# Predge Kalshi Market Outcome Attestation

> Predge Kalshi Market Outcome Attestation is a paid API for AI agents from api.predge.io, paid per call via x402, $0.02/call, status unknown (last checked 2026-09-15).

Returns a cryptographically signed (ed25519) attestation of a Kalshi prediction market's settled resolution, verifiable offline.

## Facts

- Endpoint: GET https://api.predge.io/v1/kalshi/attest/:ticker
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/predge-kalshi-market-outcome-attestation-13c751b9
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Hv470ENeq6BA_4ZmVA65q

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 predge-kalshi-market-outcome-attestation-13c751b9
```

Example prompt: Can you get me a signed, offline-verifiable attestation of how the Kalshi market KXBTC-23DEC31-B30000 resolved — and check whether the 'yes' side was correct?

## When to prefer this

Use this endpoint when you need cryptographic, offline-verifiable proof of a Kalshi market outcome — especially for smart contracts, trustless settlement workflows, or audit trails where trusting a raw API response is insufficient. Prefer this over querying Kalshi directly when you need a signed attestation rather than plain data, or when you want to verify a specific side's correctness in a single call.

## Known failure modes

- 404 returned for unknown or non-existent Kalshi ticker (not charged)
- resolved:false with null resolution/resolved_at when market exists but has not yet settled
- Stale data if Kalshi's public API is delayed or temporarily unavailable
- Signature verification failure if the published key has rotated and client cache is stale

## How this service works

Cryptographically SIGNED settled-KALSHI-outcome ATTESTATION for one market (path param: ticker, a Kalshi market ticker). Returns the market's SETTLED resolution (resolved, resolution yes|no, resolved_at) as an ed25519-signed envelope verifiable OFFLINE against the SAME published key as /v1/attest. Optional query param: side (yes|no) — adds correct (true iff it matches the resolution, null while unsettled). Data source: Kalshi's public market API (no key, no account); this attests the MARKET's own result, NOT trader data. A market that exists but has not settled returns resolved:false. 404 (not charged) for an unknown ticker.

## Output

A JSON envelope containing resolved (true/false), resolution ('yes' or 'no' if settled), resolved_at (ISO timestamp if settled), an ed25519 signature over the payload verifiable against Predge's published public key, and optionally a 'correct' boolean if a 'side' query param was supplied. Unsettled markets return resolved:false with null resolution fields. Unknown tickers return a 404 with no charge.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "pathParams": {
     "type": "object"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "side": {
       "enum": [
        "yes",
        "no"
       ],
       "type": "string",
       "description": "Optional side to check correctness for"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/predge-kalshi-market-outcome-attestation-13c751b9/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.predge.io](https://www.zero.xyz/host/api.predge.io/llms.txt)