diff --git a/optimizer/src/main/java/dev/cel/optimizer/optimizers/SelectOptimizer.java b/optimizer/src/main/java/dev/cel/optimizer/optimizers/SelectOptimizer.java
index 3c6097180..56d662237 100644
--- a/optimizer/src/main/java/dev/cel/optimizer/optimizers/SelectOptimizer.java
+++ b/optimizer/src/main/java/dev/cel/optimizer/optimizers/SelectOptimizer.java
@@ -58,32 +58,36 @@
 import dev.cel.common.types.CelKind;
 import dev.cel.common.types.CelTypes;
 import dev.cel.common.types.ListType;
+import dev.cel.common.types.MapType;
 import dev.cel.common.types.SimpleType;
+import dev.cel.common.types.StructTypeReference;
 import dev.cel.common.values.CelByteString;
 import dev.cel.optimizer.AstMutator;
 import dev.cel.optimizer.CelAstOptimizer;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
+import java.util.LinkedHashMap;
 import java.util.List;
+import java.util.Map;
 import java.util.Optional;
 
 /**
  * Performs field selection optimization on protobuf message select chains.
  *
- * <p>Embeds protobuf field metadata directly into qualification paths ({@code cel.@attribute}) and
- * field presence paths ({@code cel.@hasField}). This accelerates nested field evaluation, enables
- * reflection-free field traversal in resource-constrained runtimes without descriptor tables, and
- * provides resilience against protobuf field renames.
+ * <p>Embeds protobuf field metadata directly into qualification paths ({@code
+ * cel.@attribute<Type>}) and field presence paths ({@code cel.@hasField}). This accelerates nested
+ * field evaluation, enables reflection-free field traversal in resource-constrained runtimes
+ * without descriptor tables, and provides resilience against protobuf field renames.
  *
  * <p><b>WARNING:</b> Evaluating optimized ASTs requires explicit runtime support for {@code
- * cel.@attribute} and {@code cel.@hasField}. Ensure that the target evaluation environment (in
- * Java, C++, Go, or other language runtimes) supports these select optimization functions before
- * applying this optimizer. Evaluating an optimized AST in an unsupported runtime will result in an
- * evaluation error due to missing function overloads.
+ * cel.@attribute<Type>} and {@code cel.@hasField}. Ensure that the target evaluation environment
+ * (in Java, C++, Go, or other language runtimes) supports these select optimization functions
+ * before applying this optimizer. Evaluating an optimized AST in an unsupported runtime will result
+ * in an evaluation error due to missing function overloads.
  *
- * <p><b>Metadata Tuples:</b> In {@code cel.@attribute}, each step in the qualification path is
- * represented as a metadata tuple:
+ * <p><b>Metadata Tuples:</b> In {@code cel.@attribute<Type>}, each step in the qualification path
+ * is represented as a metadata tuple:
  *
  * <ul>
  *   <li>Scalar fields, repeated fields, maps, and well-known types (timestamp, duration) include
@@ -104,7 +108,7 @@
  *
  * <pre>
  *   // Selection chains (user message is 3-tuple, leaf scalar is 4-tuple)
- *   request.user.age -&gt; cel.@attribute(request,
+ *   request.user.age -&gt; cel.@attributeInt(request,
  *       [[user_num, "user", type_code], [age_num, "age", type_code, default_val]])
  *
  *   // Presence tests (2-tuples)
@@ -124,16 +128,107 @@ public final class SelectOptimizer implements CelAstOptimizer {
    */
   private static final long CEL_MAP_TYPE_CODE = 20L;
 
-  private static final String CEL_ATTRIBUTE_FUNCTION_NAME = "cel.@attribute";
+  private static final String CEL_ATTRIBUTE_INT_FUNCTION_NAME = "cel.@attributeInt";
+  private static final String CEL_ATTRIBUTE_UINT_FUNCTION_NAME = "cel.@attributeUint";
+  private static final String CEL_ATTRIBUTE_DOUBLE_FUNCTION_NAME = "cel.@attributeDouble";
+  private static final String CEL_ATTRIBUTE_BOOL_FUNCTION_NAME = "cel.@attributeBool";
+  private static final String CEL_ATTRIBUTE_STRING_FUNCTION_NAME = "cel.@attributeString";
+  private static final String CEL_ATTRIBUTE_BYTES_FUNCTION_NAME = "cel.@attributeBytes";
+  private static final String CEL_ATTRIBUTE_DURATION_FUNCTION_NAME = "cel.@attributeDuration";
+  private static final String CEL_ATTRIBUTE_TIMESTAMP_FUNCTION_NAME = "cel.@attributeTimestamp";
+  private static final String CEL_ATTRIBUTE_LIST_FUNCTION_NAME = "cel.@attributeList";
+  private static final String CEL_ATTRIBUTE_MAP_FUNCTION_NAME = "cel.@attributeMap";
+  private static final String CEL_ATTRIBUTE_MESSAGE_FUNCTION_PREFIX = "cel.@attributeMessage:";
   private static final String CEL_HAS_FIELD_FUNCTION_NAME = "cel.@hasField";
 
   @VisibleForTesting
-  static final CelFunctionDecl CEL_ATTRIBUTE_FUNCTION_DECL =
+  static final CelFunctionDecl CEL_ATTRIBUTE_INT_FUNCTION_DECL =
       CelFunctionDecl.newFunctionDeclaration(
-          CEL_ATTRIBUTE_FUNCTION_NAME,
+          CEL_ATTRIBUTE_INT_FUNCTION_NAME,
           CelOverloadDecl.newGlobalOverload(
-              "cel_attribute_list",
+              "cel_attribute_int_list",
+              SimpleType.INT,
               SimpleType.DYN,
+              ListType.create(SimpleType.DYN)));
+
+  private static final CelFunctionDecl CEL_ATTRIBUTE_UINT_FUNCTION_DECL =
+      CelFunctionDecl.newFunctionDeclaration(
+          CEL_ATTRIBUTE_UINT_FUNCTION_NAME,
+          CelOverloadDecl.newGlobalOverload(
+              "cel_attribute_uint_list",
+              SimpleType.UINT,
+              SimpleType.DYN,
+              ListType.create(SimpleType.DYN)));
+
+  private static final CelFunctionDecl CEL_ATTRIBUTE_DOUBLE_FUNCTION_DECL =
+      CelFunctionDecl.newFunctionDeclaration(
+          CEL_ATTRIBUTE_DOUBLE_FUNCTION_NAME,
+          CelOverloadDecl.newGlobalOverload(
+              "cel_attribute_double_list",
+              SimpleType.DOUBLE,
+              SimpleType.DYN,
+              ListType.create(SimpleType.DYN)));
+
+  private static final CelFunctionDecl CEL_ATTRIBUTE_BOOL_FUNCTION_DECL =
+      CelFunctionDecl.newFunctionDeclaration(
+          CEL_ATTRIBUTE_BOOL_FUNCTION_NAME,
+          CelOverloadDecl.newGlobalOverload(
+              "cel_attribute_bool_list",
+              SimpleType.BOOL,
+              SimpleType.DYN,
+              ListType.create(SimpleType.DYN)));
+
+  private static final CelFunctionDecl CEL_ATTRIBUTE_STRING_FUNCTION_DECL =
+      CelFunctionDecl.newFunctionDeclaration(
+          CEL_ATTRIBUTE_STRING_FUNCTION_NAME,
+          CelOverloadDecl.newGlobalOverload(
+              "cel_attribute_string_list",
+              SimpleType.STRING,
+              SimpleType.DYN,
+              ListType.create(SimpleType.DYN)));
+
+  private static final CelFunctionDecl CEL_ATTRIBUTE_BYTES_FUNCTION_DECL =
+      CelFunctionDecl.newFunctionDeclaration(
+          CEL_ATTRIBUTE_BYTES_FUNCTION_NAME,
+          CelOverloadDecl.newGlobalOverload(
+              "cel_attribute_bytes_list",
+              SimpleType.BYTES,
+              SimpleType.DYN,
+              ListType.create(SimpleType.DYN)));
+
+  private static final CelFunctionDecl CEL_ATTRIBUTE_DURATION_FUNCTION_DECL =
+      CelFunctionDecl.newFunctionDeclaration(
+          CEL_ATTRIBUTE_DURATION_FUNCTION_NAME,
+          CelOverloadDecl.newGlobalOverload(
+              "cel_attribute_duration_list",
+              SimpleType.DURATION,
+              SimpleType.DYN,
+              ListType.create(SimpleType.DYN)));
+
+  private static final CelFunctionDecl CEL_ATTRIBUTE_TIMESTAMP_FUNCTION_DECL =
+      CelFunctionDecl.newFunctionDeclaration(
+          CEL_ATTRIBUTE_TIMESTAMP_FUNCTION_NAME,
+          CelOverloadDecl.newGlobalOverload(
+              "cel_attribute_timestamp_list",
+              SimpleType.TIMESTAMP,
+              SimpleType.DYN,
+              ListType.create(SimpleType.DYN)));
+
+  private static final CelFunctionDecl CEL_ATTRIBUTE_LIST_FUNCTION_DECL =
+      CelFunctionDecl.newFunctionDeclaration(
+          CEL_ATTRIBUTE_LIST_FUNCTION_NAME,
+          CelOverloadDecl.newGlobalOverload(
+              "cel_attribute_list_list",
+              ListType.create(SimpleType.DYN),
+              SimpleType.DYN,
+              ListType.create(SimpleType.DYN)));
+
+  private static final CelFunctionDecl CEL_ATTRIBUTE_MAP_FUNCTION_DECL =
+      CelFunctionDecl.newFunctionDeclaration(
+          CEL_ATTRIBUTE_MAP_FUNCTION_NAME,
+          CelOverloadDecl.newGlobalOverload(
+              "cel_attribute_map_list",
+              MapType.create(SimpleType.DYN, SimpleType.DYN),
               SimpleType.DYN,
               ListType.create(SimpleType.DYN)));
 
