PredictIt API latency

PredictIt is a CFTC-regulated US political prediction market probed at 15-second intervals due to its published rate limit of 5 requests per minute. The harness targets the single-market endpoint /api/marketdata/markets/{id} for price probes and records the full round trip. Because the probe cadence is 3 times slower than other venues in the cohort, PredictIt's latency samples are fewer and the p50 reflects fewer data points per hour. No book endpoint exists on their API; the closest equivalent (the all-markets snapshot at /api/marketdata/all) is also probed at 15s for the list class.