# 2s Knowledge Delta — Recent Events by Topic

> 2s Knowledge Delta — Recent Events by Topic is a paid API for AI agents from 2s.io, paid per call via x402, $0.06/call, status unknown (last checked 2026-09-15).

Returns a time-bounded list of significant real-world events (news, court cases, regulatory actions, etc.) for a given topic, sourced from structured data feeds like federal registers and court opinions.

## Facts

- Endpoint: POST https://2s.io/api/agent/knowledge-delta
- Price: $0.06/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/2s-knowledge-delta-recent-events-by-topic-50230377
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_OAZQBHEPzRArjsiomRqsM

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 2s-knowledge-delta-recent-events-by-topic-50230377 -d '<json body>'
```

Example prompt: What are the most significant SEC enforcement actions against crypto exchanges since January 1 2026? Give me up to 10 events through June 2026.

## When to prefer this

Use this endpoint when an AI agent needs structured, time-bounded summaries of real-world events on a specific topic — especially regulatory, legal, or policy domains. It is superior to general web search when you need structured output with significance scores and citable source URLs rather than raw HTML. Prefer it over news APIs when court opinions and federal register entries are relevant. Ideal for compliance monitoring, legal research, policy tracking, and regulatory change detection.

## Known failure modes

- Topic string too short or too long (outside 2-200 chars) — returns validation error
- Date range yields no matching events — returns empty items array with ok:true
- Invalid date format (not YYYY-MM-DD) — returns parsing error
- maxEvents out of range (0 or >50) — returns validation error
- Upstream data sources temporarily unavailable — may return partial results or 5xx error

## How this service works

The (most) everything API: 575+ pay-per-call endpoints for AI agents — ground-truth data, a full AI gateway, and agent infrastructure (storage, queues, watchers). USDC via x402, no signup, no API keys, and upto billing: pay actual usage, not the quote.

## Output

A JSON object containing an array of structured events, each with a date, title, summary, significance score (1-5), source label, and source URL. Also includes metadata about raw hits and which data sources were queried (e.g. federal-register, court-cases).

## Example request

```json
{
 "since": "2024-01-01",
 "topic": "artificial intelligence",
 "until": "2024-01-31",
 "maxEvents": 10
}
```

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "since": {
   "type": "string",
   "description": "Earliest date (YYYY-MM-DD)."
  },
  "topic": {
   "type": "string",
   "description": "Free-text domain of interest (2-200 chars)."
  },
  "until": {
   "type": "string",
   "description": "Latest date (YYYY-MM-DD); default today."
  },
  "maxEvents": {
   "type": "integer",
   "description": "Max events to return (1-50); default 20."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/2s-knowledge-delta-recent-events-by-topic-50230377/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from 2s.io](https://www.zero.xyz/host/2s.io/llms.txt)