USDA Livestock Price Anomaly Alerts — did this market's price just move?

An independent tool. It is not affiliated with, endorsed by, or operated by USDA or the Agricultural Marketing Service. USDA Market News reports are US government works (17 U.S.C. §105) and AMS's own privacy statement describes information on its site as "considered public information and may be distributed or copied." This Actor reads AMS's MARS API and reports what it returns, reshaped into a period-over-period alert.

No scraper. This Actor never touches a USDA web page's HTML. Its data comes from AMS's MARS API (marsapi.ams.usda.gov), refreshed on a schedule and bundled into this Actor at build time.

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Why this exists

Checking whether this week's price at a sale barn moved sharply from last time means reading that market's own report history yourself, market by market, and doing the arithmetic by hand. This Actor does that arithmetic for you and only tells you when it crosses a threshold you set — a real alert, not a raw feed you still have to watch.

v1 covers 6 livestock-auction markets — Unionville Livestock Market (MO), Oklahoma National Stockyards (OK), Huss Livestock (NE), Frisco City Stockyards (AL), Athens Regional Stockyard (TN), and Lexington Livestock Auction (KY) — for Feeder Cattle, Steers or Heifers, Per Cwt, across the common 400-900 lb weight breaks — the same markets and slice the sibling comparison product (usda-livestock-price-comparison) already found report densely and consistently enough to support this kind of analysis.

What you give it

• market_report_slugs — which of the 6 covered markets to watch (their AMS report slug ids).
• commodity, animal_class, weight_break_low, weight_break_high, price_unit — the ONE group to watch (v1: Feeder Cattle, Steers/Heifers, common weight breaks, Per Cwt).
• anomaly_threshold_pct — how large a move (in percent) counts as an alert. Default 10, set from this product's own measurement on real 2025-2026 data (median week-over-week move 5.0%, about 17% of periods moved 10% or more).

What comes back

One row per requested market: its most recent period-over-period price change for the requested group (the two report dates compared, the two average prices, the percent change, the direction), whether it crossed your threshold (is_anomaly), and how many report dates were available to judge it from. A market with too little recent history, or a quiet period, still gets a row — charged: false with a plain-English not_charged_reason — never a silent gap.

Billing

Charged only for a real alert — a period-over-period move that actually crossed your threshold (price-anomaly-alert-delivered). A quiet period or a market with fewer than two comparable recent reports is delivered free, with a reason. You pay for signal, not for every check.

Data freshness

The alert is only as current as the last scheduled refresh. Each market's own most recent report dates for the requested group are kept; the period-over-period comparison always uses the two most recent of those.

A note on scope

Only "Per Cwt" (per-hundredweight) prices are compared. AMS reports the same commodity/class/weight combination under other price units too ("Per Head", "Per Unit", "Per Family") — mixing them produces nonsense swings (this Actor's own development found +895%/+797% fake moves this way before the fix). Every group this Actor compares is pinned to one price unit at a time, by construction.