Pay-per-call chat completion on the small tier
Pay-per-call chat completion on the small tier. One request returns one assistant message, limited to 8000 input and 1024 output tokens, at 0.008 USDC per call on Base. Payment settles after the response is produced. A client nonce header makes a retry free of a second charge.
Answeringour last check, 2026-10-18
1 of 1checks answered this week
569 msmedian answer time
$0.008listed price per call
$0.008price it asked us
Paid test badge: not yet. The checks above are free: we call the tool without paying and read the payment request it sends back. The Verified badge needs paid calls whose answers match the promised output, and nobody can buy a badge.
Endpoint
POST https://pay.omnidev.tech/x402/chat-small
| Category | Market data |
|---|---|
| Provider host | pay.omnidev.tech |
| Networks | eip155:8453 |
| Payment schemes | exact |
| Self-reported calls, 30 days | 3 from 1 payers (the provider's figure, not ours) |
Our checks, last 30 days
| Day | Result | HTTP | Asked | Time |
|---|---|---|---|---|
| 2026-10-18 | valid payment request | 402 | $0.008 | 569 ms |
Example input (from the provider)
{
"body": {
"max_tokens": 64,
"messages": [
{
"content": "Summarize the x402 payment flow in one sentence.",
"role": "user"
}
]
},
"bodyType": "json",
"method": "POST",
"type": "http"
}
Promised output schema (from the provider)
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"body": {
"additionalProperties": false,
"properties": {
"max_tokens": {
"description": "Upper bound on output tokens.",
"maximum": 1024,
"minimum": 1,
"type": "integer"
},
"messages": {
"description": "Conversation, oldest first.",
"items": {
"additionalProperties": false,
"properties": {
"content": {
"description": "Message text.",
"type": "string"
},
"role": {
"enum": [
"system",
"developer",
"user",
"assistant"
],
"type": "string"
}
},
"required": [
"role",
"content"
],
"type": "object"
},
"maxItems": 64,
"minItems": 1,
"type": "array"
},
"model": {
"description": "auto selects the tier model.",
"enum": [
"auto",
"llama-3.1-8b",
"kimi-k3"
],
"type": "string"
},
"prompt": {
"description": "Shorthand for one user message; used when messages is absent.",
"type": "string"
}
},
"type": "object"
},
"bodyType": {
"enum": [
"json"
],
"type": "string"
},
"headers": {
"additionalProperties": {
"type": "string"
},
"properties": {
"X-Omni-Client-Nonce": {
"description": "Present on every request that carries a payment credential: a random base64url value, 22-128 characters, new for each payment. A paid request without it is answered 400 client_nonce_required and is not charged.",
"pattern": "^[A-Za-z0-9_-]{22,128}$",
"type": "string"
}
},
"type": "object"
},
"method": {
"enum": [
"POST"
],
"type": "string"
},
"type": {
"const": "http",
"type": "string"
}
},
"required": [
"type",
"method",
"bodyType",
"body"
],
"type": "object"
},
"output": {
"properties": {
"example": {
"properties": {
"facilitator_tx": {
"type": "string"
},
"ok": {
"type": "boolean"
},
"result": {
"properties": {
"choices": {
"type": "array"
},
"id": {
"type": "string"
},
"model": {
"type": "string"
},
"object": {
"type": "string"
},
"usage": {
"type": "object"
}
},
"required": [
"choices"
],
"type": "object"
},
"settled": {
"type": "boolean"
}
},
"required": [
"ok",
"result"
],
"type": "object"
},
"type": {
"const": "json",
"type": "string"
}
},
"required": [
"type"
],
"type": "object"
}
},
"required": [
"input"
],
"type": "object"
}