SingIt Ask
payment-ready until 2026-11-11
OpenAI-compatible pay-per-answer chat across 100+ models (Claude, GPT, Gemini, Grok, DeepSeek, Qwen), plus image, speech and Exa search routes.
Compare: all LLM APIs
Call it x402 v2
x402 v2
- Base URL
- https://ask.singitai.app
- Payment
- x402 v2, header channel
$ curl -i -X POST 'https://ask.singitai.app/v1/chat/claude-haiku-5.5' An unpaid request returns HTTP 402 with the payment terms. Sign a payment authorization, then retry with the PAYMENT-SIGNATURE header.
Endpoints 7 paid routes on ask.singitai.app
POST/v1/chat/claude-haiku-5.5 Base+Sol $0.0015since 11-04
POST/v1/chat/claude-opus-5.5 Base+Sol $0.006856since 11-04
POST/v1/chat/completions Base+Sol $0.0015since 11-04
POST/v1/chat/gpt-5.5 Base+Sol $0.009736since 11-04
POST/v1/exa/answer Base+Sol $0.006since 11-04
POST/v1/exa/contents Base+Sol $0.002since 11-04
POST/v1/exa/search Base+Sol $0.008since 11-04
Prices as captured in the 402 response: median $0.006 across the 7 endpoints, unchanged since first capture.
Example 402 response
Endpoints and prices
| Method | Path | Description | Price | Network | Asset | 402 channel | Captured |
|---|---|---|---|---|---|---|---|
| POST | / | Chat completions API for Claude Haiku 5.5 (Anthropic), OpenAI-compatible. Pay per call in USDC on Base or Solana, no key; you sign a price cap. | $0.0015 | Base+ | USDC | header | since 11-04 |
| POST | / | Chat completions API for Claude Opus 5.5 (Anthropic), OpenAI-compatible. Pay per call in USDC on Base or Solana, no key; you sign a price cap. | $0.006856 | Base+ | USDC | header | since 11-04 |
| POST | / | OpenAI-compatible chat API: 200+ models, or singit/auto to pick by tier. Pay per call in USDC on Base or Solana; free/ models need no payment. | $0.0015 | Base+ | USDC | header | since 11-04 |
| POST | / | Chat completions API for GPT-5.5 (OpenAI), OpenAI-compatible. Pay per call in USDC on Base or Solana, no key; you sign a price cap. | $0.009736 | Base+ | USDC | header | since 11-04 |
| POST | / | Cited web answer API (Exa): a sourced answer, not raw results. Pay per call in USDC on Base or Solana, no key. Exa list price plus $0.001. | $0.006 | Base+ | USDC | header | since 11-04 |
| POST | / | Page contents API (Exa): text, highlights or a summary from up to 10 URLs. Pay per call in USDC on Base or Solana, no key. Exa list price plus $0.001. | $0.002 | Base+ | USDC | header | since 11-04 |
| POST | / | Web search API (Exa): up to 25 ranked results, optional page contents. Pay per call in USDC on Base or Solana, no key. Exa list price plus $0.001. | $0.008 | Base+ | USDC | header | since 11-04 |
Payment evidence
402 payload captured at . Check evidence JSON · Measurement methodology.
First of 7 payloads captured by the monitor.
468 lines, scroll inside
{
"error": "Payment required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"billing": {
"mode": "actual_usage",
"version": 1,
"markupBps": 3000,
"maxChargeAtomic": "1500",
"settlementFeeAtomic": "1000"
},
"version": "2",
"facilitatorAddress": "0x2A89407a98A0732b7fD578c4E156B7166540EB5A",
"assetTransferMethod": "permit2"
},
"payTo": "0xC23d1Dc0f5fCe1abfFB051e06cB93f0329968B4e",
"amount": "1500",
"scheme": "upto",
"network": "eip155:8453",
"maxTimeoutSeconds": 120
},
{
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"extra": {
"billing": {
"mode": "actual_usage",
"version": 1,
"markupBps": 3000,
"maxChargeAtomic": "2429",
"settlementFeeAtomic": "2000"
},
"feePayer": "Hc3sdEAsCGQcpgfivywog9uwtk8gUBUZgsxdME1EJy88",
"paymentFlow": "escrow",
"tokenProgram": "TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA",
"withdrawDelay": 300,
"receiverAuthorizer": "9dpHxn3XFZMZv59vE5MKxhfwGUCCgkcCUzYZLpdEm7ox",
"transactionVersions": [
0
]
},
"payTo": "4an2sqamWWhny9mjLsMtGXCDXakeNtg6vSLq4QvhdmQu",
"amount": "2429",
"scheme": "upto",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 300
},
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"billing": {
"mode": "exact_ceiling",
"version": 1,
"markupBps": 3000,
"maxChargeAtomic": "1500",
"settlementFeeAtomic": "1000"
},
"version": "2"
},
"payTo": "0xC23d1Dc0f5fCe1abfFB051e06cB93f0329968B4e",
"amount": "1500",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 120
},
{
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"extra": {
"billing": {
"mode": "exact_ceiling",
"version": 1,
"markupBps": 3000,
"maxChargeAtomic": "2145",
"settlementFeeAtomic": "2000"
},
"feePayer": "D6ZhtNQ5nT9ZnTHUbqXZsTx5MH2rPFiBBggX4hY1WePM"
},
"payTo": "4an2sqamWWhny9mjLsMtGXCDXakeNtg6vSLq4QvhdmQu",
"amount": "2145",
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 300
}
],
"resource": {
"url": "https://ask.singitai.app/v1/chat/completions",
"tags": [
"llm",
"chat-completions",
"inference",
"openai-compatible",
"chat",
"claude",
"gpt",
"gemini",
"deepseek",
"singit"
],
"iconUrl": "https://singitai.app/assets/icons/icon-512.png",
"mimeType": "application/json",
"description": "OpenAI-compatible chat API: 200+ models, or singit/auto to pick by tier. Pay per call in USDC on Base or Solana; free/ models need no payment.",
"serviceName": "SingIt LLM Chat Completions"
},
"extensions": {
"bazaar": {
"info": {
"input": {
"body": {
"messages": [
{
"role": "user",
"content": "Where is good coffee near the Colosseum?"
}
],
"max_tokens": 400
},
"type": "http",
"method": "POST",
"bodyType": "json"
},
"output": {
"type": "json",
"example": {
"id": "singit-ask-1791932400000",
"model": "singit-ask",
"usage": {
"total_tokens": 45,
"prompt_tokens": 14,
"buyer_cost_micro": 6,
"completion_tokens": 31
},
"object": "chat.completion",
"billing": {
"mode": "actual_usage",
"version": 1,
"currency": "USDC",
"markupBps": 3000,
"totalAtomic": "1008",
"markupAtomic": "2",
"maxChargeAtomic": "3000",
"providerCostAtomic": "6",
"settlementFeeAtomic": "1000"
},
"choices": [
{
"index": 0,
"message": {
"role": "assistant",
"content": "Around the Colosseum, try Caffè Propaganda on Via Claudia or Bar Martini for an espresso with a view."