@@ -147,6 +242,20 @@ public final class SelectOptimizer implements CelAstOptimizer {
               SimpleType.DYN,
               ListType.create(SimpleType.DYN)));
 
+  private static final ImmutableList<CelFunctionDecl> STATIC_FUNCTION_DECLS =
+      ImmutableList.of(
+          CEL_ATTRIBUTE_INT_FUNCTION_DECL,
+          CEL_ATTRIBUTE_UINT_FUNCTION_DECL,
+          CEL_ATTRIBUTE_DOUBLE_FUNCTION_DECL,
+          CEL_ATTRIBUTE_BOOL_FUNCTION_DECL,
+          CEL_ATTRIBUTE_STRING_FUNCTION_DECL,
+          CEL_ATTRIBUTE_BYTES_FUNCTION_DECL,
+          CEL_ATTRIBUTE_DURATION_FUNCTION_DECL,
+          CEL_ATTRIBUTE_TIMESTAMP_FUNCTION_DECL,
+          CEL_ATTRIBUTE_LIST_FUNCTION_DECL,
+          CEL_ATTRIBUTE_MAP_FUNCTION_DECL,
+          CEL_HAS_FIELD_FUNCTION_DECL);
+
   @VisibleForTesting
   static final Extension SELECT_OPTIMIZATION_AST_EXTENSION_TAG =
       Extension.create("select_optimization", Version.of(1L, 0L), Component.COMPONENT_RUNTIME);
@@ -168,7 +277,7 @@ public static SelectOptimizer newInstance(Iterable<FileDescriptor> fileDescripto
   /** Returns a new select optimizer configured with the provided options and file descriptors. */
   public static SelectOptimizer newInstance(
       SelectOptimizerOptions options, FileDescriptor... fileDescriptors) {
-    return newInstance(options, Arrays.asList(checkNotNull(fileDescriptors)));
+    return newInstance(checkNotNull(options), Arrays.asList(checkNotNull(fileDescriptors)));
   }
 
   /** Returns a new select optimizer configured with the provided options and file descriptors. */
@@ -199,28 +308,33 @@ public OptimizationResult optimize(CelAbstractSyntaxTree ast, Cel cel) {
     MonotonicIdGenerator idGenerator =
         CelExprIdGeneratorFactory.newMonotonicIdGenerator(navAst.getRoot().maxId());
 
+    LinkedHashMap<String, CelFunctionDecl> dynamicMessageFunctionDecls = new LinkedHashMap<>();
     int iterationCount = 0;
     for (CelNavigableMutableExpr topNode : topOfChainSelects) {
       if (++iterationCount > options.iterationLimit()) {
         throw new IllegalStateException("Max iteration count reached.");
       }
-      rewriteSelectChain(astToModify, navAst, topNode, idGenerator);
+      rewriteSelectChain(astToModify, navAst, topNode, idGenerator, dynamicMessageFunctionDecls);
     }
 
     astToModify = astMutator.renumberIdsConsecutively(astToModify);
     CelAbstractSyntaxTree optimizedAst = tagAstExtension(astToModify.toParsedAst());
 
-    return OptimizationResult.create(
-        optimizedAst,
-        ImmutableList.of(),
-        ImmutableList.of(CEL_ATTRIBUTE_FUNCTION_DECL, CEL_HAS_FIELD_FUNCTION_DECL));
+    ImmutableList.Builder<CelFunctionDecl> allFunctionDecls =
+        ImmutableList.builderWithExpectedSize(
+            STATIC_FUNCTION_DECLS.size() + dynamicMessageFunctionDecls.size());
+    allFunctionDecls.addAll(STATIC_FUNCTION_DECLS);
+    allFunctionDecls.addAll(dynamicMessageFunctionDecls.values());
+
+    return OptimizationResult.create(optimizedAst, ImmutableList.of(), allFunctionDecls.build());
   }
 
   private void rewriteSelectChain(
       CelMutableAst astToModify,
       CelNavigableMutableAst navAst,
       CelNavigableMutableExpr topNode,
-      MonotonicIdGenerator idGenerator) {
+      MonotonicIdGenerator idGenerator,
+      Map<String, CelFunctionDecl> dynamicMessageFunctionDecls) {
     boolean isHasField = topNode.expr().select().testOnly();
     astToModify.source().getMacroCalls().remove(topNode.expr().id());
 
@@ -235,11 +349,11 @@ private void rewriteSelectChain(
     CelMutableExpr currentExpr = topNode.expr().select().operand();
     while (currentExpr.getKind() == Kind.SELECT) {
       CelMutableSelect select = currentExpr.select();
-      FieldDescriptor field = getOptimizableFieldForExpr(navAst, select).orElse(null);
-      if (field == null) {
+      Optional<FieldDescriptor> field = getOptimizableFieldForExpr(navAst, select);
+      if (!field.isPresent()) {
         break;
       }
-      fields.add(field);
+      fields.add(field.get());
       currentExpr = select.operand();
     }
 
