diff --git a/toolchain/driver/testdata/semantics_builtin_nodes.carbon b/toolchain/driver/testdata/semantics_builtin_nodes.carbon
index 75b13af639b8..0ca7279febd1 100644
--- a/toolchain/driver/testdata/semantics_builtin_nodes.carbon
+++ b/toolchain/driver/testdata/semantics_builtin_nodes.carbon
@@ -17,7 +17,7 @@
 // CHECK:STDOUT: ]
 // CHECK:STDOUT: nodes: [
 // CHECK:STDOUT:   {kind: CrossReference, arg0: ir0, arg1: nodeTypeType, type: typeTypeType},
-// CHECK:STDOUT:   {kind: CrossReference, arg0: ir0, arg1: nodeInvalidType, type: typeInvalidType},
+// CHECK:STDOUT:   {kind: CrossReference, arg0: ir0, arg1: nodeError, type: typeError},
 // CHECK:STDOUT:   {kind: CrossReference, arg0: ir0, arg1: nodeBoolType, type: typeTypeType},
 // CHECK:STDOUT:   {kind: CrossReference, arg0: ir0, arg1: nodeIntegerType, type: typeTypeType},
 // CHECK:STDOUT:   {kind: CrossReference, arg0: ir0, arg1: nodeFloatingPointType, type: typeTypeType},
diff --git a/toolchain/semantics/semantics_builtin_kind.def b/toolchain/semantics/semantics_builtin_kind.def
index f54cbe9d6a32..267246b0583d 100644
--- a/toolchain/semantics/semantics_builtin_kind.def
+++ b/toolchain/semantics/semantics_builtin_kind.def
@@ -40,9 +40,11 @@
 // This has a deliberately self-referential type.
 CARBON_SEMANTICS_BUILTIN_KIND(TypeType, "Type")
 
-// Used when a SemanticNode has an invalid type, which should then be ignored
-// for future type checking.
-CARBON_SEMANTICS_BUILTIN_KIND(InvalidType, "<unknown>")
+// Used when a semantic error has been detected, and a SemanticNodeId is still
+// required. For example, when there is a type checking issue, this will be used
+// in the type_id. It's typically used as a cue that semantic checking doesn't
+// need to issue further diagnostics.
+CARBON_SEMANTICS_BUILTIN_KIND(Error, "<error>")
 
 // -----------------------------------------------------------------------------
 // TODO: Below types are all placeholders. While the above may last, the below
diff --git a/toolchain/semantics/semantics_context.cpp b/toolchain/semantics/semantics_context.cpp
index 271de8e13388..38e3b5319ea6 100644
--- a/toolchain/semantics/semantics_context.cpp
+++ b/toolchain/semantics/semantics_context.cpp
@@ -33,10 +33,10 @@ SemanticsContext::SemanticsContext(const TokenizedBuffer& tokens,
       params_or_args_stack_("params_or_args_stack_", semantics_ir, vlog_stream),
       args_type_info_stack_("args_type_info_stack_", semantics_ir,
                             vlog_stream) {
-  // Inserts the "Invalid" and "Type" types as "used types" so that
+  // Inserts the "Error" and "Type" types as "used types" so that
   // canonicalization can skip them. We don't emit either for lowering.
   canonical_types_.insert(
-      {SemanticsNodeId::BuiltinInvalidType, SemanticsTypeId::InvalidType});
+      {SemanticsNodeId::BuiltinError, SemanticsTypeId::Error});
   canonical_types_.insert(
       {SemanticsNodeId::BuiltinTypeType, SemanticsTypeId::TypeType});
 }
@@ -142,7 +142,7 @@ auto SemanticsContext::LookupName(ParseTree::Node parse_node,
         emitter_->Emit(parse_node, NameNotFound,
                        semantics_ir_->GetString(name_id));
       }
-      return SemanticsNodeId::BuiltinInvalidType;
+      return SemanticsNodeId::BuiltinError;
     }
     CARBON_CHECK(!it->second.empty())
         << "Should have been erased: " << semantics_ir_->GetString(name_id);
@@ -157,7 +157,7 @@ auto SemanticsContext::LookupName(ParseTree::Node parse_node,
         emitter_->Emit(parse_node, NameNotFound,
                        semantics_ir_->GetString(name_id));
       }
-      return SemanticsNodeId::BuiltinInvalidType;
+      return SemanticsNodeId::BuiltinError;
     }
 
