diff --git a/internal/agent/canvas/loop_subgraph.go b/internal/agent/canvas/loop_subgraph.go
index 5b7eb1426..51ea1c9a3 100644
--- a/internal/agent/canvas/loop_subgraph.go
+++ b/internal/agent/canvas/loop_subgraph.go
@@ -37,6 +37,7 @@ package canvas
 import (
 	"context"
 	"fmt"
+	"slices"
 	"strings"
 
 	"ragflow/internal/agent/workflowx"
@@ -707,9 +708,9 @@ func evalDictOp(m map[string]any, op string, _ any) (bool, error) {
 func evalListOp(lst []any, op string, value any) (bool, error) {
 	switch op {
 	case "contains":
-		return listContains(lst, value), nil
+		return slices.Contains(lst, value), nil
 	case "not contains":
-		return !listContains(lst, value), nil
+		return !slices.Contains(lst, value), nil
 	case "is":
 		return listEqual(lst, value), nil
 	case "is not":
@@ -722,15 +723,6 @@ func evalListOp(lst []any, op string, value any) (bool, error) {
 	return false, fmt.Errorf("invalid operator: %s (list variable)", op)
 }
 
-func listContains(lst []any, value any) bool {
-	for _, x := range lst {
-		if x == value {
-			return true
-		}
-	}
-	return false
-}
-
 func listEqual(lst []any, value any) bool {
 	other, ok := value.([]any)
 	if !ok {
diff --git a/internal/agent/component/llm_test.go b/internal/agent/component/llm_test.go
index d041f1986..b977b96ec 100644
--- a/internal/agent/component/llm_test.go
+++ b/internal/agent/component/llm_test.go
@@ -15,6 +15,7 @@ package component
 import (
 	"context"
 	"errors"
+	"slices"
 	"testing"
 
 	"github.com/cloudwego/eino/schema"
@@ -178,14 +179,7 @@ func TestLLM_Invoke_InvokerError(t *testing.T) {
 
 func TestLLM_Registered(t *testing.T) {
 	names := RegisteredNames()
-	found := false
-	for _, n := range names {
-		if n == "llm" {
-			found = true
-			break
-		}
-	}
-	if !found {
+	if !slices.Contains(names, "llm") {
 		t.Fatalf("LLM not registered; names=%v", names)
 	}
 	// And a factory round-trip.
diff --git a/internal/agent/component/parallel_test.go b/internal/agent/component/parallel_test.go
index 16cca46bf..31ec3e1d2 100644
--- a/internal/agent/component/parallel_test.go
+++ b/internal/agent/component/parallel_test.go
@@ -35,6 +35,7 @@ package component
 
 import (
 	"context"
+	"slices"
 	"testing"
 )
 
@@ -45,14 +46,7 @@ import (
 // assert their absence here.
 func TestParallel_Registered(t *testing.T) {
 	names := RegisteredNames()
-	hasParallel := false
-	for _, n := range names {
-		if n == "parallel" {
-			hasParallel = true
-			break
-		}
-	}
-	if !hasParallel {
+	if !slices.Contains(names, "parallel") {
 		t.Errorf("Parallel not registered; RegisteredNames=%v", names)
 	}
 }
diff --git a/internal/cli/filesystem/skill_hub/source/clawhub.go b/internal/cli/filesystem/skill_hub/source/clawhub.go
index d62a74a21..d0b2f816f 100644
--- a/internal/cli/filesystem/skill_hub/source/clawhub.go
+++ b/internal/cli/filesystem/skill_hub/source/clawhub.go
@@ -25,6 +25,7 @@ import (
 	"net/http"
 	"path/filepath"
 	"regexp"
+	"slices"
 	"sort"
 	"strconv"
 	"strings"
@@ -905,24 +906,13 @@ func isSafePath(path string) bool {
 
 	// Check for parent directory references
 	parts := strings.Split(clean, string(filepath.Separator))
-	for _, part := range parts {
-		if part == ".." {
-			return false
-		}
-	}
-
-	return true
+	return !slices.Contains(parts, "..")
 }
 