},
"finish_reason": "stop"
}
],
"created": 1791932400
}
}
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"input"
],
"properties": {
"input": {
"type": "object",
"required": [
"type",
"method",
"bodyType",
"body"
],
"properties": {
"body": {
"required": [
"messages"
],
"properties": {
"model": {
"type": "string",
"examples": [
"deepseek-v4.1-flash",
"claude-opus-5.5",
"gpt-5.5",
"gemini-3.8-flash"
],
"description": "Any model id from GET /v1/models; the ceiling follows its price. Omit for the default model. Free to try, no payment: free/openai-gpt-oss-20b, free/gemma-4-e2b, free/gemma-3-27b-it, free/mistral-small-3.2-24b-instruct, free/qwen3-coder-30b-a3b-instruct, free/deepseek-v4.1-flash."
},
"stream": {
"enum": [
false
],
"type": "boolean",
"description": "Streaming is not offered."
},
"messages": {
"type": "array",
"items": {
"type": "object",
"required": [
"role",
"content"
],
"properties": {
"role": {
"enum": [
"system",
"user",
"assistant"
],
"type": "string"
},
"content": {
"type": "string",
"description": "Plain text; all messages together under 24000 characters."
}
}
},
"maxItems": 40,
"minItems": 1,
"description": "The conversation, oldest first."
},
"max_tokens": {
"type": "integer",
"default": 800,
"maximum": 1200,
"minimum": 1,
"description": "The longest answer, in tokens; above 1200 counts as 1200. The payment ceiling grows with it; the charge follows what was used."
},
"fallback_models": {
"type": "array",
"items": {
"type": "string"
},
"maxItems": 3,
"minItems": 1,
"description": "Optional on paid /v1/chat/completions only: 1–3 trimmed unique model ids, excluding the pinned model and singit/auto. Before payment, an unavailable pinned model may use the first healthy priced candidate whose Base upto ceiling is no higher than the pinned ceiling, and in the same auto tier if the pinned model has one. The chosen model determines the quote and usage charge.",
"uniqueItems": true
}
},
"description": "Listed price = ceiling for the example (max_tokens 400, list price); a larger max_tokens or longer prompt is quoted higher (max_tokens above 1200 counts as 1200); upto settles actual usage."
},
"type": {
"type": "string",
"const": "http"
},
"method": {
"enum": [
"POST"
],
"type": "string"
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
}
},
"additionalProperties": false
},
"output": {
"type": "object",
"required": [
"type"
],
"properties": {
"type": {
"type": "string"
},
"example": {
"type": "object",
"required": [
"choices",
"billing"
],
"properties": {
"id": {
"type": "string"
},
"model": {
"type": "string"
},
"usage": {
"type": "object",
"description": "Token counts and the model's own cost in micro-USD (buyer_cost_micro)"
},
"object": {
"type": "string",
"const": "chat.completion"
},
"billing": {
"type": "object",
"properties": {
"free": {
"type": "boolean",
"const": true,
"description": "Present for free answers"
},
"hint": {
"type": "string",
"const": "drop the free/ prefix to pay",
"description": "How to request a paid answer"
},
"currency": {
"type": "string",
"const": "USDC"
},
"resetsAt": {
"type": "string",
"description": "Next UTC midnight (ISO 8601) for the free answer allowance"
},
"totalAtomic": {
"type": "string",
"description": "The amount settled"
},
"markupAtomic": {
"type": "string"
},
"remainingToday": {
"type": "integer",
"minimum": 0,
"description": "Free answers left today for this network, limited by the network and whole-day answer counts; the shared cost budget may end free answers sooner"
},
"providerCostAtomic": {
"type": "string"
}
},
"description": "What was charged, in USDC micro-units, or the free answer allowance"
},
"choices": {
"type": "array",
"items": {
"type": "object",
"properties": {
"index": {
"type": "integer"
},
"message": {
"type": "object",
"properties": {
"role": {
"type": "string"
},
"content": {
"type": "string"
}
}
},
"finish_reason": {
"type": "string",
"description": "stop, or length when max_tokens ended the answer"
}
}
}
},
"created": {
"type": "integer",
"description": "Unix seconds"
}
}
}
}
}
}
}
},
"builder-code": {
"info": {
"a": "bc_is3fuv36"
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"a": {
"type": "string",
"pattern": "^[a-z0-9_]{1,32}$",
"description": "App builder code"
},
"s": {
"type": "array",
"items": {
"type": "string",
"pattern": "^[a-z0-9_]{1,32}$"
},
"maxItems": 11,
"description": "Service builder codes"
},
"w": {
"type": "string",
"pattern": "^[a-z0-9_]{1,32}$",
"description": "Wallet builder code"
}
},
"additionalProperties": false
}
},
"eip2612GasSponsoring": {
"info": {
"version": "1",
"description": "The facilitator accepts EIP-2612 gasless Permit to `Permit2` canonical contract."
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"from",
"asset",
"spender",
"amount",
"nonce",
"deadline",
"signature",
"version"
],
"properties": {
"from": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]{40}$",
"description": "The address of the sender."
},
"asset": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]{40}$",
"description": "The address of the ERC-20 token contract."
},
"nonce": {
"type": "string",
"pattern": "^[0-9]+$",
"description": "The current nonce of the sender."
},
"amount": {
"type": "string",
"pattern": "^[0-9]+$",
"description": "The amount to approve (uint256). Typically MaxUint."
},
"spender": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]{40}$",
"description": "The address of the spender (Canonical Permit2)."
},
"version": {
"type": "string",
"pattern": "^[0-9]+(\\.[0-9]+)*$",
"description": "Schema version identifier."
},
"deadline": {
"type": "string",
"pattern": "^[0-9]+$",
"description": "The timestamp at which the signature expires."
},
"signature": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]+$",
"description": "The 65-byte concatenated signature (r, s, v) as a hex string."