     return it->second;
@@ -360,7 +360,7 @@ auto SemanticsContext::ApplyDeclarationNameQualifier(
         auto resolved_node_id = LookupName(name_context.parse_node, name_id,
                                            name_context.target_scope_id,
                                            /*print_diagnostics=*/false);
-        if (resolved_node_id == SemanticsNodeId::BuiltinInvalidType) {
+        if (resolved_node_id == SemanticsNodeId::BuiltinError) {
           // Invalid indicates an unresolved node. Store it and return.
           name_context.state = DeclarationNameContext::State::Unresolved;
           name_context.unresolved_name_id = name_id;
@@ -479,20 +479,20 @@ auto SemanticsContext::ImplicitAsImpl(SemanticsNodeId value_id,
     -> ImplicitAsKind {
   // Start by making sure both sides are valid. If any part is invalid, the
   // result is invalid and we shouldn't error.
-  if (value_id == SemanticsNodeId::BuiltinInvalidType) {
+  if (value_id == SemanticsNodeId::BuiltinError) {
     // If the value is invalid, we can't do much, but do "succeed".
     return ImplicitAsKind::Identical;
   }
   auto value = semantics_ir_->GetNode(value_id);
   auto value_type_id = value.type_id();
-  if (value_type_id == SemanticsTypeId::InvalidType) {
+  if (value_type_id == SemanticsTypeId::Error) {
     return ImplicitAsKind::Identical;
   }
 
-  if (as_type_id == SemanticsTypeId::InvalidType) {
+  if (as_type_id == SemanticsTypeId::Error) {
     // Although the target type is invalid, this still changes the value.
     if (output_value_id != nullptr) {
-      *output_value_id = SemanticsNodeId::BuiltinInvalidType;
+      *output_value_id = SemanticsNodeId::BuiltinError;
     }
     return ImplicitAsKind::Compatible;
   }
@@ -519,7 +519,7 @@ auto SemanticsContext::ImplicitAsImpl(SemanticsNodeId value_id,
   // TODO: Handle ImplicitAs for compatible structs and tuples.
 
   if (output_value_id != nullptr) {
-    *output_value_id = SemanticsNodeId::BuiltinInvalidType;
+    *output_value_id = SemanticsNodeId::BuiltinError;
   }
   return ImplicitAsKind::Incompatible;
 }
diff --git a/toolchain/semantics/semantics_context.h b/toolchain/semantics/semantics_context.h
index a087e049cd60..ed023ff646c5 100644
--- a/toolchain/semantics/semantics_context.h
+++ b/toolchain/semantics/semantics_context.h
@@ -210,7 +210,7 @@ class SemanticsContext {
       -> bool;
 
   // Runs ImplicitAsImpl for a situation where a cast is required, returning the
-  // updated `value_id`. Prints a diagnostic and returns an InvalidType if
+  // updated `value_id`. Prints a diagnostic and returns an Error if
   // unsupported.
   auto ImplicitAsRequired(ParseTree::Node parse_node, SemanticsNodeId value_id,
                           SemanticsTypeId as_type_id) -> SemanticsNodeId;
diff --git a/toolchain/semantics/semantics_handle.cpp b/toolchain/semantics/semantics_handle.cpp
index 9ad0cc899418..39c27fd69fda 100644
--- a/toolchain/semantics/semantics_handle.cpp
+++ b/toolchain/semantics/semantics_handle.cpp
@@ -238,7 +238,7 @@ auto SemanticsHandleMemberAccessExpression(SemanticsContext& context,
   }
 