@@ -295,10 +409,77 @@ private void rewriteSelectChain(
 
     CelMutableExpr qualifiersExpr =
         CelMutableExpr.ofList(idGenerator.nextExprId(), CelMutableList.create(qualifierLists));
-    String functionName = isHasField ? CEL_HAS_FIELD_FUNCTION_NAME : CEL_ATTRIBUTE_FUNCTION_NAME;
+    String functionName =
+        isHasField ? CEL_HAS_FIELD_FUNCTION_NAME : resolveAttributeFunctionName(topField);
+    if (functionName.startsWith(CEL_ATTRIBUTE_MESSAGE_FUNCTION_PREFIX)) {
+      String messageFullName = topField.getMessageType().getFullName();
+      dynamicMessageFunctionDecls.computeIfAbsent(
+          functionName, fnName -> newAttributeMessageFunctionDeclaration(messageFullName));
+    }
     topNode.expr().setCall(CelMutableCall.create(functionName, currentExpr, qualifiersExpr));
   }
 
+  private static String resolveAttributeFunctionName(FieldDescriptor leafField) {
+    if (leafField.isMapField()) {
+      return CEL_ATTRIBUTE_MAP_FUNCTION_NAME;
+    }
+    if (leafField.isRepeated()) {
+      return CEL_ATTRIBUTE_LIST_FUNCTION_NAME;
+    }
+    switch (leafField.getType()) {
+      case INT32:
+      case INT64:
+      case SINT32:
+      case SINT64:
+      case SFIXED32:
+      case SFIXED64:
+      case ENUM:
+        return CEL_ATTRIBUTE_INT_FUNCTION_NAME;
+      case UINT32:
+      case UINT64:
+      case FIXED32:
+      case FIXED64:
+        return CEL_ATTRIBUTE_UINT_FUNCTION_NAME;
+      case DOUBLE:
+      case FLOAT:
+        return CEL_ATTRIBUTE_DOUBLE_FUNCTION_NAME;
+      case BOOL:
+        return CEL_ATTRIBUTE_BOOL_FUNCTION_NAME;
+      case STRING:
+        return CEL_ATTRIBUTE_STRING_FUNCTION_NAME;
+      case BYTES:
+        return CEL_ATTRIBUTE_BYTES_FUNCTION_NAME;
+      case MESSAGE:
+        String messageFullName = leafField.getMessageType().getFullName();
+        if (messageFullName.equals(CelTypes.DURATION_MESSAGE)) {
+          return CEL_ATTRIBUTE_DURATION_FUNCTION_NAME;
+        }
+        if (messageFullName.equals(CelTypes.TIMESTAMP_MESSAGE)) {
+          return CEL_ATTRIBUTE_TIMESTAMP_FUNCTION_NAME;
+        }
+        return getAttributeMessageFunctionName(messageFullName);
+      default:
+        throw new IllegalArgumentException(
+            "Unsupported protobuf field type: " + leafField.getType());
+    }
+  }
+
+  private static String getAttributeMessageFunctionName(String messageFullName) {
+    checkNotNull(messageFullName);
+    return CEL_ATTRIBUTE_MESSAGE_FUNCTION_PREFIX + messageFullName;
+  }
+
+  private static CelFunctionDecl newAttributeMessageFunctionDeclaration(String messageFullName) {
+    checkNotNull(messageFullName);
+    return CelFunctionDecl.newFunctionDeclaration(
+        getAttributeMessageFunctionName(messageFullName),
+        CelOverloadDecl.newGlobalOverload(
+            "cel_attribute_message_" + messageFullName.replace('.', '_'),
+            StructTypeReference.create(messageFullName),
+            SimpleType.DYN,
+            ListType.create(SimpleType.DYN)));
+  }
+
   private static long resolveTypeCode(FieldDescriptor field) {
     if (field.isMapField()) {
       return CEL_MAP_TYPE_CODE;
@@ -414,13 +595,6 @@ private static CelAbstractSyntaxTree tagAstExtension(CelAbstractSyntaxTree ast)
     return CelAbstractSyntaxTree.newParsedAst(ast.getExpr(), celSourceBuilder.build());
   }
 
-  private SelectOptimizer(
-      SelectOptimizerOptions options, Iterable<FileDescriptor> fileDescriptors) {
-    this.options = checkNotNull(options);
-    this.astMutator = AstMutator.newInstance(options.iterationLimit());
-    this.descriptorPool = newDescriptorPool(options, checkNotNull(fileDescriptors));
-  }
-
   private static CelDescriptorPool newDescriptorPool(
       SelectOptimizerOptions options, Iterable<FileDescriptor> fileDescriptors) {
     CelDescriptors celDescriptors =
@@ -432,6 +606,13 @@ private static CelDescriptorPool newDescriptorPool(
     return CombinedDescriptorPool.create(descriptorPools.build());
   }
 
+  private SelectOptimizer(
+      SelectOptimizerOptions options, Iterable<FileDescriptor> fileDescriptors) {
+    this.options = checkNotNull(options);
+    this.astMutator = AstMutator.newInstance(options.iterationLimit());
+    this.descriptorPool = newDescriptorPool(options, checkNotNull(fileDescriptors));
+  }
+
   /** Options configuring the behavior of {@link SelectOptimizer}. */
   @AutoValue
   public abstract static class SelectOptimizerOptions {
diff --git a/optimizer/src/test/java/dev/cel/optimizer/optimizers/BUILD.bazel b/optimizer/src/test/java/dev/cel/optimizer/optimizers/BUILD.bazel
index 787012466..1fd34709a 100644
--- a/optimizer/src/test/java/dev/cel/optimizer/optimizers/BUILD.bazel
+++ b/optimizer/src/test/java/dev/cel/optimizer/optimizers/BUILD.bazel
@@ -26,6 +26,7 @@ java_library(
         "//extensions:optional_library",
         #         "//java/com/google/testing/testsize:annotations",
         "//optimizer",
+        "//optimizer:ast_optimizer",
         "//optimizer:optimization_exception",
         "//optimizer:optimizer_builder",
         "//optimizer/optimizers:common_subexpression_elimination",
diff --git a/optimizer/src/test/java/dev/cel/optimizer/optimizers/SelectOptimizerTest.java b/optimizer/src/test/java/dev/cel/optimizer/optimizers/SelectOptimizerTest.java
index 7740319fe..0494aa209 100644
--- a/optimizer/src/test/java/dev/cel/optimizer/optimizers/SelectOptimizerTest.java
+++ b/optimizer/src/test/java/dev/cel/optimizer/optimizers/SelectOptimizerTest.java
@@ -17,6 +17,7 @@
 import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.common.collect.ImmutableList.toImmutableList;
 import static com.google.common.truth.Truth.assertThat;
+import static com.google.common.truth.Truth.assertWithMessage;
 import static com.google.common.truth.extensions.proto.ProtoTruth.assertThat;
 import static org.junit.Assert.assertThrows;
 
