# Onchain & Trading Intelligence PubSub Poll

> Onchain & Trading Intelligence PubSub Poll is a paid API for AI agents from x402-services-production.up.railway.app, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-14).

Polls a named topic for new real-time onchain and trading intelligence messages using a secret token, returning messages with sequence numbers greater than a given value.

## Facts

- Endpoint: POST https://x402-services-production.up.railway.app/api/pubsub/poll
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/onchain-trading-intelligence-pubsub-poll-3b1ece9a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_XKJexlghsX203Dxr06o4G

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability onchain-trading-intelligence-pubsub-poll-3b1ece9a -d '<json body>'
```

Example prompt: Poll my onchain intelligence feed on the 'solana-snipes' topic using my token 'tok_abc123' and give me all messages since sequence 42.

## When to prefer this

Use this endpoint when you have already subscribed to a named intelligence topic and need to poll for new messages in a lightweight, stateful manner using a sequence cursor. Prefer this over one-shot query endpoints when you need continuous or recurring updates from a feed (e.g. snipe alerts, funding arb signals, dislocation radar) without re-querying the full dataset each time.

## Known failure modes

- Invalid or expired token returns authentication error
- Unknown topic name returns not found or empty result
- Missing required fields (token or topic) returns validation error
- No new messages since 'since' returns empty array
- Service downtime returns 5xx error
- Stale sequence number may return large backlog of messages

## How this service works

Pub/sub: fetch messages on a topic newer than a sequence number. Send { topic, token, since? }.

## Output

Returns an array of messages posted to the specified topic since the given sequence number, each containing real-time onchain or trading intelligence payloads (prices, alerts, signals, risk scores, etc.) along with their sequence identifiers for stateful polling continuity.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "token",
  "topic"
 ],
 "properties": {
  "since": {
   "type": "number",
   "description": "Return messages with seq greater than this"
  },
  "token": {
   "type": "string",
   "description": "Your secret token"
  },
  "topic": {
   "type": "string",
   "description": "Topic name"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/onchain-trading-intelligence-pubsub-poll-3b1ece9a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-services-production.up.railway.app](https://www.zero.xyz/host/x402-services-production.up.railway.app/llms.txt)