   // Should only be reached on error.
-  context.node_stack().Push(parse_node, SemanticsNodeId::BuiltinInvalidType);
+  context.node_stack().Push(parse_node, SemanticsNodeId::BuiltinError);
   return true;
 }
 
diff --git a/toolchain/semantics/semantics_handle_call_expression.cpp b/toolchain/semantics/semantics_handle_call_expression.cpp
index 04840712aeda..5efe59d361ea 100644
--- a/toolchain/semantics/semantics_handle_call_expression.cpp
+++ b/toolchain/semantics/semantics_handle_call_expression.cpp
@@ -32,7 +32,7 @@ auto SemanticsHandleCallExpression(SemanticsContext& context,
   if (!context.ImplicitAsForArgs(refs_id, name_node.parse_node(),
                                  callable.param_refs_id, &diagnostic)) {
     diagnostic.Emit();
-    context.node_stack().Push(parse_node, SemanticsNodeId::BuiltinInvalidType);
+    context.node_stack().Push(parse_node, SemanticsNodeId::BuiltinError);
     return true;
   }
 
diff --git a/toolchain/semantics/semantics_ir.cpp b/toolchain/semantics/semantics_ir.cpp
index 278077eba0cd..f8a1f9a8533f 100644
--- a/toolchain/semantics/semantics_ir.cpp
+++ b/toolchain/semantics/semantics_ir.cpp
@@ -17,14 +17,14 @@ auto SemanticsIR::MakeBuiltinIR() -> SemanticsIR {
   SemanticsIR semantics_ir(/*builtin_ir=*/nullptr);
   semantics_ir.nodes_.reserve(SemanticsBuiltinKind::ValidCount);
 
-  // InvalidType uses a self-referential type so that it's not accidentally
-  // treated as a normal type. Every other builtin is a type, including the
+  // Error uses a self-referential type so that it's not accidentally treated as
+  // a normal type. Every other builtin is a type, including the
   // self-referential TypeType.
-#define CARBON_SEMANTICS_BUILTIN_KIND(Name, ...)                      \
-  semantics_ir.nodes_.push_back(SemanticsNode::Builtin::Make(         \
-      SemanticsBuiltinKind::Name,                                     \
-      SemanticsBuiltinKind::Name == SemanticsBuiltinKind::InvalidType \
-          ? SemanticsTypeId::InvalidType                              \
+#define CARBON_SEMANTICS_BUILTIN_KIND(Name, ...)                \
+  semantics_ir.nodes_.push_back(SemanticsNode::Builtin::Make(   \
+      SemanticsBuiltinKind::Name,                               \
+      SemanticsBuiltinKind::Name == SemanticsBuiltinKind::Error \
+          ? SemanticsTypeId::Error                              \
           : SemanticsTypeId::TypeType));
 #include "toolchain/semantics/semantics_builtin_kind.def"
 
diff --git a/toolchain/semantics/semantics_ir.h b/toolchain/semantics/semantics_ir.h
index b98966b7dfe9..37d4dcf323be 100644
--- a/toolchain/semantics/semantics_ir.h
+++ b/toolchain/semantics/semantics_ir.h
@@ -225,11 +225,11 @@ class SemanticsIR {
     return type_id;
   }
 
-  // Gets the node ID for a type. This doesn't handle TypeType or InvalidType in
+  // Gets the node ID for a type. This doesn't handle TypeType or Error in
   // order to avoid a check; callers that need that should use
   // GetTypeAllowBuiltinTypes.
   auto GetType(SemanticsTypeId type_id) const -> SemanticsNodeId {
-    // Double-check it's not called with TypeType or InvalidType.
+    // Double-check it's not called with TypeType or Error.
     CARBON_CHECK(type_id.index >= 0)
         << "Invalid argument for GetType: " << type_id;
     return types_[type_id.index];
@@ -239,8 +239,8 @@ class SemanticsIR {
       -> SemanticsNodeId {
     if (type_id == SemanticsTypeId::TypeType) {
       return SemanticsNodeId::BuiltinTypeType;
-    } else if (type_id == SemanticsTypeId::InvalidType) {
-      return SemanticsNodeId::BuiltinInvalidType;
+    } else if (type_id == SemanticsTypeId::Error) {
+      return SemanticsNodeId::BuiltinError;
     } else {
       return GetType(type_id);
     }
diff --git a/toolchain/semantics/semantics_node.h b/toolchain/semantics/semantics_node.h
index 6d0e2eb4ab02..4a098fcde7de 100644
--- a/toolchain/semantics/semantics_node.h
+++ b/toolchain/semantics/semantics_node.h
@@ -168,8 +168,8 @@ struct SemanticsTypeId : public IndexBase {
   // The builtin TypeType.
   static const SemanticsTypeId TypeType;
 