@@ -34,15 +35,19 @@
 import dev.cel.common.CelFunctionDecl;
 import dev.cel.common.CelMutableAst;
 import dev.cel.common.CelOptions;
+import dev.cel.common.CelOverloadDecl;
 import dev.cel.common.CelProtoAbstractSyntaxTree;
 import dev.cel.common.CelValidationException;
+import dev.cel.common.ast.CelReference;
 import dev.cel.common.navigation.CelNavigableMutableAst;
+import dev.cel.common.types.ListType;
 import dev.cel.common.types.MapType;
 import dev.cel.common.types.SimpleType;
 import dev.cel.common.types.StructTypeReference;
 import dev.cel.expr.conformance.proto2.NestedTestAllTypes;
 import dev.cel.expr.conformance.proto2.TestAllTypesProto;
 import dev.cel.expr.conformance.proto3.TestAllTypes;
+import dev.cel.optimizer.CelAstOptimizer.OptimizationResult;
 import dev.cel.optimizer.CelOptimizer;
 import dev.cel.optimizer.CelOptimizerFactory;
 import dev.cel.optimizer.optimizers.SelectOptimizer.SelectOptimizerOptions;
@@ -119,27 +124,31 @@ private static Cel setupEnv(CelBuilder celBuilder) {
   private enum RewriteTestCase {
     // === Selection & Traversal ===
     PROTO3_SINGLE_FIELD_SELECT(
-        "msg.single_int64", "cel.@attribute(msg, [[2, \"single_int64\", 3, 0]])"),
+        "msg.single_int64", "cel.@attributeInt(msg, [[2, \"single_int64\", 3, 0]])"),
     PROTO3_SINGLE_MESSAGE_FIELD_SELECT(
-        "msg.single_nested_message", "cel.@attribute(msg, [[21, \"single_nested_message\", 11]])"),
+        "msg.single_nested_message",
+        "cel.@attributeMessage:cel.expr.conformance.proto3.TestAllTypes.NestedMessage(msg, [[21,"
+            + " \"single_nested_message\", 11]])"),
     PROTO3_CHAINED_FIELD_SELECT(
         "msg.single_nested_message.bb",
-        "cel.@attribute(msg, [[21, \"single_nested_message\", 11], [1, \"bb\", 5, 0]])"),
+        "cel.@attributeInt(msg, [[21, \"single_nested_message\", 11], [1, \"bb\", 5, 0]])"),
     PROTO2_SINGLE_MESSAGE_FIELD_SELECT(
         "proto2_msg.single_nested_message",
-        "cel.@attribute(proto2_msg, [[21, \"single_nested_message\", 11]])"),
+        "cel.@attributeMessage:cel.expr.conformance.proto2.TestAllTypes.NestedMessage(proto2_msg,"
+            + " [[21, \"single_nested_message\", 11]])"),
     PROTO2_CHAINED_FIELD_SELECT(
         "proto2_msg.single_nested_message.bb",
-        "cel.@attribute(proto2_msg, [[21, \"single_nested_message\", 11], [1, \"bb\", 5, 0]])"),
+        "cel.@attributeInt(proto2_msg, [[21, \"single_nested_message\", 11], [1, \"bb\", 5, 0]])"),
     PROTO2_TRIPLE_CHAINED_FIELD_SELECT(
         "nested_msg.child.payload.single_int64",
-        "cel.@attribute(nested_msg, "
+        "cel.@attributeInt(nested_msg, "
             + "[[1, \"child\", 11], "
             + "[2, \"payload\", 11], "
             + "[2, \"single_int64\", 3, -64]])"),
     PROTO2_CHAINED_MESSAGE_FIELD_SELECT(
         "nested_msg.child.payload",
-        "cel.@attribute(nested_msg, [[1, \"child\", 11], [2, \"payload\", 11]])"),
+        "cel.@attributeMessage:cel.expr.conformance.proto2.TestAllTypes(nested_msg, [[1,"
+            + " \"child\", 11], [2, \"payload\", 11]])"),
 
     // === Presence Tests: Proto2 (Explicit Presence) vs Proto3 (Implicit/Explicit Presence) ===
     // In proto2, scalar fields have explicit presence (has-bit).
@@ -178,102 +187,134 @@ private enum RewriteTestCase {
     // === Default Value Divergence: Proto2 Custom Defaults vs Proto3 Zero Defaults ===
     // Int32: proto2 has custom default -32, proto3 has 0
     PROTO2_CUSTOM_INT32(
-        "proto2_msg.single_int32", "cel.@attribute(proto2_msg, [[1, \"single_int32\", 5, -32]])"),
-    PROTO3_ZERO_INT32("msg.single_int32", "cel.@attribute(msg, [[1, \"single_int32\", 5, 0]])"),
+        "proto2_msg.single_int32",
+        "cel.@attributeInt(proto2_msg, [[1, \"single_int32\", 5, -32]])"),
+    PROTO3_ZERO_INT32("msg.single_int32", "cel.@attributeInt(msg, [[1, \"single_int32\", 5, 0]])"),
 
     // Int64: proto2 has custom default -64, proto3 has 0
     PROTO2_CUSTOM_INT64(
-        "proto2_msg.single_int64", "cel.@attribute(proto2_msg, [[2, \"single_int64\", 3, -64]])"),
-    PROTO3_ZERO_INT64("msg.single_int64", "cel.@attribute(msg, [[2, \"single_int64\", 3, 0]])"),
+        "proto2_msg.single_int64",
+        "cel.@attributeInt(proto2_msg, [[2, \"single_int64\", 3, -64]])"),
+    PROTO3_ZERO_INT64("msg.single_int64", "cel.@attributeInt(msg, [[2, \"single_int64\", 3, 0]])"),
 
     // Uint32: proto2 has custom default 32, proto3 has 0
     PROTO2_CUSTOM_UINT32(
         "proto2_msg.single_uint32",
-        "cel.@attribute(proto2_msg, [[3, \"single_uint32\", 13, 32u]])"),
+        "cel.@attributeUint(proto2_msg, [[3, \"single_uint32\", 13, 32u]])"),
     PROTO3_ZERO_UINT32(
-        "msg.single_uint32", "cel.@attribute(msg, [[3, \"single_uint32\", 13, 0u]])"),
+        "msg.single_uint32", "cel.@attributeUint(msg, [[3, \"single_uint32\", 13, 0u]])"),
 
     // Uint64: proto2 has custom default 64, proto3 has 0
     PROTO2_CUSTOM_UINT64(
-        "proto2_msg.single_uint64", "cel.@attribute(proto2_msg, [[4, \"single_uint64\", 4, 64u]])"),
-    PROTO3_ZERO_UINT64("msg.single_uint64", "cel.@attribute(msg, [[4, \"single_uint64\", 4, 0u]])"),
+        "proto2_msg.single_uint64",
+        "cel.@attributeUint(proto2_msg, [[4, \"single_uint64\", 4, 64u]])"),
+    PROTO3_ZERO_UINT64(
+        "msg.single_uint64", "cel.@attributeUint(msg, [[4, \"single_uint64\", 4, 0u]])"),
 
     // String: proto2 has custom default "empty", proto3 has ""
     PROTO2_CUSTOM_STRING(
         "proto2_msg.single_string",
-        "cel.@attribute(proto2_msg, [[14, \"single_string\", 9, \"empty\"]])"),
+        "cel.@attributeString(proto2_msg, [[14, \"single_string\", 9, \"empty\"]])"),
     PROTO3_ZERO_STRING(
-        "msg.single_string", "cel.@attribute(msg, [[14, \"single_string\", 9, \"\"]])"),
+        "msg.single_string", "cel.@attributeString(msg, [[14, \"single_string\", 9, \"\"]])"),
 
     // Bool: proto2 has custom default true, proto3 has false
     PROTO2_CUSTOM_BOOL(
-        "proto2_msg.single_bool", "cel.@attribute(proto2_msg, [[13, \"single_bool\", 8, true]])"),
-    PROTO3_ZERO_BOOL("msg.single_bool", "cel.@attribute(msg, [[13, \"single_bool\", 8, false]])"),
+        "proto2_msg.single_bool",
+        "cel.@attributeBool(proto2_msg, [[13, \"single_bool\", 8, true]])"),
+    PROTO3_ZERO_BOOL(
+        "msg.single_bool", "cel.@attributeBool(msg, [[13, \"single_bool\", 8, false]])"),
 
