diff --git a/decision/engine.go b/decision/engine.go
index a96db8aa..ddf0568a 100644
--- a/decision/engine.go
+++ b/decision/engine.go
@@ -278,6 +278,8 @@ func GetFullDecisionWithStrategy(ctx *Context, mcpClient mcp.AIClient, engine *S
 		ctx.Account.TotalEquity,
 		riskConfig.BTCETHMaxLeverage,
 		riskConfig.AltcoinMaxLeverage,
+		riskConfig.BTCETHMaxPositionValueRatio,
+		riskConfig.AltcoinMaxPositionValueRatio,
 	)
 
 	if decision != nil {
@@ -1297,7 +1299,7 @@ func formatFloatSlice(values []float64) string {
 // AI Response Parsing
 // ============================================================================
 
-func parseFullDecisionResponse(aiResponse string, accountEquity float64, btcEthLeverage, altcoinLeverage int) (*FullDecision, error) {
+func parseFullDecisionResponse(aiResponse string, accountEquity float64, btcEthLeverage, altcoinLeverage int, btcEthPosRatio, altcoinPosRatio float64) (*FullDecision, error) {
 	cotTrace := extractCoTTrace(aiResponse)
 
 	decisions, err := extractDecisions(aiResponse)
@@ -1308,7 +1310,7 @@ func parseFullDecisionResponse(aiResponse string, accountEquity float64, btcEthL
 		}, fmt.Errorf("failed to extract decisions: %w", err)
 	}
 
-	if err := validateDecisions(decisions, accountEquity, btcEthLeverage, altcoinLeverage); err != nil {
+	if err := validateDecisions(decisions, accountEquity, btcEthLeverage, altcoinLeverage, btcEthPosRatio, altcoinPosRatio); err != nil {
 		return &FullDecision{
 			CoTTrace:  cotTrace,
 			Decisions: decisions,
@@ -1474,16 +1476,16 @@ func compactArrayOpen(s string) string {
 // Decision Validation
 // ============================================================================
 
-func validateDecisions(decisions []Decision, accountEquity float64, btcEthLeverage, altcoinLeverage int) error {
+func validateDecisions(decisions []Decision, accountEquity float64, btcEthLeverage, altcoinLeverage int, btcEthPosRatio, altcoinPosRatio float64) error {
 	for i, decision := range decisions {
-		if err := validateDecision(&decision, accountEquity, btcEthLeverage, altcoinLeverage); err != nil {
+		if err := validateDecision(&decision, accountEquity, btcEthLeverage, altcoinLeverage, btcEthPosRatio, altcoinPosRatio); err != nil {
 			return fmt.Errorf("decision #%d validation failed: %w", i+1, err)
 		}
 	}
 	return nil
 }
 
-func validateDecision(d *Decision, accountEquity float64, btcEthLeverage, altcoinLeverage int) error {
+func validateDecision(d *Decision, accountEquity float64, btcEthLeverage, altcoinLeverage int, btcEthPosRatio, altcoinPosRatio float64) error {
 	validActions := map[string]bool{
 		"open_long":   true,
 		"open_short":  true,
@@ -1499,10 +1501,12 @@ func validateDecision(d *Decision, accountEquity float64, btcEthLeverage, altcoi
 
 	if d.Action == "open_long" || d.Action == "open_short" {
 		maxLeverage := altcoinLeverage
-		maxPositionValue := accountEquity * 1.5
+		posRatio := altcoinPosRatio
+		maxPositionValue := accountEquity * posRatio
 		if d.Symbol == "BTCUSDT" || d.Symbol == "ETHUSDT" {
 			maxLeverage = btcEthLeverage
-			maxPositionValue = accountEquity * 10
+			posRatio = btcEthPosRatio
+			maxPositionValue = accountEquity * posRatio
 		}
 
 		if d.Leverage <= 0 {
@@ -1533,9 +1537,9 @@ func validateDecision(d *Decision, accountEquity float64, btcEthLeverage, altcoi
 		tolerance := maxPositionValue * 0.01
 		if d.PositionSizeUSD > maxPositionValue+tolerance {
 			if d.Symbol == "BTCUSDT" || d.Symbol == "ETHUSDT" {
-				return fmt.Errorf("BTC/ETH single coin position value cannot exceed %.0f USDT (10x account equity), actual: %.0f", maxPositionValue, d.PositionSizeUSD)
+				return fmt.Errorf("BTC/ETH single coin position value cannot exceed %.0f USDT (%.1fx account equity), actual: %.0f", maxPositionValue, posRatio, d.PositionSizeUSD)
 			} else {
-				return fmt.Errorf("altcoin single coin position value cannot exceed %.0f USDT (1.5x account equity), actual: %.0f", maxPositionValue, d.PositionSizeUSD)
+				return fmt.Errorf("altcoin single coin position value cannot exceed %.0f USDT (%.1fx account equity), actual: %.0f", maxPositionValue, posRatio, d.PositionSizeUSD)
 			}
 		}
 		if d.StopLoss <= 0 || d.TakeProfit <= 0 {
diff --git a/decision/validate_test.go b/decision/validate_test.go
index 3f2da737..a04f1642 100644
--- a/decision/validate_test.go
+++ b/decision/validate_test.go
@@ -83,7 +83,8 @@ func TestLeverageFallback(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			err := validateDecision(&tt.decision, tt.accountEquity, tt.btcEthLeverage, tt.altcoinLeverage)
+			// Use default position value ratios for testing (10x for BTC/ETH, 1.5x for altcoins)
+			err := validateDecision(&tt.decision, tt.accountEquity, tt.btcEthLeverage, tt.altcoinLeverage, 10.0, 1.5)
 
 			// Check error status
 			if (err != nil) != tt.wantError {