-  // The builtin InvalidType.
-  static const SemanticsTypeId InvalidType;
+  // The builtin Error.
+  static const SemanticsTypeId Error;
 
   // An explicitly invalid ID.
   static const SemanticsTypeId Invalid;
@@ -179,8 +179,8 @@ struct SemanticsTypeId : public IndexBase {
     out << "type";
     if (index == TypeType.index) {
       out << "TypeType";
-    } else if (index == InvalidType.index) {
-      out << "InvalidType";
+    } else if (index == Error.index) {
+      out << "Error";
     } else {
       IndexBase::Print(out);
     }
@@ -189,7 +189,7 @@ struct SemanticsTypeId : public IndexBase {
 
 constexpr SemanticsTypeId SemanticsTypeId::TypeType =
     SemanticsTypeId(SemanticsTypeId::InvalidIndex - 2);
-constexpr SemanticsTypeId SemanticsTypeId::InvalidType =
+constexpr SemanticsTypeId SemanticsTypeId::Error =
     SemanticsTypeId(SemanticsTypeId::InvalidIndex - 1);
 constexpr SemanticsTypeId SemanticsTypeId::Invalid =
     SemanticsTypeId(SemanticsTypeId::InvalidIndex);
diff --git a/toolchain/semantics/testdata/basics/fail_qualifier_unsupported.carbon b/toolchain/semantics/testdata/basics/fail_qualifier_unsupported.carbon
index d9417874cf16..c717544f0acf 100644
--- a/toolchain/semantics/testdata/basics/fail_qualifier_unsupported.carbon
+++ b/toolchain/semantics/testdata/basics/fail_qualifier_unsupported.carbon
@@ -23,7 +23,7 @@
 // CHECK:STDOUT:   {kind: BindName, arg0: str0, arg1: node+0, type: type0},
 // CHECK:STDOUT:   {kind: VarStorage, type: type0},
 // CHECK:STDOUT:   {kind: BindName, arg0: str1, arg1: node+2, type: type0},
-// CHECK:STDOUT:   {kind: Assign, arg0: node+2, arg1: nodeInvalidType, type: typeInvalidType},
+// CHECK:STDOUT:   {kind: Assign, arg0: node+2, arg1: nodeError, type: typeError},
 // CHECK:STDOUT: ]
 // CHECK:STDOUT: node_blocks: [
 // CHECK:STDOUT:   [
diff --git a/toolchain/semantics/testdata/function/call/fail_return_type_mismatch.carbon b/toolchain/semantics/testdata/function/call/fail_return_type_mismatch.carbon
index 2b0812a79c90..0e5142b3d7ad 100644
--- a/toolchain/semantics/testdata/function/call/fail_return_type_mismatch.carbon
+++ b/toolchain/semantics/testdata/function/call/fail_return_type_mismatch.carbon
@@ -31,7 +31,7 @@
 // CHECK:STDOUT:   {kind: VarStorage, type: type2},
 // CHECK:STDOUT:   {kind: BindName, arg0: str2, arg1: node+4, type: type2},
 // CHECK:STDOUT:   {kind: Call, arg0: block0, arg1: function0, type: type0},
-// CHECK:STDOUT:   {kind: Assign, arg0: node+4, arg1: nodeInvalidType, type: typeInvalidType},
+// CHECK:STDOUT:   {kind: Assign, arg0: node+4, arg1: nodeError, type: typeError},
 // CHECK:STDOUT:   {kind: Return},
 // CHECK:STDOUT: ]
 // CHECK:STDOUT: node_blocks: [
diff --git a/toolchain/semantics/testdata/if/fail_scope.carbon b/toolchain/semantics/testdata/if/fail_scope.carbon
index e54effa722f9..047dd811c5d7 100644
--- a/toolchain/semantics/testdata/if/fail_scope.carbon
+++ b/toolchain/semantics/testdata/if/fail_scope.carbon
