diff --git a/internal/grammar/validator.go b/internal/grammar/validator.go
index 0d2900be..31ab5aad 100644
--- a/internal/grammar/validator.go
+++ b/internal/grammar/validator.go
@@ -13,6 +13,7 @@ import (
 
 	core "typefox.dev/fastbelt"
 	"typefox.dev/fastbelt/util/collections"
+	"typefox.dev/fastbelt/util/service"
 )
 
 const (
@@ -63,7 +64,7 @@ var reservedFieldNames = map[string]string{
 // GrammarImpl.Validate checks grammar-level constraints:
 //   - Rule names must be unique within the grammar.
 //   - Interface names must be unique within the grammar.
-func (g *GrammarImpl) Validate(_ context.Context, _ string, accept core.ValidationAcceptor) {
+func (g *GrammarImpl) Validate(_ context.Context, _ *service.Container, _ string, accept core.ValidationAcceptor) {
 	checkUniqueRuleNames(g, accept)
 	checkUniqueInterfaceNames(g, accept)
 }
@@ -129,7 +130,7 @@ func checkUniqueInterfaceNames(g Grammar, accept core.ValidationAcceptor) {
 
 // TokenImpl.Validate checks terminal rule constraints:
 //   - The regular expression should not match the empty string.
-func (t *TokenImpl) Validate(_ context.Context, _ string, accept core.ValidationAcceptor) {
+func (t *TokenImpl) Validate(_ context.Context, _ *service.Container, _ string, accept core.ValidationAcceptor) {
 	checkEmptyTerminalRule(t, accept)
 }
 
@@ -162,7 +163,7 @@ func checkEmptyTerminalRule(t Token, accept core.ValidationAcceptor) {
 //   - Keywords cannot be empty.
 //   - Keywords cannot consist only of whitespace.
 //   - Keywords should not contain whitespace characters (warning).
-func (k *KeywordImpl) Validate(_ context.Context, _ string, accept core.ValidationAcceptor) {
+func (k *KeywordImpl) Validate(_ context.Context, _ *service.Container, _ string, accept core.ValidationAcceptor) {
 	checkKeyword(k, accept)
 }
 
@@ -198,7 +199,7 @@ func checkKeyword(k Keyword, accept core.ValidationAcceptor) {
 	}
 }
 
-func (rule *ParserRuleImpl) Validate(ctx context.Context, _ string, accept core.ValidationAcceptor) {
+func (rule *ParserRuleImpl) Validate(ctx context.Context, _ *service.Container, _ string, accept core.ValidationAcceptor) {
 	checkRuleReturnType(rule, ctx, accept)
 }
 
@@ -224,7 +225,7 @@ func checkRuleReturnType(rule ParserRule, _ context.Context, accept core.Validat
 	}
 }
 
-func (i *InterfaceImpl) Validate(ctx context.Context, _ string, accept core.ValidationAcceptor) {
+func (i *InterfaceImpl) Validate(ctx context.Context, _ *service.Container, _ string, accept core.ValidationAcceptor) {
 	checkInterfaceExtends(i, ctx, accept)
 	checkInterfaceFieldNames(i, ctx, accept)
 	checkInterfaceFieldTypes(i, accept)
@@ -443,7 +444,7 @@ func appearsInExtends(target Interface, current Interface, ctx context.Context,
 	return false
 }
 
-func (r *RuleCallImpl) Validate(ctx context.Context, _ string, accept core.ValidationAcceptor) {
+func (r *RuleCallImpl) Validate(ctx context.Context, _ *service.Container, _ string, accept core.ValidationAcceptor) {
 	assignment := core.ContainerOfType[Assignment](r)
 	if assignment == nil {
 		// Some validations only apply to unassigned rule calls
@@ -518,7 +519,7 @@ func checkRuleCallPosition(call RuleCall, _ context.Context, accept core.Validat
 	}
 }
 