 // isTextContent checks if content appears to be text (not binary)
 func isTextContent(data []byte) bool {
 	// Check for null bytes (indicates binary)
-	for _, b := range data {
-		if b == 0 {
-			return false
-		}
-	}
-	return true
+	return !slices.Contains(data, 0)
 }
 
 func min(a, b int) int {
diff --git a/internal/common/format.go b/internal/common/format.go
index b8be5970d..fbd8dfcb2 100644
--- a/internal/common/format.go
+++ b/internal/common/format.go
@@ -20,6 +20,7 @@ import (
 	"encoding/base64"
 	"fmt"
 	"regexp"
+	"slices"
 	"strconv"
 	"strings"
 	"time"
@@ -40,12 +41,7 @@ func IsCompositeModelName(modelName string) bool {
 	if len(parts) != 3 {
 		return false
 	}
-	for _, p := range parts {
-		if p == "" {
-			return false
-		}
-	}
-	return true
+	return !slices.Contains(parts, "")
 }
 
 func IsUUID(uuid string) bool {
@@ -68,10 +64,8 @@ func ExtractCompositeName(modelName string) (string, string, string, error) {
 	if len(parts) != 3 {
 		return "", "", "", fmt.Errorf("invalid model name format")
 	}
-	for _, p := range parts {
-		if p == "" {
-			return "", "", "", fmt.Errorf("invalid model name format")
-		}
+	if slices.Contains(parts, "") {
+		return "", "", "", fmt.Errorf("invalid model name format")
 	}
 	return parts[0], parts[1], parts[2], nil
 }
diff --git a/internal/engine/infinity/chunk.go b/internal/engine/infinity/chunk.go
index 6d6852e9c..efc3cbd52 100644
--- a/internal/engine/infinity/chunk.go
+++ b/internal/engine/infinity/chunk.go
@@ -2012,18 +2012,11 @@ func convertSelectFields(output []string, isSkillIndex ...bool) []string {
 
 	// Add id and empty count if needed
 	// For skill index, use skill_id instead of id
-	hasID := false
 	idField := "id"
 	if skillIndex {
 		idField = "skill_id"
 	}
-	for _, f := range result {
-		if f == idField {
-			hasID = true
-			break
-		}
-	}
-	if !hasID {
+	if !slices.Contains(result, idField) {
 		result = append([]string{idField}, result...)
 	}
 
diff --git a/internal/harness/core/callback.go b/internal/harness/core/callback.go
index 679082660..d9afc8e71 100644
--- a/internal/harness/core/callback.go
+++ b/internal/harness/core/callback.go
@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"io"
 	"reflect"
+	"slices"
 )
 
 // AgentCallbackInput is the input to the agent callback OnStart.
@@ -102,14 +103,7 @@ func filterOptions(name string, opts []RunOption) []RunOption {
 			tmp := &runOptions{}
 			fn(tmp)
 			if tmp.agentNames != nil {
-				match := false
-				for _, n := range tmp.agentNames {
-					if n == name {
-						match = true
-						break
-					}
-				}
-				if !match {
+				if !slices.Contains(tmp.agentNames, name) {
 					continue
 				}
 			}
@@ -152,14 +146,7 @@ func filterCallbackHandlersForNestedAgents(name string, opts []RunOption) []RunO
 			tmp := &runOptions{}
 			fn(tmp)
 			if tmp.agentNames != nil {
-				match := false
-				for _, n := range tmp.agentNames {
-					if n == name {
-						match = true
-						break
-					}
-				}
-				if !match {
+				if !slices.Contains(tmp.agentNames, name) {
 					continue
 				}
 			}
diff --git a/internal/harness/events/store.go b/internal/harness/events/store.go
index 0eba5c279..ead7549ef 100644
--- a/internal/harness/events/store.go
+++ b/internal/harness/events/store.go
@@ -2,6 +2,7 @@ package events
 
 import (
 	"context"
+	"slices"
 	"time"
 )
 