@@ -33,7 +33,7 @@
 // CHECK:STDOUT:   {kind: Assign, arg0: node+5, arg1: node+7, type: type1},
 // CHECK:STDOUT:   {kind: ReturnExpression, arg0: node+5, type: type1},
 // CHECK:STDOUT:   {kind: Branch, arg0: block6},
-// CHECK:STDOUT:   {kind: ReturnExpression, arg0: nodeInvalidType, type: typeInvalidType},
+// CHECK:STDOUT:   {kind: ReturnExpression, arg0: nodeError, type: typeError},
 // CHECK:STDOUT: ]
 // CHECK:STDOUT: node_blocks: [
 // CHECK:STDOUT:   [
diff --git a/toolchain/semantics/testdata/operators/fail_type_mismatch.carbon b/toolchain/semantics/testdata/operators/fail_type_mismatch.carbon
index cd488d5de806..505744e2d935 100644
--- a/toolchain/semantics/testdata/operators/fail_type_mismatch.carbon
+++ b/toolchain/semantics/testdata/operators/fail_type_mismatch.carbon
@@ -24,8 +24,8 @@
 // CHECK:STDOUT:   {kind: FunctionDeclaration, arg0: function0},
 // CHECK:STDOUT:   {kind: IntegerLiteral, arg0: int0, type: type0},
 // CHECK:STDOUT:   {kind: RealLiteral, arg0: real0, type: type1},
-// CHECK:STDOUT:   {kind: BinaryOperatorAdd, arg0: nodeInvalidType, arg1: node+2, type: typeInvalidType},
-// CHECK:STDOUT:   {kind: ReturnExpression, arg0: node+3, type: typeInvalidType},
+// CHECK:STDOUT:   {kind: BinaryOperatorAdd, arg0: nodeError, arg1: node+2, type: typeError},
+// CHECK:STDOUT:   {kind: ReturnExpression, arg0: node+3, type: typeError},
 // CHECK:STDOUT: ]
 // CHECK:STDOUT: node_blocks: [
 // CHECK:STDOUT:   [
diff --git a/toolchain/semantics/testdata/operators/fail_type_mismatch_once.carbon b/toolchain/semantics/testdata/operators/fail_type_mismatch_once.carbon
index 84320fcf0fc8..8903b32c657d 100644
--- a/toolchain/semantics/testdata/operators/fail_type_mismatch_once.carbon
+++ b/toolchain/semantics/testdata/operators/fail_type_mismatch_once.carbon
@@ -25,10 +25,10 @@
 // CHECK:STDOUT:   {kind: FunctionDeclaration, arg0: function0},
 // CHECK:STDOUT:   {kind: IntegerLiteral, arg0: int0, type: type0},
 // CHECK:STDOUT:   {kind: RealLiteral, arg0: real0, type: type1},
-// CHECK:STDOUT:   {kind: BinaryOperatorAdd, arg0: nodeInvalidType, arg1: node+2, type: typeInvalidType},
+// CHECK:STDOUT:   {kind: BinaryOperatorAdd, arg0: nodeError, arg1: node+2, type: typeError},
 // CHECK:STDOUT:   {kind: IntegerLiteral, arg0: int1, type: type0},
-// CHECK:STDOUT:   {kind: BinaryOperatorAdd, arg0: node+3, arg1: node+4, type: typeInvalidType},
-// CHECK:STDOUT:   {kind: ReturnExpression, arg0: node+5, type: typeInvalidType},
+// CHECK:STDOUT:   {kind: BinaryOperatorAdd, arg0: node+3, arg1: node+4, type: typeError},
+// CHECK:STDOUT:   {kind: ReturnExpression, arg0: node+5, type: typeError},
 // CHECK:STDOUT: ]
 // CHECK:STDOUT: node_blocks: [
 // CHECK:STDOUT:   [
diff --git a/toolchain/semantics/testdata/return/fail_type_mismatch.carbon b/toolchain/semantics/testdata/return/fail_type_mismatch.carbon
index 6ec2be50512c..801cee6437b1 100644
--- a/toolchain/semantics/testdata/return/fail_type_mismatch.carbon