-func (a *ActionImpl) Validate(ctx context.Context, _ string, accept core.ValidationAcceptor) {
+func (a *ActionImpl) Validate(ctx context.Context, _ *service.Container, _ string, accept core.ValidationAcceptor) {
 	checkActionAssignmentType(a, ctx, accept)
 	checkActionPropertyType(a, ctx, accept)
 }
@@ -598,7 +599,7 @@ func checkActionPropertyType(a Action, ctx context.Context, accept core.Validati
 	}
 }
 
-func (a *AssignmentImpl) Validate(ctx context.Context, _ string, accept core.ValidationAcceptor) {
+func (a *AssignmentImpl) Validate(ctx context.Context, _ *service.Container, _ string, accept core.ValidationAcceptor) {
 	checkAssignmentType(a, ctx, accept)
 }
 
@@ -790,7 +791,7 @@ func doInterfaceIsAssignableTo(source Interface, target Interface, visited colle
 	return false
 }
 
-func (tg *TokenGroupImpl) Validate(_ context.Context, _ string, accept core.ValidationAcceptor) {
+func (tg *TokenGroupImpl) Validate(_ context.Context, _ *service.Container, _ string, accept core.ValidationAcceptor) {
 	checkRecursiveTokenGroup(tg, accept)
 	checkInvalidTokensInGroup(tg, accept)
 }
@@ -867,7 +868,7 @@ func checkInvalidTokensInGroup(tg TokenGroup, accept core.ValidationAcceptor) {
 //   - Operators must be keywords, tokens, or token groups (not hidden or
 //     comment tokens), and no operator may appear in two precedence groups.
 //   - The name of the generated operator token group must be available.
-func (rule *InfixRuleImpl) Validate(ctx context.Context, _ string, accept core.ValidationAcceptor) {
+func (rule *InfixRuleImpl) Validate(ctx context.Context, _ *service.Container, _ string, accept core.ValidationAcceptor) {
 	checkInfixNodeType(rule, ctx, accept)
 	checkInfixOperandRule(rule, ctx, accept)
 	checkInfixOperators(rule, ctx, accept)
@@ -1139,7 +1140,7 @@ func doFindInterfaceField(iface Interface, name string, ctx context.Context, vis
 	return nil
 }
 
-func (cr *CrossRefImpl) Validate(ctx context.Context, _ string, accept core.ValidationAcceptor) {
+func (cr *CrossRefImpl) Validate(ctx context.Context, _ *service.Container, _ string, accept core.ValidationAcceptor) {
 	checkCrossRefHasTerminal(cr, ctx, accept)
 	checkCrossRefToken(cr, ctx, accept)
 }
diff --git a/validation.go b/validation.go
index 7fbea268..0e804e4b 100644
--- a/validation.go
+++ b/validation.go
@@ -4,7 +4,11 @@
 
 package fastbelt
 
-import "context"
+import (
+	"context"
+
+	"typefox.dev/fastbelt/util/service"
+)
 
 // DiagnosticSeverity mirrors LSP DiagnosticSeverity values.
 type DiagnosticSeverity int
@@ -76,9 +80,10 @@ type ValidationAcceptor func(diagnostic *Diagnostic)
 // Validator can be implemented by AST node Impl structs to provide custom validation checks.
 type Validator interface {
 	// Validate performs validation on the receiver node.
+	// sc is the service container of the running language server.
 	// The level parameter identifies when validation runs (e.g. "on-type", "on-save").
 	// The accept callback is used to collect diagnostics.
-	Validate(ctx context.Context, level string, accept ValidationAcceptor)
+	Validate(ctx context.Context, sc *service.Container, level string, accept ValidationAcceptor)
 }
 
 // DiagnosticOption configures optional fields of a [Diagnostic] created by [NewDiagnostic].
diff --git a/workspace/document_validator.go b/workspace/document_validator.go
index 5c627062..5419b08d 100644
--- a/workspace/document_validator.go
+++ b/workspace/document_validator.go
@@ -58,7 +58,7 @@ func (s *DefaultDocumentValidator) Validate(ctx context.Context, doc *core.Docum
 			break
 		}
 		if validator, ok := node.(core.Validator); ok {
-			validator.Validate(ctx, level, accept)
+			validator.Validate(ctx, s.sc, level, accept)
 		}
 	}
 	return diagnostics