}
}
}
}
},
"x402Version": 2
} Other captured 402 responses (6)
Captured payload 2 of 7
{
"error": "Payment required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"billing": {
"mode": "actual_usage",
"version": 1,
"markupBps": 3000,
"maxChargeAtomic": "18524",
"settlementFeeAtomic": "1000"
},
"version": "2",
"facilitatorAddress": "0x42dd53906B49c202E8E934b059dc019E04634b00",
"assetTransferMethod": "permit2"
},
"payTo": "0xC23d1Dc0f5fCe1abfFB051e06cB93f0329968B4e",
"amount": "18524",
"scheme": "upto",
"network": "eip155:8453",
"maxTimeoutSeconds": 120
},
{
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"extra": {
"billing": {
"mode": "actual_usage",
"version": 1,
"markupBps": 3000,
"maxChargeAtomic": "19524",
"settlementFeeAtomic": "2000"
},
"feePayer": "BENrLoUbndxoNMUS5JXApGMtNykLjFXXixMtpDwDR9SP",
"paymentFlow": "escrow",
"tokenProgram": "TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA",
"withdrawDelay": 300,
"receiverAuthorizer": "9dpHxn3XFZMZv59vE5MKxhfwGUCCgkcCUzYZLpdEm7ox",
"transactionVersions": [
0
]
},
"payTo": "4an2sqamWWhny9mjLsMtGXCDXakeNtg6vSLq4QvhdmQu",
"amount": "19524",
"scheme": "upto",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 300
},
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"billing": {
"mode": "exact_ceiling",
"version": 1,
"markupBps": 3000,
"maxChargeAtomic": "6856",
"settlementFeeAtomic": "1000"
},
"version": "2"
},
"payTo": "0xC23d1Dc0f5fCe1abfFB051e06cB93f0329968B4e",
"amount": "6856",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 120
},
{
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"extra": {
"billing": {
"mode": "exact_ceiling",
"version": 1,
"markupBps": 3000,
"maxChargeAtomic": "7856",
"settlementFeeAtomic": "2000"
},
"feePayer": "BENrLoUbndxoNMUS5JXApGMtNykLjFXXixMtpDwDR9SP"
},
"payTo": "4an2sqamWWhny9mjLsMtGXCDXakeNtg6vSLq4QvhdmQu",
"amount": "7856",
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 300
}
],
"resource": {
"url": "https://ask.singitai.app/v1/chat/claude-opus-5.5",
"tags": [
"llm",
"chat-completions",
"claude-opus-5.5",
"anthropic",
"openai-compatible",
"claude",
"inference",
"chat",
"singit"
],
"iconUrl": "https://singitai.app/assets/icons/icon-512.png",
"mimeType": "application/json",
"description": "Chat completions API for Claude Opus 5.5 (Anthropic), OpenAI-compatible. Pay per call in USDC on Base or Solana, no key; you sign a price cap.",
"serviceName": "SingIt Claude Opus 5.5 Chat"
},
"extensions": {
"bazaar": {
"info": {
"input": {
"body": {
"model": "claude-opus-5.5",
"messages": [
{
"role": "user",
"content": "Where is good coffee near the Colosseum? Answer in one sentence. (via Claude Opus 5.5)"
}
],
"max_tokens": 400
},
"type": "http",
"method": "POST",
"bodyType": "json"
},
"output": {
"type": "json",
"example": {
"id": "singit-ask-1791932400000",
"model": "singit-ask",
"usage": {
"total_tokens": 45,
"prompt_tokens": 14,
"buyer_cost_micro": 6,
"completion_tokens": 31
},
"object": "chat.completion",
"billing": {
"mode": "actual_usage",
"version": 1,
"currency": "USDC",
"markupBps": 3000,
"totalAtomic": "1008",
"markupAtomic": "2",
"maxChargeAtomic": "3000",
"providerCostAtomic": "6",
"settlementFeeAtomic": "1000"
},
"choices": [
{
"index": 0,
"message": {
"role": "assistant",
"content": "Around the Colosseum, try Caffè Propaganda on Via Claudia or Bar Martini for an espresso with a view."
},
"finish_reason": "stop"
}
],
"created": 1791932400
}
}
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"input"
],
"properties": {
"input": {
"type": "object",
"required": [
"type",
"method",
"bodyType",
"body"
],
"properties": {
"body": {
"required": [
"messages"
],
"properties": {
"model": {
"type": "string",
"examples": [
"deepseek-v4.1-flash",
"claude-opus-5.5",
"gpt-5.5",
"gemini-3.8-flash"
],
"description": "Any model id from GET /v1/models; the ceiling follows its price. Omit for the default model."
},
"stream": {
"enum": [
false
],
"type": "boolean",
"description": "Streaming is not offered."
},
"messages": {
"type": "array",
"items": {
"type": "object",
"required": [
"role",
"content"
],
"properties": {
"role": {
"enum": [
"system",
"user",
"assistant"
],
"type": "string"
},
"content": {
"type": "string",
"description": "Plain text; all messages together under 24000 characters."
}
}
},
"maxItems": 40,
"minItems": 1,
"description": "The conversation, oldest first."
},
"max_tokens": {
"type": "integer",
"default": 800,
"maximum": 1200,
"minimum": 1,
"description": "The longest answer, in tokens; 1200 is the most, and a larger value counts as 1200. The price cap you sign grows with it (the 402 states the exact amount for your request); the charge follows what was used."
}
},
"description": "Listed price = ceiling for the example (max_tokens 400, list price); a larger max_tokens or longer prompt is quoted higher (max_tokens above 1200 counts as 1200); upto settles actual usage."
},
"type": {
"type": "string",
"const": "http"
},
"method": {
"enum": [
"POST"
],
"type": "string"
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
}
},
"additionalProperties": false
},
"output": {
"type": "object",
"required": [
"type"
],
"properties": {
"type": {
"type": "string"
},
"example": {
"type": "object",
"required": [
"choices",
"billing"
],
"properties": {
"id": {
"type": "string"
},
"model": {
"type": "string"
},
"usage": {
"type": "object",
"description": "Token counts and the model's own cost in micro-USD (buyer_cost_micro)"
},
"object": {
"type": "string",
"const": "chat.completion"
},
"billing": {
"type": "object",
"properties": {
"free": {
"type": "boolean",
"const": true,
"description": "Present for free answers"
},
"hint": {
"type": "string",
"const": "drop the free/ prefix to pay",
"description": "How to request a paid answer"
},
"currency": {
"type": "string",
"const": "USDC"
},
"resetsAt": {
"type": "string",
"description": "Next UTC midnight (ISO 8601) for the free answer allowance"
},
"totalAtomic": {
"type": "string",
"description": "The amount settled"
},
"markupAtomic": {
"type": "string"
},
"remainingToday": {
"type": "integer",
"minimum": 0,
"description": "Free answers left today for this network, limited by the network and whole-day answer counts; the shared cost budget may end free answers sooner"
},
"providerCostAtomic": {
"type": "string"
}
},
"description": "What was charged, in USDC micro-units, or the free answer allowance"
},
"choices": {
"type": "array",
"items": {
"type": "object",
"properties": {
"index": {
"type": "integer"
},
"message": {
"type": "object",
"properties": {
"role": {
"type": "string"
},
"content": {
"type": "string"
}
}
},
"finish_reason": {
"type": "string",
"description": "stop, or length when max_tokens ended the answer"
}
}
}
},
"created": {
"type": "integer",
"description": "Unix seconds"
}
}
}
}
}
}
}
},
"builder-code": {
"info": {
"a": "bc_is3fuv36"
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"a": {
"type": "string",
"pattern": "^[a-z0-9_]{1,32}$",
"description": "App builder code"
},
"s": {
"type": "array",
"items": {
"type": "string",
"pattern": "^[a-z0-9_]{1,32}$"
},
"maxItems": 11,
"description": "Service builder codes"
},
"w": {
"type": "string",
"pattern": "^[a-z0-9_]{1,32}$",
"description": "Wallet builder code"
}
},
"additionalProperties": false
}
},
"eip2612GasSponsoring": {
"info": {
"version": "1",
"description": "The facilitator accepts EIP-2612 gasless Permit to `Permit2` canonical contract."
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"from",
"asset",
"spender",
"amount",
"nonce",
"deadline",
"signature",
"version"
],
"properties": {
"from": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]{40}$",
"description": "The address of the sender."
},
"asset": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]{40}$",
"description": "The address of the ERC-20 token contract."
},
"nonce": {
"type": "string",
"pattern": "^[0-9]+$",
"description": "The current nonce of the sender."
},
"amount": {
"type": "string",
"pattern": "^[0-9]+$",
"description": "The amount to approve (uint256). Typically MaxUint."
},
"spender": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]{40}$",
"description": "The address of the spender (Canonical Permit2)."
},
"version": {
"type": "string",
"pattern": "^[0-9]+(\\.[0-9]+)*$",
"description": "Schema version identifier."
},
"deadline": {
"type": "string",
"pattern": "^[0-9]+$",
"description": "The timestamp at which the signature expires."
},
"signature": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]+$",
"description": "The 65-byte concatenated signature (r, s, v) as a hex string."
