fix: apply price range filter to YES only, not NO

MIN/MAX_PRICE was filtering both YES and NO bids, blocking valid
skewed-market entries like YES=11c + NO=87c (NO fails MAX_PRICE=0.30).

Now only YES is range-checked. NO only needs basic sanity bounds (0 < noBid < 1).
This enables targeting cheap YES markets while NO bid can be any value.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.env.example

@@ -95,8 +95,10 @@ MAKER_MM_REENTRY_DELAY=30
 # Set to false to disable re-entry — bot places one order per market then waits for next
 MAKER_MM_REENTRY_ENABLED=true
 
-# Price range for maker rebate eligibility (both sides must be in range)
+# YES bid price range — bot only enters when YES bid is within this range.
-# Polymarket rebates are earned on orders within ~30-70% range
+# NO bid is derived from MAX_COMBINED - YES bid, and is NOT range-filtered.
+# Default (balanced market): 0.30-0.69 — enters near 50/50
+# Skewed market mode:        0.10-0.30 — only enters when YES is cheap (e.g. YES=11c, NO=87c)
 MAKER_MM_MIN_PRICE=0.30
 MAKER_MM_MAX_PRICE=0.69
 

src/services/makerRebateExecutor.js

@@ -642,9 +642,11 @@ export async function executeMakerRebateStrategy(market) {
         // Safety: ensure NO is also strictly below NO ask (maker)
         if (noAsk && noBid >= noAsk) noBid = roundToTick(noAsk - ts, tickSize);
 
-        // Range check on NO bid
+        // Sanity check on NO bid — only basic bounds, no range filter.
-        if (noBid < MIN_PRICE || noBid > MAX_PRICE) {
+        // MIN/MAX_PRICE applies to YES only (entry condition), not NO.
-            logger.info(`MakerMM${tag}: waiting — NO bid $${noBid.toFixed(3)} (need ${MIN_PRICE}-${MAX_PRICE})`);
+        // e.g. YES=11c + NO=87c is valid even though NO > MAX_PRICE.
+        if (noBid <= 0 || noBid >= 1) {
+            logger.info(`MakerMM${tag}: waiting — NO bid $${noBid.toFixed(3)} out of bounds`);
             await sleep(POLL_SEC * 1000);
             continue;
         }