     // Float: proto2 has custom default 3.0, proto3 has 0.0
     PROTO2_CUSTOM_FLOAT(
-        "proto2_msg.single_float", "cel.@attribute(proto2_msg, [[11, \"single_float\", 2, 3.0]])"),
-    PROTO3_ZERO_FLOAT("msg.single_float", "cel.@attribute(msg, [[11, \"single_float\", 2, 0.0]])"),
+        "proto2_msg.single_float",
+        "cel.@attributeDouble(proto2_msg, [[11, \"single_float\", 2, 3.0]])"),
+    PROTO3_ZERO_FLOAT(
+        "msg.single_float", "cel.@attributeDouble(msg, [[11, \"single_float\", 2, 0.0]])"),
 
     // Double: proto2 has custom default 6.4, proto3 has 0.0
     PROTO2_CUSTOM_DOUBLE(
         "proto2_msg.single_double",
-        "cel.@attribute(proto2_msg, [[12, \"single_double\", 1, 6.4]])"),
+        "cel.@attributeDouble(proto2_msg, [[12, \"single_double\", 1, 6.4]])"),
     PROTO3_ZERO_DOUBLE(
-        "msg.single_double", "cel.@attribute(msg, [[12, \"single_double\", 1, 0.0]])"),
+        "msg.single_double", "cel.@attributeDouble(msg, [[12, \"single_double\", 1, 0.0]])"),
 
     // Bytes: proto2 has custom default "none", proto3 has ""
     PROTO2_CUSTOM_BYTES(
         "proto2_msg.single_bytes",
-        "cel.@attribute(proto2_msg, [[15, \"single_bytes\", 12, b\"\\156\\157\\156\\145\"]])"),
+        "cel.@attributeBytes(proto2_msg, [[15, \"single_bytes\", 12, b\"\\156\\157\\156\\145\"]])"),
     PROTO3_ZERO_BYTES(
-        "msg.single_bytes", "cel.@attribute(msg, [[15, \"single_bytes\", 12, b\"\"]])"),
+        "msg.single_bytes", "cel.@attributeBytes(msg, [[15, \"single_bytes\", 12, b\"\"]])"),
 
     // Enum: proto2 has custom default 1 (BAR), proto3 has 0 (FOO)
     PROTO2_CUSTOM_ENUM(
         "proto2_msg.single_nested_enum",
-        "cel.@attribute(proto2_msg, [[22, \"single_nested_enum\", 14, 1]])"),
+        "cel.@attributeInt(proto2_msg, [[22, \"single_nested_enum\", 14, 1]])"),
     PROTO3_ZERO_ENUM(
-        "msg.single_nested_enum", "cel.@attribute(msg, [[22, \"single_nested_enum\", 14, 0]])"),
-
-    // Fixed / sfixed fields
+        "msg.single_nested_enum", "cel.@attributeInt(msg, [[22, \"single_nested_enum\", 14, 0]])"),
+
+    // Sint / fixed / sfixed fields
+    PROTO3_SINT32("msg.single_sint32", "cel.@attributeInt(msg, [[5, \"single_sint32\", 17, 0]])"),
+    PROTO3_SINT64("msg.single_sint64", "cel.@attributeInt(msg, [[6, \"single_sint64\", 18, 0]])"),
+    PROTO3_FIXED32(
+        "msg.single_fixed32", "cel.@attributeUint(msg, [[7, \"single_fixed32\", 7, 0u]])"),
+    PROTO3_FIXED64(
+        "msg.single_fixed64", "cel.@attributeUint(msg, [[8, \"single_fixed64\", 6, 0u]])"),
     PROTO3_SFIXED32(
-        "msg.single_sfixed32", "cel.@attribute(msg, [[9, \"single_sfixed32\", 15, 0]])"),
+        "msg.single_sfixed32", "cel.@attributeInt(msg, [[9, \"single_sfixed32\", 15, 0]])"),
     PROTO3_SFIXED64(
-        "msg.single_sfixed64", "cel.@attribute(msg, [[10, \"single_sfixed64\", 16, 0]])"),
+        "msg.single_sfixed64", "cel.@attributeInt(msg, [[10, \"single_sfixed64\", 16, 0]])"),
+    PROTO2_SINT32(
+        "proto2_msg.single_sint32",
+        "cel.@attributeInt(proto2_msg, [[5, \"single_sint32\", 17, 0]])"),
+    PROTO2_SINT64(
+        "proto2_msg.single_sint64",
+        "cel.@attributeInt(proto2_msg, [[6, \"single_sint64\", 18, 0]])"),
+    PROTO2_FIXED32(
+        "proto2_msg.single_fixed32",
+        "cel.@attributeUint(proto2_msg, [[7, \"single_fixed32\", 7, 0u]])"),
+    PROTO2_FIXED64(
+        "proto2_msg.single_fixed64",
+        "cel.@attributeUint(proto2_msg, [[8, \"single_fixed64\", 6, 0u]])"),
+    PROTO2_SFIXED32(
+        "proto2_msg.single_sfixed32",
+        "cel.@attributeInt(proto2_msg, [[9, \"single_sfixed32\", 15, 0]])"),
+    PROTO2_SFIXED64(
+        "proto2_msg.single_sfixed64",
+        "cel.@attributeInt(proto2_msg, [[10, \"single_sfixed64\", 16, 0]])"),
 
     // Repeated fields: empty list default
     PROTO2_REPEATED_PRIMITIVE(
         "proto2_msg.repeated_int64",
-        "cel.@attribute(proto2_msg, [[32, \"repeated_int64\", 3, []]])"),
+        "cel.@attributeList(proto2_msg, [[32, \"repeated_int64\", 3, []]])"),
     PROTO3_REPEATED_PRIMITIVE(
-        "msg.repeated_int64", "cel.@attribute(msg, [[32, \"repeated_int64\", 3, []]])"),
+        "msg.repeated_int64", "cel.@attributeList(msg, [[32, \"repeated_int64\", 3, []]])"),
     PROTO3_REPEATED_MESSAGE(
         "msg.repeated_nested_message",
-        "cel.@attribute(msg, [[51, \"repeated_nested_message\", 11, []]])"),
+        "cel.@attributeList(msg, [[51, \"repeated_nested_message\", 11, []]])"),
 
     // Well-known types
     PROTO3_TIMESTAMP(
         "msg.single_timestamp",
-        "cel.@attribute(msg, [[102, \"single_timestamp\", 11, timestamp(0)]])"),
+        "cel.@attributeTimestamp(msg, [[102, \"single_timestamp\", 11, timestamp(0)]])"),
     PROTO3_DURATION(
         "msg.single_duration",
-        "cel.@attribute(msg, [[101, \"single_duration\", 11, duration(\"0s\")]])"),
+        "cel.@attributeDuration(msg, [[101, \"single_duration\", 11, duration(\"0s\")]])"),
 