}
}
}
}
},
"x402Version": 2
}Captured payload 3 of 7
{
"error": "Payment required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"billing": {
"mode": "actual_usage",
"version": 1,
"markupBps": 3000,
"maxChargeAtomic": "27117",
"settlementFeeAtomic": "1000"
},
"version": "2",
"facilitatorAddress": "0x625d8a65134079f8faAAc39a7947c73d93C6aC39",
"assetTransferMethod": "permit2"
},
"payTo": "0xC23d1Dc0f5fCe1abfFB051e06cB93f0329968B4e",
"amount": "27117",
"scheme": "upto",
"network": "eip155:8453",
"maxTimeoutSeconds": 120
},
{
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"extra": {
"billing": {
"mode": "actual_usage",
"version": 1,
"markupBps": 3000,
"maxChargeAtomic": "28117",
"settlementFeeAtomic": "2000"
},
"feePayer": "GVJJ7rdGiXr5xaYbRwRbjfaJL7fmwRygFi1H6aGqDveb",
"paymentFlow": "escrow",
"tokenProgram": "TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA",
"withdrawDelay": 300,
"receiverAuthorizer": "9dpHxn3XFZMZv59vE5MKxhfwGUCCgkcCUzYZLpdEm7ox",
"transactionVersions": [
0
]
},
"payTo": "4an2sqamWWhny9mjLsMtGXCDXakeNtg6vSLq4QvhdmQu",
"amount": "28117",
"scheme": "upto",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 300
},
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"billing": {
"mode": "exact_ceiling",
"version": 1,
"markupBps": 3000,
"maxChargeAtomic": "9736",
"settlementFeeAtomic": "1000"
},
"version": "2"
},
"payTo": "0xC23d1Dc0f5fCe1abfFB051e06cB93f0329968B4e",
"amount": "9736",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 120
},
{
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"extra": {
"billing": {
"mode": "exact_ceiling",
"version": 1,
"markupBps": 3000,
"maxChargeAtomic": "10736",
"settlementFeeAtomic": "2000"
},
"feePayer": "BENrLoUbndxoNMUS5JXApGMtNykLjFXXixMtpDwDR9SP"
},
"payTo": "4an2sqamWWhny9mjLsMtGXCDXakeNtg6vSLq4QvhdmQu",
"amount": "10736",
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 300
}
],
"resource": {
"url": "https://ask.singitai.app/v1/chat/gpt-5.5",
"tags": [
"llm",
"chat-completions",
"gpt-5.5",
"openai",
"openai-compatible",
"gpt",
"inference",
"chat",
"singit"
],
"iconUrl": "https://singitai.app/assets/icons/icon-512.png",
"mimeType": "application/json",
"description": "Chat completions API for GPT-5.5 (OpenAI), OpenAI-compatible. Pay per call in USDC on Base or Solana, no key; you sign a price cap.",
"serviceName": "SingIt GPT-5.5 Chat"
},
"extensions": {
"bazaar": {
"info": {
"input": {
"body": {
"model": "gpt-5.5",
"messages": [
{
"role": "user",
"content": "Where is good coffee near the Colosseum? Answer in one sentence. (via GPT-5.5)"
}
],
"max_tokens": 400
},
"type": "http",
"method": "POST",
"bodyType": "json"
},
"output": {
"type": "json",
"example": {
"id": "singit-ask-1791932400000",
"model": "singit-ask",
"usage": {
"total_tokens": 45,
"prompt_tokens": 14,
"buyer_cost_micro": 6,
"completion_tokens": 31
},
"object": "chat.completion",
"billing": {
"mode": "actual_usage",
"version": 1,
"currency": "USDC",
"markupBps": 3000,
"totalAtomic": "1008",
"markupAtomic": "2",
"maxChargeAtomic": "3000",
"providerCostAtomic": "6",
"settlementFeeAtomic": "1000"
},
"choices": [
{
"index": 0,
"message": {
"role": "assistant",
"content": "Around the Colosseum, try Caffè Propaganda on Via Claudia or Bar Martini for an espresso with a view."
},
"finish_reason": "stop"
}
],
"created": 1791932400
}
}
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"input"
],
"properties": {
"input": {
"type": "object",
"required": [
"type",
"method",
"bodyType",
"body"
],
"properties": {
"body": {
"required": [
"messages"
],
"properties": {
"model": {
"type": "string",
"examples": [
"deepseek-v4.1-flash",
"claude-opus-5.5",
"gpt-5.5",
"gemini-3.8-flash"
],
"description": "Any model id from GET /v1/models; the ceiling follows its price. Omit for the default model."
},
"stream": {
"enum": [
false
],
"type": "boolean",
"description": "Streaming is not offered."
},
"messages": {
"type": "array",
"items": {
"type": "object",
"required": [
"role",
"content"
],
"properties": {
"role": {
"enum": [
"system",
"user",
"assistant"
],
"type": "string"
},
"content": {
"type": "string",
"description": "Plain text; all messages together under 24000 characters."
}
}
},
"maxItems": 40,
"minItems": 1,
"description": "The conversation, oldest first."
},
"max_tokens": {
"type": "integer",
"default": 800,
"maximum": 1200,
"minimum": 1,
"description": "The longest answer, in tokens; 1200 is the most, and a larger value counts as 1200. The price cap you sign grows with it (the 402 states the exact amount for your request); the charge follows what was used."
}
},
"description": "Listed price = ceiling for the example (max_tokens 400, list price); a larger max_tokens or longer prompt is quoted higher (max_tokens above 1200 counts as 1200); upto settles actual usage."
},
"type": {
"type": "string",
"const": "http"
},
"method": {
"enum": [
"POST"
],
"type": "string"
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
}
},
"additionalProperties": false
},
"output": {
"type": "object",
"required": [
"type"
],
"properties": {
"type": {
"type": "string"
},
"example": {
"type": "object",
"required": [
"choices",
"billing"
],
"properties": {
"id": {
"type": "string"
},
"model": {
"type": "string"
},
"usage": {
"type": "object",
"description": "Token counts and the model's own cost in micro-USD (buyer_cost_micro)"
},
"object": {
"type": "string",
"const": "chat.completion"
},
"billing": {
"type": "object",
"properties": {
"free": {
"type": "boolean",
"const": true,
"description": "Present for free answers"
},
"hint": {
"type": "string",
"const": "drop the free/ prefix to pay",
"description": "How to request a paid answer"
},
"currency": {
"type": "string",
"const": "USDC"
},
"resetsAt": {
"type": "string",
"description": "Next UTC midnight (ISO 8601) for the free answer allowance"
},
"totalAtomic": {
"type": "string",
"description": "The amount settled"
},
"markupAtomic": {
"type": "string"
},
"remainingToday": {
"type": "integer",
"minimum": 0,
"description": "Free answers left today for this network, limited by the network and whole-day answer counts; the shared cost budget may end free answers sooner"
},
"providerCostAtomic": {
"type": "string"
}
},
"description": "What was charged, in USDC micro-units, or the free answer allowance"
},
"choices": {
"type": "array",
"items": {
"type": "object",
"properties": {
"index": {
"type": "integer"
},
"message": {
"type": "object",
"properties": {
"role": {
"type": "string"
},
"content": {
"type": "string"
}
}
},
"finish_reason": {
"type": "string",
"description": "stop, or length when max_tokens ended the answer"
}
}
}
},
"created": {
"type": "integer",
"description": "Unix seconds"
}
}
}
}
}
}
}
},
"builder-code": {
"info": {
"a": "bc_is3fuv36"
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"a": {
"type": "string",
"pattern": "^[a-z0-9_]{1,32}$",
"description": "App builder code"
},
"s": {
"type": "array",
"items": {
"type": "string",
"pattern": "^[a-z0-9_]{1,32}$"
},
"maxItems": 11,
"description": "Service builder codes"
},
"w": {
"type": "string",
"pattern": "^[a-z0-9_]{1,32}$",
"description": "Wallet builder code"
}
},
"additionalProperties": false
}
},
"eip2612GasSponsoring": {
"info": {
"version": "1",
"description": "The facilitator accepts EIP-2612 gasless Permit to `Permit2` canonical contract."