@@ -60,14 +61,7 @@ func (f EventFilter) Matches(e *Event) bool {
 		return false
 	}
 	if len(f.Types) > 0 {
-		matched := false
-		for _, t := range f.Types {
-			if e.Type == t {
-				matched = true
-				break
-			}
-		}
-		if !matched {
+		if !slices.Contains(f.Types, e.Type) {
 			return false
 		}
 	}
diff --git a/internal/harness/graph/graph/graph.go b/internal/harness/graph/graph/graph.go
index e4052880b..6aefa8747 100644
--- a/internal/harness/graph/graph/graph.go
+++ b/internal/harness/graph/graph/graph.go
@@ -4,6 +4,7 @@ package graph
 import (
 	"context"
 	"fmt"
+	"slices"
 
 	"ragflow/internal/harness/graph/channels"
 	"ragflow/internal/harness/graph/constants"
@@ -158,14 +159,7 @@ func (g *stateGraph) AddEdge(from, to string) error {
 		g.entryPoint = to
 	}
 	if to == constants.End {
-		found := false
-		for _, fp := range g.finishPoints {
-			if fp == from {
-				found = true
-				break
-			}
-		}
-		if !found {
+		if !slices.Contains(g.finishPoints, from) {
 			g.finishPoints = append(g.finishPoints, from)
 		}
 	}
diff --git a/internal/harness/graph/graph/message.go b/internal/harness/graph/graph/message.go
index b8881893b..c51d32614 100644
--- a/internal/harness/graph/graph/message.go
+++ b/internal/harness/graph/graph/message.go
@@ -3,6 +3,7 @@ package graph
 import (
 	"context"
 	"fmt"
+	"slices"
 
 	"ragflow/internal/harness/graph/channels"
 	"ragflow/internal/harness/graph/types"
@@ -398,14 +399,7 @@ func (f *MessagesFilter) Filter(msgs []*Message) []*Message {
 	for _, msg := range msgs {
 		// Check role filter
 		if len(f.roles) > 0 {
-			match := false
-			for _, role := range f.roles {
-				if msg.Role == role {
-					match = true
-					break
-				}
-			}
-			if !match {
+			if !slices.Contains(f.roles, msg.Role) {
 				continue
 			}
 		}
diff --git a/internal/harness/graph/pregel/write.go b/internal/harness/graph/pregel/write.go
index cb278b5ca..8ef7295e1 100644
--- a/internal/harness/graph/pregel/write.go
+++ b/internal/harness/graph/pregel/write.go
@@ -3,6 +3,7 @@ package pregel
 import (
 	"context"
 	"fmt"
+	"slices"
 	"sync"
 
 	"ragflow/internal/harness/graph/channels"
@@ -331,10 +332,8 @@ func NewNonNullWriteValidator(whitelist ...string) *NonNullWriteValidator {
 }
 
 func (v *NonNullWriteValidator) Validate(entry *ChannelWriteEntry) error {
-	for _, channel := range v.whitelist {
-		if entry.Channel == channel {
-			return nil
-		}
+	if slices.Contains(v.whitelist, entry.Channel) {
+		return nil
 	}
 
 	if entry.Value == nil {
diff --git a/internal/ingestion/compilation/extractor/dep_relation.go b/internal/ingestion/compilation/extractor/dep_relation.go
index c0153305a..aacb9b8a9 100644
--- a/internal/ingestion/compilation/extractor/dep_relation.go
+++ b/internal/ingestion/compilation/extractor/dep_relation.go
@@ -4,7 +4,11 @@
 
 package extractor
 
-import "strings"
+import (
+	"slices"
+	"strings"
+)
+
 
 // Verb lemmatization — multi-language
 var verbLemma = map[string]string{
@@ -617,15 +621,15 @@ func extractCopula(text string, rootIdx int, tokens []DepToken, entityMap map[st
 	var prepObj *Entity
 
 	for _, c := range childrenOf(rootIdx, tokens) {
-		if !containsDep(c.Dep, cd.attrDeps) {
+		if !slices.Contains(cd.attrDeps, c.Dep) {
 			continue
 		}
 		for _, cc := range childrenOf(c.Index, tokens) {
-			if !containsDep(cc.Dep, cd.prepDeps) {
+			if !slices.Contains(cd.prepDeps, cc.Dep) {
 				continue
 			}
 			for _, gc := range childrenOf(cc.Index, tokens) {
-				if containsDep(gc.Dep, cd.objDeps) {
+				if slices.Contains(cd.objDeps, gc.Dep) {
 					if ent := findEntityInSubtree(gc.Index, tokens, entityMap); ent != nil {
 						prepObj = ent
 						titleLemma = strings.ToLower(c.Text)
@@ -678,15 +682,6 @@ func lookupVerb(verb, prep string) string {
 	return depVerbRelations[verb]
 }
 