+++ b/toolchain/semantics/testdata/return/fail_type_mismatch.carbon
@@ -22,7 +22,7 @@
 // CHECK:STDOUT: nodes: [
 // CHECK:STDOUT:   {kind: FunctionDeclaration, arg0: function0},
 // CHECK:STDOUT:   {kind: RealLiteral, arg0: real0, type: type1},
-// CHECK:STDOUT:   {kind: ReturnExpression, arg0: nodeInvalidType, type: typeInvalidType},
+// CHECK:STDOUT:   {kind: ReturnExpression, arg0: nodeError, type: typeError},
 // CHECK:STDOUT: ]
 // CHECK:STDOUT: node_blocks: [
 // CHECK:STDOUT:   [
diff --git a/toolchain/semantics/testdata/struct/fail_assign_empty.carbon b/toolchain/semantics/testdata/struct/fail_assign_empty.carbon
index cc89d6534887..cd0900d5587d 100644
--- a/toolchain/semantics/testdata/struct/fail_assign_empty.carbon
+++ b/toolchain/semantics/testdata/struct/fail_assign_empty.carbon
@@ -26,7 +26,7 @@
 // CHECK:STDOUT:   {kind: BindName, arg0: str0, arg1: node+2, type: type1},
 // CHECK:STDOUT:   {kind: StructType, arg0: block0, type: typeTypeType},
 // CHECK:STDOUT:   {kind: StructValue, arg0: block0, type: type2},
-// CHECK:STDOUT:   {kind: Assign, arg0: node+2, arg1: nodeInvalidType, type: typeInvalidType},
+// CHECK:STDOUT:   {kind: Assign, arg0: node+2, arg1: nodeError, type: typeError},
 // CHECK:STDOUT: ]
 // CHECK:STDOUT: node_blocks: [
 // CHECK:STDOUT:   [
diff --git a/toolchain/semantics/testdata/struct/fail_assign_to_empty.carbon b/toolchain/semantics/testdata/struct/fail_assign_to_empty.carbon
index 7d662d13d16e..ccfc11e9e934 100644
--- a/toolchain/semantics/testdata/struct/fail_assign_to_empty.carbon
+++ b/toolchain/semantics/testdata/struct/fail_assign_to_empty.carbon
@@ -30,7 +30,7 @@
 // CHECK:STDOUT:   {kind: StubReference, arg0: node+4, type: type1},
 // CHECK:STDOUT:   {kind: StructType, arg0: block2, type: typeTypeType},
 // CHECK:STDOUT:   {kind: StructValue, arg0: block3, type: type2},
-// CHECK:STDOUT:   {kind: Assign, arg0: node+2, arg1: nodeInvalidType, type: typeInvalidType},
+// CHECK:STDOUT:   {kind: Assign, arg0: node+2, arg1: nodeError, type: typeError},
 // CHECK:STDOUT: ]
 // CHECK:STDOUT: node_blocks: [
 // CHECK:STDOUT:   [
diff --git a/toolchain/semantics/testdata/struct/fail_field_name_mismatch.carbon b/toolchain/semantics/testdata/struct/fail_field_name_mismatch.carbon
index ba03644d70f7..ad837a4690a1 100644
--- a/toolchain/semantics/testdata/struct/fail_field_name_mismatch.carbon
+++ b/toolchain/semantics/testdata/struct/fail_field_name_mismatch.carbon
@@ -31,7 +31,7 @@
 // CHECK:STDOUT:   {kind: StubReference, arg0: node+4, type: type0},
 // CHECK:STDOUT:   {kind: StructType, arg0: block3, type: typeTypeType},
 // CHECK:STDOUT:   {kind: StructValue, arg0: block4, type: type2},
-// CHECK:STDOUT:   {kind: Assign, arg0: node+2, arg1: nodeInvalidType, type: typeInvalidType},
+// CHECK:STDOUT:   {kind: Assign, arg0: node+2, arg1: nodeError, type: typeError},
 // CHECK:STDOUT: ]
 // CHECK:STDOUT: node_blocks: [
 // CHECK:STDOUT:   [