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"from",
"asset",
"spender",
"amount",
"nonce",
"deadline",
"signature",
"version"
],
"properties": {
"from": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]{40}$",
"description": "The address of the sender."
},
"asset": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]{40}$",
"description": "The address of the ERC-20 token contract."
},
"nonce": {
"type": "string",
"pattern": "^[0-9]+$",
"description": "The current nonce of the sender."
},
"amount": {
"type": "string",
"pattern": "^[0-9]+$",
"description": "The amount to approve (uint256). Typically MaxUint."
},
"spender": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]{40}$",
"description": "The address of the spender (Canonical Permit2)."
},
"version": {
"type": "string",
"pattern": "^[0-9]+(\\.[0-9]+)*$",
"description": "Schema version identifier."
},
"deadline": {
"type": "string",
"pattern": "^[0-9]+$",
"description": "The timestamp at which the signature expires."
},
"signature": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]+$",
"description": "The 65-byte concatenated signature (r, s, v) as a hex string."
}
}
}
}
},
"x402Version": 2
}Captured payload 4 of 7
{
"error": "Payment required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"billing": {
"mode": "actual_usage",
"version": 1,
"markupBps": 3000,
"maxChargeAtomic": "1500",
"settlementFeeAtomic": "1000"
},
"version": "2",
"facilitatorAddress": "0xCA5e87f82B3FA093800e6ad67D621A427D79c70D",
"assetTransferMethod": "permit2"
},
"payTo": "0xC23d1Dc0f5fCe1abfFB051e06cB93f0329968B4e",
"amount": "1500",
"scheme": "upto",
"network": "eip155:8453",
"maxTimeoutSeconds": 120
},
{
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"extra": {
"billing": {
"mode": "actual_usage",
"version": 1,
"markupBps": 3000,
"maxChargeAtomic": "2440",
"settlementFeeAtomic": "2000"
},
"feePayer": "D6ZhtNQ5nT9ZnTHUbqXZsTx5MH2rPFiBBggX4hY1WePM",
"paymentFlow": "escrow",
"tokenProgram": "TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA",
"withdrawDelay": 300,
"receiverAuthorizer": "9dpHxn3XFZMZv59vE5MKxhfwGUCCgkcCUzYZLpdEm7ox",
"transactionVersions": [
0
]
},
"payTo": "4an2sqamWWhny9mjLsMtGXCDXakeNtg6vSLq4QvhdmQu",
"amount": "2440",
"scheme": "upto",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 300
},
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"billing": {
"mode": "exact_ceiling",
"version": 1,
"markupBps": 3000,
"maxChargeAtomic": "1500",
"settlementFeeAtomic": "1000"
},
"version": "2"
},
"payTo": "0xC23d1Dc0f5fCe1abfFB051e06cB93f0329968B4e",
"amount": "1500",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 120
},
{
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"extra": {
"billing": {
"mode": "exact_ceiling",
"version": 1,
"markupBps": 3000,
"maxChargeAtomic": "2147",
"settlementFeeAtomic": "2000"
},
"feePayer": "Hc3sdEAsCGQcpgfivywog9uwtk8gUBUZgsxdME1EJy88"
},
"payTo": "4an2sqamWWhny9mjLsMtGXCDXakeNtg6vSLq4QvhdmQu",
"amount": "2147",
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 300
}
],
"resource": {
"url": "https://ask.singitai.app/v1/chat/claude-haiku-5.5",
"tags": [
"llm",
"chat-completions",
"claude-haiku-5.5",
"anthropic",
"openai-compatible",
"claude",
"inference",
"chat",
"singit"
],
"iconUrl": "https://singitai.app/assets/icons/icon-512.png",
"mimeType": "application/json",
"description": "Chat completions API for Claude Haiku 5.5 (Anthropic), OpenAI-compatible. Pay per call in USDC on Base or Solana, no key; you sign a price cap.",
"serviceName": "SingIt Claude Haiku 5.5 Chat"
},
"extensions": {
"bazaar": {
"info": {
"input": {
"body": {
"model": "claude-haiku-5.5",
"messages": [
{
"role": "user",
"content": "Where is good coffee near the Colosseum? Answer in one sentence. (via Claude Haiku 5.5)"
}
],
"max_tokens": 400
},
"type": "http",
"method": "POST",
"bodyType": "json"
},
"output": {
"type": "json",
"example": {
"id": "singit-ask-1791932400000",
"model": "singit-ask",
"usage": {
"total_tokens": 45,
"prompt_tokens": 14,
"buyer_cost_micro": 6,
"completion_tokens": 31
},
"object": "chat.completion",
"billing": {
"mode": "actual_usage",
"version": 1,
"currency": "USDC",
"markupBps": 3000,
"totalAtomic": "1008",
"markupAtomic": "2",
"maxChargeAtomic": "3000",
"providerCostAtomic": "6",
"settlementFeeAtomic": "1000"
},
"choices": [
{
"index": 0,
"message": {
"role": "assistant",
"content": "Around the Colosseum, try Caffè Propaganda on Via Claudia or Bar Martini for an espresso with a view."
},
"finish_reason": "stop"
}
],
"created": 1791932400
}
}
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"input"
],
"properties": {
"input": {
"type": "object",
"required": [
"type",
"method",
"bodyType",
"body"
],
"properties": {
"body": {
"required": [
"messages"
],
"properties": {
"model": {
"type": "string",
"examples": [
"deepseek-v4.1-flash",
"claude-opus-5.5",
"gpt-5.5",
"gemini-3.8-flash"
],
"description": "Any model id from GET /v1/models; the ceiling follows its price. Omit for the default model."
},
"stream": {
"enum": [
false
],
"type": "boolean",
"description": "Streaming is not offered."
},
"messages": {
"type": "array",
"items": {
"type": "object",
"required": [
"role",
"content"
],
"properties": {
"role": {
"enum": [
"system",
"user",
"assistant"
],
"type": "string"
},
"content": {
"type": "string",
"description": "Plain text; all messages together under 24000 characters."
}
}
},
"maxItems": 40,
"minItems": 1,
"description": "The conversation, oldest first."
},
"max_tokens": {
"type": "integer",
"default": 800,
"maximum": 1200,
"minimum": 1,
"description": "The longest answer, in tokens; 1200 is the most, and a larger value counts as 1200. The price cap you sign grows with it (the 402 states the exact amount for your request); the charge follows what was used."
}
},
"description": "Listed price = ceiling for the example (max_tokens 400, list price); a larger max_tokens or longer prompt is quoted higher (max_tokens above 1200 counts as 1200); upto settles actual usage."