     // Map selects
     MAP_FIELD_INDEXING(
         "msg.map_int64_message[1].bb",
-        "cel.@attribute("
-            + "cel.@attribute(msg, [[95, \"map_int64_message\", 20, {}]])[1], "
+        "cel.@attributeInt("
+            + "cel.@attributeMap(msg, [[95, \"map_int64_message\", 20, {}]])[1], "
             + "[[1, \"bb\", 5, 0]])"),
     MAP_FIELD_SELECT_CHAIN_STOPS_AT_MAP_BOUNDARY(
         "map_var_msg.key.single_nested_message.bb",
-        "cel.@attribute(map_var_msg.key, "
+        "cel.@attributeInt(map_var_msg.key, "
             + "[[21, \"single_nested_message\", 11], "
             + "[1, \"bb\", 5, 0]])"),
     MAP_FIELD_SELECT_STOPS_AT_MAP_BOUNDARY(
         "map_var_msg.key.single_int64",
-        "cel.@attribute(map_var_msg.key, [[2, \"single_int64\", 3, 0]])"),
+        "cel.@attributeInt(map_var_msg.key, [[2, \"single_int64\", 3, 0]])"),
     MAP_FIELD_HAS_STOPS_AT_MAP_BOUNDARY(
         "has(map_var_msg.key.single_nested_message)",
         "cel.@hasField(map_var_msg.key, [[21, \"single_nested_message\"]])"),
@@ -282,18 +323,18 @@ private enum RewriteTestCase {
         "cel.@hasField(map_var_msg.key, [[21, \"single_nested_message\"], [1, \"bb\"]])"),
     PROTO_MAP_FIELD_SELECT_STOPS_AT_MAP_BOUNDARY(
         "msg.map_string_message.key.bb",
-        "cel.@attribute("
-            + "cel.@attribute(msg, [[227, \"map_string_message\", 20, {}]]).key, "
+        "cel.@attributeInt("
+            + "cel.@attributeMap(msg, [[227, \"map_string_message\", 20, {}]]).key, "
             + "[[1, \"bb\", 5, 0]])"),
     PROTO_MAP_FIELD_HAS_STOPS_AT_MAP_BOUNDARY(
         "has(msg.map_string_message.key.bb)",
         "cel.@hasField("
-            + "cel.@attribute(msg, [[227, \"map_string_message\", 20, {}]]).key, "
+            + "cel.@attributeMap(msg, [[227, \"map_string_message\", 20, {}]]).key, "
             + "[[1, \"bb\"]])"),
 
     MIXED_BOOLEAN_EXPRESSION(
         "msg.single_int64 > 0 && has(msg.single_nested_message)",
-        "cel.@attribute(msg, [[2, \"single_int64\", 3, 0]]) > 0 "
+        "cel.@attributeInt(msg, [[2, \"single_int64\", 3, 0]]) > 0 "
             + "&& cel.@hasField(msg, [[21, \"single_nested_message\"]])");
 
     private final String expression;
@@ -376,7 +417,7 @@ public void optimize_withFileDescriptors_success() throws Exception {
     CelAbstractSyntaxTree optimizedAst = optimizer.optimize(ast);
 
     assertThat(CEL_UNPARSER.unparse(optimizedAst))
-        .isEqualTo("cel.@attribute(msg, [[2, \"single_int64\", 3, 0]])");
+        .isEqualTo("cel.@attributeInt(msg, [[2, \"single_int64\", 3, 0]])");
   }
 
   @Test
@@ -394,7 +435,7 @@ public void optimize_withFileDescriptorsIterable_success() throws Exception {
     CelAbstractSyntaxTree optimizedAst = optimizer.optimize(ast);
 
     assertThat(CEL_UNPARSER.unparse(optimizedAst))
-        .isEqualTo("cel.@attribute(msg, [[2, \"single_int64\", 3, 0]])");
+        .isEqualTo("cel.@attributeInt(msg, [[2, \"single_int64\", 3, 0]])");
   }
 
   @Test
@@ -409,7 +450,7 @@ public void newInstance_withOptionsAndFileDescriptors_preservesAddedDescriptors(
     CelAbstractSyntaxTree optimizedAst = optimizer.optimize(ast, cel).optimizedAst();
 
     assertThat(CEL_UNPARSER.unparse(optimizedAst))
-        .isEqualTo("cel.@attribute(proto2_msg, [[2, \"single_int64\", 3, -64]])");
+        .isEqualTo("cel.@attributeInt(proto2_msg, [[2, \"single_int64\", 3, -64]])");
   }
 
   @Test
@@ -456,10 +497,10 @@ public void optimizeAndEvaluate_withAttributeFunctionBinding_evaluatesSuccessful
       throws Exception {
     Cel celWithBinding =
         cel.toCelBuilder()
-            .addFunctionDeclarations(SelectOptimizer.CEL_ATTRIBUTE_FUNCTION_DECL)
+            .addFunctionDeclarations(SelectOptimizer.CEL_ATTRIBUTE_INT_FUNCTION_DECL)
             .addFunctionBindings(
                 CelFunctionBinding.from(
-                    "cel_attribute_list", Object.class, List.class, (target, path) -> 42L))
+                    "cel_attribute_int_list", Object.class, List.class, (target, path) -> 42L))
             .build();
     CelOptimizer optimizer =
         CelOptimizerFactory.standardCelOptimizerBuilder(celWithBinding)
@@ -484,10 +525,10 @@ public void optimizeAndEvaluate_withChainedMessageSelect_unpacksTuplesSuccessful
       throws Exception {
     Cel celWithBinding =
         cel.toCelBuilder()
-            .addFunctionDeclarations(SelectOptimizer.CEL_ATTRIBUTE_FUNCTION_DECL)
+            .addFunctionDeclarations(SelectOptimizer.CEL_ATTRIBUTE_INT_FUNCTION_DECL)
             .addFunctionBindings(
                 CelFunctionBinding.from(
-                    "cel_attribute_list", Object.class, List.class, (target, path) -> path))
+                    "cel_attribute_int_list", Object.class, List.class, (target, path) -> path))
             .build();
     CelOptimizer optimizer =
         CelOptimizerFactory.standardCelOptimizerBuilder(celWithBinding)
@@ -542,10 +583,10 @@ public void optimizeAndEvaluate_withHasFieldFunctionBinding_evaluatesSuccessfull
   public void optimizeAndEvaluate_withSelectOnMapValue_evaluatesSuccessfully() throws Exception {
     Cel celWithBinding =
         cel.toCelBuilder()
-            .addFunctionDeclarations(SelectOptimizer.CEL_ATTRIBUTE_FUNCTION_DECL)
+            .addFunctionDeclarations(SelectOptimizer.CEL_ATTRIBUTE_INT_FUNCTION_DECL)
             .addFunctionBindings(
                 CelFunctionBinding.from(
-                    "cel_attribute_list", Object.class, List.class, (target, path) -> 42L))
+                    "cel_attribute_int_list", Object.class, List.class, (target, path) -> 42L))
             .build();
     CelOptimizer optimizer =
         CelOptimizerFactory.standardCelOptimizerBuilder(celWithBinding)
@@ -605,10 +646,10 @@ public void optimizeAndEvaluate_withHasOnMapValue_evaluatesSuccessfully() throws
   public void optimizeAndEvaluate_withMissingMapKey_throwsEvaluationException() throws Exception {
     Cel celWithBinding =
         cel.toCelBuilder()
-            .addFunctionDeclarations(SelectOptimizer.CEL_ATTRIBUTE_FUNCTION_DECL)
+            .addFunctionDeclarations(SelectOptimizer.CEL_ATTRIBUTE_INT_FUNCTION_DECL)
             .addFunctionBindings(
                 CelFunctionBinding.from(
-                    "cel_attribute_list", Object.class, List.class, (target, path) -> 42L))
+                    "cel_attribute_int_list", Object.class, List.class, (target, path) -> 42L))
             .build();
     CelOptimizer optimizer =
         CelOptimizerFactory.standardCelOptimizerBuilder(celWithBinding)
@@ -744,7 +785,7 @@ public void newInstance_fileDescriptorsVarargs_defaultOptions_success() throws E
     CelAbstractSyntaxTree optimizedAst = optimizer.optimize(ast, cel).optimizedAst();
 
     assertThat(CEL_UNPARSER.unparse(optimizedAst))
-        .isEqualTo("cel.@attribute(proto2_msg, [[2, \"single_int64\", 3, -64]])");
+        .isEqualTo("cel.@attributeInt(proto2_msg, [[2, \"single_int64\", 3, -64]])");
   }
 
