro_lamports: 9000
percentile: p95
priority_fee_lamports: 5
total_fee_lamports: 5005
urgency: fast
rewritten_tx: AA...
urgency: balanced
'402':
description: 'Payment Required (x402). The PAYMENT-REQUIRED response header carries the x402 v2 PaymentRequired object (base64 JSON: scheme, CAIP-2 network, amount, asset, payTo, plus the bazaar discovery extension); the response body carries the same challenge in x402 v1 form for compatibility, naming the SOL recipient and USDC token account on Solana plus a fresh memo. To pay on this service''s rail: pay with the memo attached (Solana Memo program), then retry with header ''X-Payment-Tx: <transaction signature>'' and query parameter ''toll_memo=<memo>''.'
requestBody:
content:
application/json:
schema:
type: object
properties:
fee_cap_lamports:
type: integer
description: integer - Optional max total fee in lamports. If the chosen tier's expected total fee exceeds it, the answer carries cap_exceeded:true and rewritten_tx:null — never an over-cap transaction.
transaction_base64:
type: string
description: string (required) - Unsigned Solana transaction, base64 (same field as /estimate and /optimize). Required.
urgency:
type: string
description: string - economy=p50, balanced=p75, fast=p95 priority-fee percentile; selects the tier baked into rewritten_tx.
required:
- transaction_base64
x-payment-info:
protocols:
- x402
price:
mode: fixed
currency: USD
amount: '0.01'
security:
- x402Payment: []
operationId: postTollFeesRecipe
x-operation-id-source: derived
/toll/fees/recipe/preflight:
post:
tags:
- Fee Oracle
summary: 'Free pre-check twin: exact $0.01 price first'
responses:
'200':
description: Success. Response shape is documented in the service catalog (GET /health on the service).
requestBody:
content:
application/json:
schema:
type: object
properties:
fee_cap_lamports:
type: integer
description: integer - Optional max total fee in lamports. If the chosen tier's expected total fee exceeds it, the answer carries cap_exceeded:true and rewritten_tx:null — never an over-cap transaction.
transaction_base64:
type: string
description: string (required) - Unsigned Solana transaction, base64 (same field as /estimate and /optimize). Required.
urgency:
type: string
description: string - economy=p50, balanced=p75, fast=p95 priority-fee percentile; selects the tier baked into rewritten_tx.
required:
- transaction_base64
security: []
operationId: postTollFeesRecipePreflight
x-operation-id-source: derived
components:
securitySchemes:
x402Payment:
type: apiKey
in: header
name: X-Payment-Tx
description: 'x402 toll payment proof: the Solana transaction signature of a payment carrying the memo from the 402 challenge; send together with ?toll_memo=<memo>. Payment itself is made on-chain in SOL or USDC to the recipient named in the challenge.'