},
"type": {
"type": "string",
"const": "http"
},
"method": {
"enum": [
"POST"
],
"type": "string"
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
}
},
"additionalProperties": false
},
"output": {
"type": "object",
"required": [
"type"
],
"properties": {
"type": {
"type": "string"
},
"example": {
"type": "object",
"required": [
"choices",
"billing"
],
"properties": {
"id": {
"type": "string"
},
"model": {
"type": "string"
},
"usage": {
"type": "object",
"description": "Token counts and the model's own cost in micro-USD (buyer_cost_micro)"
},
"object": {
"type": "string",
"const": "chat.completion"
},
"billing": {
"type": "object",
"properties": {
"free": {
"type": "boolean",
"const": true,
"description": "Present for free answers"
},
"hint": {
"type": "string",
"const": "drop the free/ prefix to pay",
"description": "How to request a paid answer"
},
"currency": {
"type": "string",
"const": "USDC"
},
"resetsAt": {
"type": "string",
"description": "Next UTC midnight (ISO 8601) for the free answer allowance"
},
"totalAtomic": {
"type": "string",
"description": "The amount settled"
},
"markupAtomic": {
"type": "string"
},
"remainingToday": {
"type": "integer",
"minimum": 0,
"description": "Free answers left today for this network, limited by the network and whole-day answer counts; the shared cost budget may end free answers sooner"
},
"providerCostAtomic": {
"type": "string"
}
},
"description": "What was charged, in USDC micro-units, or the free answer allowance"
},
"choices": {
"type": "array",
"items": {
"type": "object",
"properties": {
"index": {
"type": "integer"
},
"message": {
"type": "object",
"properties": {
"role": {
"type": "string"
},
"content": {
"type": "string"
}
}
},
"finish_reason": {
"type": "string",
"description": "stop, or length when max_tokens ended the answer"
}
}
}
},
"created": {
"type": "integer",
"description": "Unix seconds"
}
}
}
}
}
}
}
},
"builder-code": {
"info": {
"a": "bc_is3fuv36"
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"a": {
"type": "string",
"pattern": "^[a-z0-9_]{1,32}$",
"description": "App builder code"
},
"s": {
"type": "array",
"items": {
"type": "string",
"pattern": "^[a-z0-9_]{1,32}$"
},
"maxItems": 11,
"description": "Service builder codes"
},
"w": {
"type": "string",
"pattern": "^[a-z0-9_]{1,32}$",
"description": "Wallet builder code"
}
},
"additionalProperties": false
}
},
"eip2612GasSponsoring": {
"info": {
"version": "1",
"description": "The facilitator accepts EIP-2612 gasless Permit to `Permit2` canonical contract."
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"from",
"asset",
"spender",
"amount",
"nonce",
"deadline",
"signature",
"version"
],
"properties": {
"from": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]{40}$",
"description": "The address of the sender."
},
"asset": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]{40}$",
"description": "The address of the ERC-20 token contract."
},
"nonce": {
"type": "string",
"pattern": "^[0-9]+$",
"description": "The current nonce of the sender."
},
"amount": {
"type": "string",
"pattern": "^[0-9]+$",
"description": "The amount to approve (uint256). Typically MaxUint."
},
"spender": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]{40}$",
"description": "The address of the spender (Canonical Permit2)."
},
"version": {
"type": "string",
"pattern": "^[0-9]+(\\.[0-9]+)*$",
"description": "Schema version identifier."
},
"deadline": {
"type": "string",
"pattern": "^[0-9]+$",
"description": "The timestamp at which the signature expires."
},
"signature": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]+$",
"description": "The 65-byte concatenated signature (r, s, v) as a hex string."
}
}
}
}
},
"x402Version": 2
}Captured payload 5 of 7
{
"error": "Payment required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0xC23d1Dc0f5fCe1abfFB051e06cB93f0329968B4e",
"amount": "8000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 120
},
{
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"extra": {
"feePayer": "BENrLoUbndxoNMUS5JXApGMtNykLjFXXixMtpDwDR9SP"
},
"payTo": "4an2sqamWWhny9mjLsMtGXCDXakeNtg6vSLq4QvhdmQu",
"amount": "8000",
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 120
}
],
"resource": {
"url": "https://ask.singitai.app/v1/exa/search",
"tags": [
"web-search",
"search",
"exa",
"web-results",
"page-contents",
"pay-per-use",
"solana",
"base",
"singit"
],
"iconUrl": "https://singitai.app/assets/icons/icon-512.png",
"mimeType": "application/json",
"description": "Web search API (Exa): up to 25 ranked results, optional page contents. Pay per call in USDC on Base or Solana, no key. Exa list price plus $0.001.",
"serviceName": "SingIt Web Search (Exa)"
},
"extensions": {
"bazaar": {
"info": {
"input": {
"body": {
"query": "x402 payment facilitators",
"numResults": 5
},
"type": "http",
"method": "POST",
"bodyType": "json"
},
"output": {
"type": "json",
"example": {
"billing": {
"currency": "USDC",
"exaAtomic": "7000",
"feeAtomic": "1000",
"totalAtomic": "8000",
"markupAtomic": "0"
},
"results": [
{
"id": "https://x402.org",
"url": "https://x402.org",
"title": "x402",
"author": null,
"publishedDate": null
}
],
"requestId": "example"
}
}
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"input"
],
"properties": {
"input": {
"type": "object",
"required": [
"type",
"method",
"bodyType",
"body"
],
"properties": {
"body": {
"required": [
"query"
],
"properties": {
"type": {
"enum": [
"instant",
"fast",
"auto"
],
"type": "string",
"default": "auto",
"description": "Search mode: instant is lowest latency, fast adds page excerpts, auto picks per query."
},
"query": {
"type": "string",
"maxLength": 2000,
"minLength": 1,
"description": "What to search the web for."
},
"category": {
"type": "string",
"description": "Exa's category filter, e.g. news or research paper."
},
"contents": {
"type": "object",
"description": "Page contents to return with each result (text, highlights, summary)."
},
"numResults": {
"type": "integer",
"default": 10,
"maximum": 25,
"minimum": 1,
"description": "Results beyond 10 cost extra."
},
"endCrawlDate": {
"type": "string",
"description": "Only pages Exa crawled on or before this ISO 8601 date."
},
"userLocation": {
"type": "string",
"description": "Two-letter country code."
},
"excludeDomains": {
"type": "array",
"items": {
"type": "string"
},
"maxItems": 100,
"description": "Not these domains."
},
"includeDomains": {
"type": "array",
"items": {
"type": "string"
},
"maxItems": 100,
"description": "Only these domains."
},
"startCrawlDate": {
"type": "string",
"description": "Only pages Exa crawled on or after this ISO 8601 date."
},
"endPublishedDate": {
"type": "string",
"description": "Only pages published on or before this ISO 8601 date."
},
"startPublishedDate": {
"type": "string",
"description": "Only pages published on or after this ISO 8601 date."