   @Test
@@ -756,7 +797,7 @@ public void newInstance_fileDescriptorsIterable_defaultOptions_success() throws
     CelAbstractSyntaxTree optimizedAst = optimizer.optimize(ast, cel).optimizedAst();
 
     assertThat(CEL_UNPARSER.unparse(optimizedAst))
-        .isEqualTo("cel.@attribute(proto2_msg, [[2, \"single_int64\", 3, -64]])");
+        .isEqualTo("cel.@attributeInt(proto2_msg, [[2, \"single_int64\", 3, -64]])");
   }
 
   @Test
@@ -774,7 +815,7 @@ public void newInstance_fileDescriptorsIterable_defaultOptions_success() throws
     CelAbstractSyntaxTree proto3Optimized = optimizer.optimize(proto3Ast, cel).optimizedAst();
 
     assertThat(CEL_UNPARSER.unparse(proto2Optimized))
-        .isEqualTo("cel.@attribute(proto2_msg, [[2, \"single_int64\", 3, -64]])");
+        .isEqualTo("cel.@attributeInt(proto2_msg, [[2, \"single_int64\", 3, -64]])");
     assertThat(CEL_UNPARSER.unparse(proto3Optimized)).isEqualTo("msg.single_int64");
   }
 
@@ -794,19 +835,19 @@ public void newInstance_fileDescriptorsIterable_defaultOptions_success() throws
     CelAbstractSyntaxTree proto3Optimized = optimizer.optimize(proto3Ast, cel).optimizedAst();
 
     assertThat(CEL_UNPARSER.unparse(proto2Optimized))
-        .isEqualTo("cel.@attribute(proto2_msg, [[2, \"single_int64\", 3, -64]])");
+        .isEqualTo("cel.@attributeInt(proto2_msg, [[2, \"single_int64\", 3, -64]])");
     assertThat(CEL_UNPARSER.unparse(proto3Optimized)).isEqualTo("msg.single_int64");
   }
 
   private enum CompilerRejectionTestCase {
-    ATTRIBUTE_AT_SIGN(
-        SelectOptimizer.CEL_ATTRIBUTE_FUNCTION_DECL,
-        "cel.@attribute(msg, [])",
+    ATTRIBUTE_INT_AT_SIGN(
+        SelectOptimizer.CEL_ATTRIBUTE_INT_FUNCTION_DECL,
+        "cel.@attributeInt(msg, [])",
         "token recognition error at: '@'"),
-    ATTRIBUTE_OVERLOAD(
-        SelectOptimizer.CEL_ATTRIBUTE_FUNCTION_DECL,
-        "cel_attribute_list(msg, [])",
-        "undeclared reference to 'cel_attribute_list'"),
+    ATTRIBUTE_INT_OVERLOAD(
+        SelectOptimizer.CEL_ATTRIBUTE_INT_FUNCTION_DECL,
+        "cel_attribute_int_list(msg, [])",
+        "undeclared reference to 'cel_attribute_int_list'"),
     HAS_FIELD_AT_SIGN(
         SelectOptimizer.CEL_HAS_FIELD_FUNCTION_DECL,
         "cel.@hasField(msg, [])",
@@ -840,6 +881,220 @@ public void compile_sourceWithInternalFunctionCall_failsCompilation(
     assertThat(e).hasMessageThat().contains(testCase.expectedErrorMessage);
   }
 