-func containsDep(dep string, deps []string) bool {
-	for _, d := range deps {
-		if dep == d {
-			return true
-		}
-	}
-	return false
-}
-
 func childrenOf(idx int, tokens []DepToken) []DepToken {
 	var kids []DepToken
 	for _, t := range tokens {
diff --git a/internal/service/nlp/term_weight_test.go b/internal/service/nlp/term_weight_test.go
index a1efea53d..078e5b000 100644
--- a/internal/service/nlp/term_weight_test.go
+++ b/internal/service/nlp/term_weight_test.go
@@ -18,6 +18,7 @@ import (
 	"os"
 	"path/filepath"
 	"reflect"
+	"slices"
 	"strings"
 	"testing"
 )
@@ -713,14 +714,7 @@ func TestPretokenWithNumbers(t *testing.T) {
 	t.Run("num=false filters single digits", func(t *testing.T) {
 		result := d.Pretoken("5", false, true)
 		// Single digit should be filtered when num=false
-		found := false
-		for _, r := range result {
-			if r == "5" {
-				found = true
-				break
-			}
-		}
-		if found {
+		if slices.Contains(result, "5") {
 			t.Error("Single digit should be filtered when num=false")
 		}
 	})
diff --git a/internal/service/nlp/wordnet_test.go b/internal/service/nlp/wordnet_test.go
index be4fc784f..5a88d7586 100644
--- a/internal/service/nlp/wordnet_test.go
+++ b/internal/service/nlp/wordnet_test.go
@@ -20,6 +20,7 @@ import (
 	"os"
 	"path/filepath"
 	"reflect"
+	"slices"
 	"sort"
 	"testing"
 )
@@ -122,14 +123,7 @@ func TestSynsets(t *testing.T) {
 				names[i] = s.Name
 			}
 			for _, expectedName := range tt.checkNames {
-				found := false
-				for _, name := range names {
-					if name == expectedName {
-						found = true
-						break
-					}
-				}
-				if !found {
+				if !slices.Contains(names, expectedName) {
 					t.Errorf("Synsets(%q, %q) did not contain expected synset %q, got %v",
 						tt.lemma, tt.pos, expectedName, names)
 				}
diff --git a/internal/utility/ssrf.go b/internal/utility/ssrf.go
index c837f981a..74a39c3d0 100644
--- a/internal/utility/ssrf.go
+++ b/internal/utility/ssrf.go
@@ -22,6 +22,7 @@ import (
 	"net"
 	"net/http"
 	"net/url"
+	"slices"
 	"sort"
 	"strings"
 	"time"
@@ -69,7 +70,7 @@ func AssertURLSafe(rawURL string) (hostname, resolvedIP string, err error) {
 	}
 
 	scheme := strings.ToLower(parsed.Scheme)
-	if !schemeAllowed(scheme) {
+	if !slices.Contains(AllowedURLSchemes, scheme) {
 		sorted := append([]string(nil), AllowedURLSchemes...)
 		sort.Strings(sorted)
 		return "", "", fmt.Errorf("disallowed URL scheme: '%s'. Only %v are allowed", scheme, sorted)
@@ -104,15 +105,6 @@ func AssertURLSafe(rawURL string) (hostname, resolvedIP string, err error) {
 	return hostname, resolvedIP, nil
 }
 
-func schemeAllowed(scheme string) bool {
-	for _, s := range AllowedURLSchemes {
-		if s == scheme {
-			return true
-		}
-	}
-	return false
-}
-
 // effectiveIP unwraps IPv4-mapped IPv6 addresses (e.g. ::ffff:127.0.0.1) so
 // the routability check sees the IPv4 form. Without this, an attacker could
 // bypass the guard with an IPv4-mapped IPv6 representation of a private host.