}
}
},
"type": {
"type": "string",
"const": "http"
},
"method": {
"enum": [
"POST"
],
"type": "string"
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
}
},
"additionalProperties": false
},
"output": {
"type": "object",
"required": [
"type"
],
"properties": {
"type": {
"type": "string"
},
"example": {
"type": "object",
"required": [
"billing"
],
"properties": {
"billing": {
"type": "object",
"properties": {
"currency": {
"type": "string",
"const": "USDC"
},
"exaAtomic": {
"type": "string"
},
"feeAtomic": {
"type": "string"
},
"totalAtomic": {
"type": "string",
"description": "The amount settled"
},
"markupAtomic": {
"type": "string"
}
},
"description": "What was charged, in USDC micro-units"
}
}
}
}
}
}
}
},
"builder-code": {
"info": {
"a": "bc_is3fuv36"
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"a": {
"type": "string",
"pattern": "^[a-z0-9_]{1,32}$",
"description": "App builder code"
},
"s": {
"type": "array",
"items": {
"type": "string",
"pattern": "^[a-z0-9_]{1,32}$"
},
"maxItems": 11,
"description": "Service builder codes"
},
"w": {
"type": "string",
"pattern": "^[a-z0-9_]{1,32}$",
"description": "Wallet builder code"
}
},
"additionalProperties": false
}
}
},
"x402Version": 2
}Captured payload 6 of 7
{
"error": "Payment required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0xC23d1Dc0f5fCe1abfFB051e06cB93f0329968B4e",
"amount": "2000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 120
},
{
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"extra": {
"feePayer": "BENrLoUbndxoNMUS5JXApGMtNykLjFXXixMtpDwDR9SP"
},
"payTo": "4an2sqamWWhny9mjLsMtGXCDXakeNtg6vSLq4QvhdmQu",
"amount": "2000",
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 120
}
],
"resource": {
"url": "https://ask.singitai.app/v1/exa/contents",
"tags": [
"web-page-contents",
"web-scraping",
"page-contents",
"exa",
"web-search",
"pay-per-use",
"solana",
"base",
"singit"
],
"iconUrl": "https://singitai.app/assets/icons/icon-512.png",
"mimeType": "application/json",
"description": "Page contents API (Exa): text, highlights or a summary from up to 10 URLs. Pay per call in USDC on Base or Solana, no key. Exa list price plus $0.001.",
"serviceName": "SingIt Web Page Contents (Exa)"
},
"extensions": {
"bazaar": {
"info": {
"input": {
"body": {
"text": true,
"urls": [
"https://x402.org"
]
},
"type": "http",
"method": "POST",
"bodyType": "json"
},
"output": {
"type": "json",
"example": {
"billing": {
"currency": "USDC",
"exaAtomic": "1000",
"feeAtomic": "1000",
"totalAtomic": "2000",
"markupAtomic": "0"
},
"results": [
{
"id": "https://x402.org",
"url": "https://x402.org",
"text": "x402 is an open payment standard…",
"title": "x402"
}
],
"requestId": "example"
}
}
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"input"
],
"properties": {
"input": {
"type": "object",
"required": [
"type",
"method",
"bodyType",
"body"
],
"properties": {
"body": {
"properties": {
"ids": {
"type": "array",
"items": {
"type": "string"
},
"maxItems": 10,
"minItems": 1,
"description": "Exa result ids (1 to 10), instead of urls."
},
"text": {
"oneOf": [
{
"type": "boolean"
},
{
"type": "object"
}
],
"description": "Return the page text. Each kind asked for adds Exa's per-page price."
},
"urls": {
"type": "array",
"items": {
"type": "string"
},
"maxItems": 10,
"minItems": 1,
"description": "Pages to fetch (1 to 10). Send urls or ids, not both."
},
"summary": {
"oneOf": [
{
"type": "boolean"
},
{
"type": "object"
}
],
"description": "Return a summary. Each kind asked for adds Exa's per-page price."
},
"highlights": {
"oneOf": [
{
"type": "boolean"
},
{
"type": "object"
}
],
"description": "Return highlights. Each kind asked for adds Exa's per-page price."
},
"maxAgeHours": {
"type": "integer",
"description": "Accept a cached copy no older than this."
}
}
},
"type": {
"type": "string",
"const": "http"
},
"method": {
"enum": [
"POST"
],
"type": "string"
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
}
},
"additionalProperties": false
},
"output": {
"type": "object",
"required": [
"type"
],
"properties": {
"type": {
"type": "string"
},
"example": {
"type": "object",
"required": [
"billing"
],
"properties": {
"billing": {
"type": "object",
"properties": {
"currency": {
"type": "string",
"const": "USDC"
},
"exaAtomic": {
"type": "string"
},
"feeAtomic": {
"type": "string"
},
"totalAtomic": {
"type": "string",
"description": "The amount settled"
},
"markupAtomic": {
"type": "string"
}
},
"description": "What was charged, in USDC micro-units"
}
}
}
}
}
}
}
},
"builder-code": {
"info": {
"a": "bc_is3fuv36"
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"a": {
"type": "string",
"pattern": "^[a-z0-9_]{1,32}$",
"description": "App builder code"
},
"s": {
"type": "array",
"items": {
"type": "string",
"pattern": "^[a-z0-9_]{1,32}$"
},
"maxItems": 11,
"description": "Service builder codes"
},
"w": {
"type": "string",
"pattern": "^[a-z0-9_]{1,32}$",
"description": "Wallet builder code"
}
},
"additionalProperties": false
}
}
},
"x402Version": 2
}Captured payload 7 of 7
{
"error": "Payment required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0xC23d1Dc0f5fCe1abfFB051e06cB93f0329968B4e",
"amount": "6000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 120
},
{
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"extra": {
"feePayer": "BENrLoUbndxoNMUS5JXApGMtNykLjFXXixMtpDwDR9SP"
},
"payTo": "4an2sqamWWhny9mjLsMtGXCDXakeNtg6vSLq4QvhdmQu",
"amount": "6000",
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 120
}
],
"resource": {
"url": "https://ask.singitai.app/v1/exa/answer",
"tags": [
"web-search",
"answers",
"citations",
"exa",
"search",
"pay-per-use",
"solana",
"base",
"singit"
],
"iconUrl": "https://singitai.app/assets/icons/icon-512.png",
"mimeType": "application/json",
"description": "Cited web answer API (Exa): a sourced answer, not raw results. Pay per call in USDC on Base or Solana, no key. Exa list price plus $0.001.",
"serviceName": "SingIt Web Answers (Exa)"
},
"extensions": {
"bazaar": {
"info": {
"input": {
"body": {
"query": "What is x402?"
},
"type": "http",
"method": "POST",
"bodyType": "json"
},
"output": {
"type": "json",
"example": {
"answer": "x402 is an open standard for paying for an API call with a stablecoin over HTTP 402.",
"billing": {
"currency": "USDC",
"exaAtomic": "5000",
"feeAtomic": "1000",
"totalAtomic": "6000",
"markupAtomic": "0"
},
"citations": [
{
"id": "https://x402.org",
"url": "https://x402.org",
"title": "x402"
}
]
}
}
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"input"
],
"properties": {
"input": {
"type": "object",
"required": [
"type",
"method",
"bodyType",
"body"
],
"properties": {
"body": {
"required": [
"query"
],
"properties": {
"text": {
"type": "boolean",
"description": "Include the text of the cited pages."
},
"model": {
"enum": [
"exa",
"exa-fast"
],
"type": "string"
},
"query": {
"type": "string",
"maxLength": 2000,
"minLength": 1,
"description": "The question to answer with citations."
},
"systemPrompt": {
"type": "string",
"description": "Guidance for the answer's style."
},
"userLocation": {
"type": "string",
"description": "Two-letter country code."