diff --git a/toolchain/semantics/testdata/struct/fail_field_type_mismatch.carbon b/toolchain/semantics/testdata/struct/fail_field_type_mismatch.carbon
index 5047ffb382e7..8b2a535f253e 100644
--- a/toolchain/semantics/testdata/struct/fail_field_type_mismatch.carbon
+++ b/toolchain/semantics/testdata/struct/fail_field_type_mismatch.carbon
@@ -32,7 +32,7 @@
 // CHECK:STDOUT:   {kind: StubReference, arg0: node+4, type: type2},
 // CHECK:STDOUT:   {kind: StructType, arg0: block3, type: typeTypeType},
 // CHECK:STDOUT:   {kind: StructValue, arg0: block4, type: type3},
-// CHECK:STDOUT:   {kind: Assign, arg0: node+2, arg1: nodeInvalidType, type: typeInvalidType},
+// CHECK:STDOUT:   {kind: Assign, arg0: node+2, arg1: nodeError, type: typeError},
 // CHECK:STDOUT: ]
 // CHECK:STDOUT: node_blocks: [
 // CHECK:STDOUT:   [
diff --git a/toolchain/semantics/testdata/struct/fail_member_access_type.carbon b/toolchain/semantics/testdata/struct/fail_member_access_type.carbon
index f9fe0d8d44d6..09a01d6e7d53 100644
--- a/toolchain/semantics/testdata/struct/fail_member_access_type.carbon
+++ b/toolchain/semantics/testdata/struct/fail_member_access_type.carbon
@@ -34,7 +34,7 @@
 // CHECK:STDOUT:   {kind: Assign, arg0: node+2, arg1: node+7, type: type1},
 // CHECK:STDOUT:   {kind: VarStorage, type: type2},
 // CHECK:STDOUT:   {kind: BindName, arg0: str2, arg1: node+9, type: type2},
-// CHECK:STDOUT:   {kind: Assign, arg0: node+9, arg1: nodeInvalidType, type: typeInvalidType},
+// CHECK:STDOUT:   {kind: Assign, arg0: node+9, arg1: nodeError, type: typeError},
 // CHECK:STDOUT: ]
 // CHECK:STDOUT: node_blocks: [
 // CHECK:STDOUT:   [
diff --git a/toolchain/semantics/testdata/struct/fail_non_member_access.carbon b/toolchain/semantics/testdata/struct/fail_non_member_access.carbon
index 4bb69fa0c175..3c4851f579e0 100644
--- a/toolchain/semantics/testdata/struct/fail_non_member_access.carbon
+++ b/toolchain/semantics/testdata/struct/fail_non_member_access.carbon
@@ -33,7 +33,7 @@
 // CHECK:STDOUT:   {kind: Assign, arg0: node+2, arg1: node+7, type: type1},
 // CHECK:STDOUT:   {kind: VarStorage, type: type0},
 // CHECK:STDOUT:   {kind: BindName, arg0: str2, arg1: node+9, type: type0},
-// CHECK:STDOUT:   {kind: Assign, arg0: node+9, arg1: nodeInvalidType, type: typeInvalidType},
+// CHECK:STDOUT:   {kind: Assign, arg0: node+9, arg1: nodeError, type: typeError},
 // CHECK:STDOUT: ]
 // CHECK:STDOUT: node_blocks: [
 // CHECK:STDOUT:   [
diff --git a/toolchain/semantics/testdata/struct/fail_too_few_values.carbon b/toolchain/semantics/testdata/struct/fail_too_few_values.carbon
index 540986605900..fab7df9ad838 100644
--- a/toolchain/semantics/testdata/struct/fail_too_few_values.carbon
+++ b/toolchain/semantics/testdata/struct/fail_too_few_values.carbon
@@ -32,7 +32,7 @@
 // CHECK:STDOUT:   {kind: StubReference, arg0: node+5, type: type0},
 // CHECK:STDOUT:   {kind: StructType, arg0: block3, type: typeTypeType},