+  @Test
+  public void optimize_binaryAddition_resolvesSingleOverload() throws Exception {
+    CelAbstractSyntaxTree ast = cel.compile("msg.single_int64 + msg.single_sfixed64").getAst();
+
+    CelAbstractSyntaxTree optimizedAst = celOptimizer.optimize(ast);
+
+    assertThat(CEL_UNPARSER.unparse(optimizedAst))
+        .isEqualTo(
+            "cel.@attributeInt(msg, [[2, \"single_int64\", 3, 0]]) + "
+                + "cel.@attributeInt(msg, [[10, \"single_sfixed64\", 16, 0]])");
+    assertThat(optimizedAst.isChecked()).isTrue();
+  }
+
+  @Test
+  public void optimize_stringConcatenation_resolvesSingleOverload() throws Exception {
+    CelAbstractSyntaxTree ast = cel.compile("msg.single_string + 'suffix'").getAst();
+
+    CelAbstractSyntaxTree optimizedAst = celOptimizer.optimize(ast);
+
+    assertThat(CEL_UNPARSER.unparse(optimizedAst))
+        .isEqualTo("cel.@attributeString(msg, [[14, \"single_string\", 9, \"\"]]) + \"suffix\"");
+    assertThat(optimizedAst.isChecked()).isTrue();
+  }
+
+  @Test
+  public void optimize_chainedSelectInBinaryExpression_resolvesSingleOverload() throws Exception {
+    CelAbstractSyntaxTree ast = cel.compile("msg.single_nested_message.bb + 1").getAst();
+
+    CelAbstractSyntaxTree optimizedAst = celOptimizer.optimize(ast);
+
+    assertThat(CEL_UNPARSER.unparse(optimizedAst))
+        .isEqualTo(
+            "cel.@attributeInt(msg, [[21, \"single_nested_message\", 11], [1, \"bb\", 5, 0]])"
+                + " + 1");
+    assertThat(optimizedAst.isChecked()).isTrue();
+  }
+
+  private enum OverloadResolutionTestCase {
+    INT_ADDITION("msg.single_int64 + msg.single_sfixed64", "add_int64"),
+    UINT_ADDITION("msg.single_uint64 + msg.single_fixed64", "add_uint64"),
+    DOUBLE_ADDITION("msg.single_double + msg.single_float", "add_double"),
+    STRING_ADDITION("msg.single_string + 'suffix'", "add_string"),
+    BYTES_ADDITION("msg.single_bytes + b'suffix'", "add_bytes"),
+    TIMESTAMP_DURATION_ADDITION(
+        "msg.single_timestamp + msg.single_duration", "add_timestamp_duration"),
+    LOGICAL_AND("msg.single_bool && true", "logical_and");
+
+    private final String expression;
+    private final String expectedOverloadId;
+
+    OverloadResolutionTestCase(String expression, String expectedOverloadId) {
+      this.expression = expression;
+      this.expectedOverloadId = expectedOverloadId;
+    }
+  }
+
+  @Test
+  public void optimize_binaryOperation_hasUnambiguousOverloadReference(
+      @TestParameter OverloadResolutionTestCase testCase) throws Exception {
+    CelAbstractSyntaxTree ast = cel.compile(testCase.expression).getAst();
+
+    CelAbstractSyntaxTree optimizedAst = celOptimizer.optimize(ast);
+
+    // Root node is the binary call.
+    assertThat(
+            optimizedAst.getReference(optimizedAst.getExpr().id()).map(CelReference::overloadIds))
+        .hasValue(ImmutableList.of(testCase.expectedOverloadId));
+  }
+
+  @Test
+  public void optimize_binaryOperation_referenceMapContainsOnlySingularOverload(
+      @TestParameter OverloadResolutionTestCase testCase) throws Exception {
+    CelAbstractSyntaxTree ast = cel.compile(testCase.expression).getAst();
+
+    CelAbstractSyntaxTree optimizedAst = celOptimizer.optimize(ast);
+
+    // Verify all call references in the AST have exactly one resolved overload, never a list of
+    // candidates.
+    ImmutableList<CelReference> callReferences =
+        optimizedAst.getReferenceMap().values().stream()
+            .filter(ref -> !ref.overloadIds().isEmpty())
+            .collect(toImmutableList());
+    assertThat(callReferences).isNotEmpty();
+    for (CelReference ref : callReferences) {
+      assertWithMessage("Call reference %s must have exactly 1 resolved overload", ref)
+          .that(ref.overloadIds())
+          .hasSize(1);
+    }
+  }
+
+  @Test
+  public void optimize_pipelineWithDownstreamOptimizer_generatesSingularOverload()
+      throws Exception {
+    CelOptimizer chainedOptimizer =
+        CelOptimizerFactory.standardCelOptimizerBuilder(cel)
+            .addAstOptimizers(
+                SelectOptimizer.newInstance(TestAllTypes.getDescriptor().getFile()),
+                ConstantFoldingOptimizer.getInstance())
+            .build();
+    CelAbstractSyntaxTree ast = cel.compile("msg.single_int64 + (1 + 2)").getAst();
+
+    CelAbstractSyntaxTree optimizedAst = chainedOptimizer.optimize(ast);
+
+    assertThat(CEL_UNPARSER.unparse(optimizedAst))
+        .isEqualTo("cel.@attributeInt(msg, [[2, \"single_int64\", 3, 0]]) + 3");
+    assertThat(
+            optimizedAst.getReference(optimizedAst.getExpr().id()).map(CelReference::overloadIds))
+        .hasValue(ImmutableList.of("add_int64"));
+  }
+
+  @Test
+  public void optimize_messageEquality_typeChecksSuccessfully() throws Exception {
+    CelAbstractSyntaxTree ast =
+        cel.compile("msg.single_nested_message == msg.single_nested_message").getAst();
+
+    CelAbstractSyntaxTree optimizedAst = celOptimizer.optimize(ast);
+
+    assertThat(CEL_UNPARSER.unparse(optimizedAst))
+        .isEqualTo(
+            "cel.@attributeMessage:cel.expr.conformance.proto3.TestAllTypes.NestedMessage(msg,"
+                + " [[21, \"single_nested_message\", 11]]) == "
+                + "cel.@attributeMessage:cel.expr.conformance.proto3.TestAllTypes.NestedMessage(msg,"
+                + " [[21, \"single_nested_message\", 11]])");
+    assertThat(optimizedAst.isChecked()).isTrue();
+  }
+
+  @Test
+  public void optimize_messagePassedToCustomFunction_typeChecksSuccessfully() throws Exception {
+    Cel celWithFn =
+        cel.toCelBuilder()
+            .addFunctionDeclarations(
+                CelFunctionDecl.newFunctionDeclaration(
+                    "takeNested",
+                    CelOverloadDecl.newGlobalOverload(
+                        "take_nested",
+                        SimpleType.BOOL,
+                        StructTypeReference.create(
+                            TestAllTypes.NestedMessage.getDescriptor().getFullName()))))
+            .build();
+    CelOptimizer optimizer =
+        CelOptimizerFactory.standardCelOptimizerBuilder(celWithFn)
+            .addAstOptimizers(SelectOptimizer.newInstance(TestAllTypes.getDescriptor().getFile()))
+            .build();
+    CelAbstractSyntaxTree ast = celWithFn.compile("takeNested(msg.single_nested_message)").getAst();
+
+    CelAbstractSyntaxTree optimizedAst = optimizer.optimize(ast);
+
+    assertThat(CEL_UNPARSER.unparse(optimizedAst))
+        .isEqualTo(
+            "takeNested(cel.@attributeMessage:cel.expr.conformance.proto3.TestAllTypes.NestedMessage(msg,"
+                + " [[21, \"single_nested_message\", 11]]))");
+    assertThat(optimizedAst.isChecked()).isTrue();
+  }
+
+  @Test
+  public void optimize_overloadedMessageFunction_resolvesSingleOverload() throws Exception {
+    Cel celWithFn =
+        cel.toCelBuilder()
+            .addFunctionDeclarations(
+                CelFunctionDecl.newFunctionDeclaration(
+                    "processMsg",
+                    CelOverloadDecl.newGlobalOverload(
+                        "process_nested",
+                        SimpleType.BOOL,
+                        StructTypeReference.create(
+                            TestAllTypes.NestedMessage.getDescriptor().getFullName())),
+                    CelOverloadDecl.newGlobalOverload(
+                        "process_all_types",
+                        SimpleType.BOOL,
+                        StructTypeReference.create(TestAllTypes.getDescriptor().getFullName()))))
+            .build();
+    CelOptimizer optimizer =
+        CelOptimizerFactory.standardCelOptimizerBuilder(celWithFn)
+            .addAstOptimizers(SelectOptimizer.newInstance(TestAllTypes.getDescriptor().getFile()))
+            .build();
+    CelAbstractSyntaxTree ast = celWithFn.compile("processMsg(msg.single_nested_message)").getAst();
+
+    CelAbstractSyntaxTree optimizedAst = optimizer.optimize(ast);
+
+    assertThat(
+            optimizedAst.getReference(optimizedAst.getExpr().id()).map(CelReference::overloadIds))
+        .hasValue(ImmutableList.of("process_nested"));
+    assertThat(optimizedAst.getResultType()).isEqualTo(SimpleType.BOOL);
+  }
+
+  @Test
+  public void optimize_newFunctionDecls_containsDynamicMessageFunctionDeclAndDeduplicates()
+      throws Exception {
+    SelectOptimizer optimizer = SelectOptimizer.newInstance(TestAllTypes.getDescriptor().getFile());
+    CelAbstractSyntaxTree ast =
+        cel.compile("msg.single_nested_message == msg.single_nested_message").getAst();
+
+    OptimizationResult result = optimizer.optimize(ast, cel);
+
+    String expectedFunctionName =
+        "cel.@attributeMessage:" + TestAllTypes.NestedMessage.getDescriptor().getFullName();
+    ImmutableList<CelFunctionDecl> dynamicDecls =
+        result.newFunctionDecls().stream()
+            .filter(decl -> decl.name().equals(expectedFunctionName))
+            .collect(toImmutableList());
+    CelFunctionDecl expectedDecl =
+        CelFunctionDecl.newFunctionDeclaration(
+            expectedFunctionName,
+            CelOverloadDecl.newGlobalOverload(
+                "cel_attribute_message_"
+                    + TestAllTypes.NestedMessage.getDescriptor().getFullName().replace('.', '_'),
+                StructTypeReference.create(
+                    TestAllTypes.NestedMessage.getDescriptor().getFullName()),
+                SimpleType.DYN,
+                ListType.create(SimpleType.DYN)));
+
+    assertThat(dynamicDecls).containsExactly(expectedDecl);
+  }
+
   @Test
   public void optimize_toParsedExpr_matchesExpectedSerializedProto() throws Exception {
     CelAbstractSyntaxTree ast = cel.compile("msg.single_nested_message.bb").getAst();
@@ -848,7 +1103,7 @@ public void optimize_toParsedExpr_matchesExpectedSerializedProto() throws Except
             "expr {\n"
                 + "  id: 1\n"
                 + "  call_expr {\n"
-                + "    function: \"cel.@attribute\"\n"
+                + "    function: \"cel.@attributeInt\"\n"
                 + "    args {\n"
                 + "      id: 2\n"
                 + "      ident_expr {\n"