}
}
},
"type": {
"type": "string",
"const": "http"
},
"method": {
"enum": [
"POST"
],
"type": "string"
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
}
},
"additionalProperties": false
},
"output": {
"type": "object",
"required": [
"type"
],
"properties": {
"type": {
"type": "string"
},
"example": {
"type": "object",
"required": [
"billing"
],
"properties": {
"billing": {
"type": "object",
"properties": {
"currency": {
"type": "string",
"const": "USDC"
},
"exaAtomic": {
"type": "string"
},
"feeAtomic": {
"type": "string"
},
"totalAtomic": {
"type": "string",
"description": "The amount settled"
},
"markupAtomic": {
"type": "string"
}
},
"description": "What was charged, in USDC micro-units"
}
}
}
}
}
}
}
},
"builder-code": {
"info": {
"a": "bc_is3fuv36"
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"a": {
"type": "string",
"pattern": "^[a-z0-9_]{1,32}$",
"description": "App builder code"
},
"s": {
"type": "array",
"items": {
"type": "string",
"pattern": "^[a-z0-9_]{1,32}$"
},
"maxItems": 11,
"description": "Service builder codes"
},
"w": {
"type": "string",
"pattern": "^[a-z0-9_]{1,32}$",
"description": "Wallet builder code"
}
},
"additionalProperties": false
}
}
},
"x402Version": 2
}Can I trust it score from our own monitoring
score from our own monitoring
97/100 Strong
#2 of 218 in AI. Bands: strong 93+, solid 75+, mixed 55+, weak below 55.
- Reliability
- 100% uptime since 11-04
- Compliance
- A 14/14 checks pass
- Price
- $0.0015 to $0.028117 p20 in AI
- Risk
- clean no risk flag
- Traction
- ---
14/14 compliance checks
- 402 payload captured
- accepts[] array present
- payTo address recoverable
- payTo at accepts[0].payTo (conformant shape)
- payTo is a valid on-chain address
- atomic price declared
- atomic price in a sane range
- asset (token) address declared
- network resolves to CAIP-2
- payment scheme declared
- served over HTTPS
- declares the current x402 version (2)
- EIP-712 domain parameters present on every EVM entry
- x402 v2 envelope delivered in the payment-required header
402 terms unchanged since 2026-11-04. Last up 2026-11-04.
── Site signals
- homepage reachable
- openapi doc
- pricing page
- llms.txt
- robots.txt
- terms page
How the score works
What the score read on this service: status online, 100% uptime, latest daily rollup (no 30d window yet), 404ms response p95, x402 compliance 14 of 14, $0.0015 price against the category. Each of those is measured, and each is published in full below.
The score comes from our own monitoring, never from reviews, operator claims, or a language model: reliability, x402 compliance, price against the category, a deterministic risk flag, and a small on-chain traction term, weighted by ranking generation 3. It is not placement anyone can buy: the paid verify tier is reported beside it and is not one of its inputs. Every component below stays published and read-only.
Bands on the 0 to 100 measured score: strong at 93 and above, solid from 75, mixed from 55, weak below 55. Price and speed are scored against the whole category field, every listing in it that carries no danger flag, the scored service included, so the score places a service in its own field.
It is a score inside AI, and only there: price and speed are scored against the whole category field, every listing in it that carries no danger flag, the scored service included, which here means 218 listings, this one among them: the same 218 the position above is counted against. When the two differ, the field is the wider one, because a listing we have measured too little of to rank still sits in the field the price and the speed are normalized over. The same service in a different field would read differently. The same engine answers GET /api/v1/best, and asked for a different pool (the whole directory, or another filter) it returns a different number for this service under this same ranking generation. Neither is more correct: they answer different questions, and the methodology states which is which.
All measured facts
What it does
OpenAI-compatible pay-per-answer chat across 100+ models (Claude, GPT, Gemini, Grok, DeepSeek, Qwen), plus image, speech and Exa search routes. Payment in USDC over x402 on Base or Solana; no API key or account needed. Unpaid requests return HTTP 402 with a PAYMENT-REQUIRED header. A free model is available to try.
SingIt Ask is a listed x402 AI API. Captured payment terms name Base, Solana. Monitoring and settlement figures below describe the observations available to this directory; an unpaid HTTP 402 check does not prove that a paid call will deliver.
Assessment computed at . Latest service check observed at . Service data JSON · Measurement methodology.
Page rendered at . This response time is separate from the observation and computation times attached to each measurement.
Latest endpoint observation: . Latest price capture: . Prices are recorded quotes, not a promise of availability. Token assets and payment terms are listed separately. Endpoint data JSON · Price history JSON · Measurement methodology.
Assessment computed at . Uptime uses the stated daily-rollup window; response times are in milliseconds, compliance is passed/evaluated checks, and traction is a measured settlement floor. The comparison score is out of 100 within this category. Assessment JSON · Measurement methodology.
Observed daily coverage: 2026-10-06 to 2026-11-04 UTC. Daily monitoring and settlement rollups do not expose their computation time; a bucket date is not an update timestamp. Uptime and response JSON · Volume JSON · Buyers JSON · Measurement methodology.
Ranked from the measured category pool, refreshed at most once a minute. The comparison has no persisted computation timestamp; the assessment time above belongs to this service only. Ranking API documentation · Ranking methodology.
x402 List home · Services · AI
- uptime · latest daily rollup
- -
- uptime 7d
- -
- uptime 30d
- -
- uptime 90d
- -
- response p95
- 404ms
- avg response
- 404ms
- total checks
- 1
Measured on the unpaid 402 handshake, not the paid call. A service can 402 correctly and still fail after payment.
- price (min)
- $0.0015
- price (max)
- $0.028117
- category percentile (min)
- p20 in AI
- category percentile (max)
- p42 in AI
- endpoints / prices
- 7 / 16
- model
- tiered
- stability
- 25%
No deterministic risk flag. Risk fires only on an exact blocklist match, or a reserved-brand name with a mismatched verified payTo. Never from low uptime, a high price, or a model guess.
- domain age
- -
- registrar
- -
- hosting
- custom
- domain created
- ---
Identity facts, not a risk score.
On-chain traction has not been assessed for this service yet.
- member since
- 2026-11-04
Recent checks
| Checked at (UTC) | Status | HTTP | Response | Endpoints |
|---|---|---|---|---|
| Online | 402 | 309ms | 7 | |
| Online | 402 | 217ms | 7 | |
| Online | 402 | 172ms | 7 | |
| Online | 402 | 209ms | 7 | |
| Online | 402 | 223ms | 7 | |
| Online | 402 | 131ms | 7 | |
| Online | 402 | 273ms | 7 | |
| Online | 402 | 404ms | 7 |
Changes0 in 30d
No changes recorded in the last 30 days.
Over time
On-chain volume
On-chain traction has not been assessed for this service yet.
Uptime no completed-day data
- Uptime
- no completed-day data
On-chain traction has not been assessed for this service yet.
More charts
Response time daily average, ms min 235ms, avg 235ms, max 235ms
10-06 to 11-04* UTC
Each series spans only the dates it has data for. Every series is also served as JSON at /api, /scores, /volume and /buyers.
Values
* today so far, partial (UTC).
The uptime summary counts completed UTC days only. The strip, readouts and table retain today's partial reading.
Assessment history last recorded at . Each UTC day uses its last recorded run; missing readings stay unmeasured. Assessment history JSON · Measurement methodology.
| Day | Uptime | Response | Compliance | Price percentile | Site signals |
|---|---|---|---|---|---|
| 2026-11-04* | 100% | 235.33ms | 14/14 | p20 | 4/6 |
Alternatives in AI
5 of 217 other ranked services in AI, ordered by the same measured score.
Own this service?
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HTML
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Markdown
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HTML, live uptime variant
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Delisting
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