 // CHECK:STDOUT:   {kind: StructValue, arg0: block4, type: type2},
-// CHECK:STDOUT:   {kind: Assign, arg0: node+3, arg1: nodeInvalidType, type: typeInvalidType},
+// CHECK:STDOUT:   {kind: Assign, arg0: node+3, arg1: nodeError, type: typeError},
 // CHECK:STDOUT: ]
 // CHECK:STDOUT: node_blocks: [
 // CHECK:STDOUT:   [
diff --git a/toolchain/semantics/testdata/struct/fail_type_assign.carbon b/toolchain/semantics/testdata/struct/fail_type_assign.carbon
index 6f48db90b8cb..0fcd219ab00a 100644
--- a/toolchain/semantics/testdata/struct/fail_type_assign.carbon
+++ b/toolchain/semantics/testdata/struct/fail_type_assign.carbon
@@ -24,7 +24,7 @@
 // CHECK:STDOUT:   {kind: VarStorage, type: type1},
 // CHECK:STDOUT:   {kind: BindName, arg0: str0, arg1: node+2, type: type1},
 // CHECK:STDOUT:   {kind: StructTypeField, arg0: str1, type: type0},
-// CHECK:STDOUT:   {kind: Assign, arg0: node+2, arg1: nodeInvalidType, type: typeInvalidType},
+// CHECK:STDOUT:   {kind: Assign, arg0: node+2, arg1: nodeError, type: typeError},
 // CHECK:STDOUT: ]
 // CHECK:STDOUT: node_blocks: [
 // CHECK:STDOUT:   [
diff --git a/toolchain/semantics/testdata/struct/fail_value_as_type.carbon b/toolchain/semantics/testdata/struct/fail_value_as_type.carbon
index d29de60147c6..e7eb0a953d68 100644
--- a/toolchain/semantics/testdata/struct/fail_value_as_type.carbon
+++ b/toolchain/semantics/testdata/struct/fail_value_as_type.carbon
@@ -25,8 +25,8 @@
 // CHECK:STDOUT:   {kind: StubReference, arg0: node+0, type: type0},
 // CHECK:STDOUT:   {kind: StructType, arg0: block2, type: typeTypeType},
 // CHECK:STDOUT:   {kind: StructValue, arg0: block3, type: type1},
-// CHECK:STDOUT:   {kind: VarStorage, type: typeInvalidType},
-// CHECK:STDOUT:   {kind: BindName, arg0: str0, arg1: node+5, type: typeInvalidType},
+// CHECK:STDOUT:   {kind: VarStorage, type: typeError},
+// CHECK:STDOUT:   {kind: BindName, arg0: str0, arg1: node+5, type: typeError},
 // CHECK:STDOUT: ]
 // CHECK:STDOUT: node_blocks: [
 // CHECK:STDOUT:   [
diff --git a/toolchain/semantics/testdata/var/fail_init_type_mismatch.carbon b/toolchain/semantics/testdata/var/fail_init_type_mismatch.carbon
index 92d1f9ccf82b..0b0fa0adfc47 100644
--- a/toolchain/semantics/testdata/var/fail_init_type_mismatch.carbon
+++ b/toolchain/semantics/testdata/var/fail_init_type_mismatch.carbon
@@ -26,7 +26,7 @@
 // CHECK:STDOUT:   {kind: VarStorage, type: type1},
 // CHECK:STDOUT:   {kind: BindName, arg0: str1, arg1: node+1, type: type1},
 // CHECK:STDOUT:   {kind: RealLiteral, arg0: real0, type: type2},
-// CHECK:STDOUT:   {kind: Assign, arg0: node+1, arg1: nodeInvalidType, type: typeInvalidType},
+// CHECK:STDOUT:   {kind: Assign, arg0: node+1, arg1: nodeError, type: typeError},
 // CHECK:STDOUT:   {kind: Return},
 // CHECK:STDOUT: ]
 // CHECK:STDOUT: node_blocks: [
diff --git a/toolchain/semantics/testdata/var/fail_init_with_self.carbon b/toolchain/semantics/testdata/var/fail_init_with_self.carbon
index 6d48d4ce8af9..22f9ec5624ae 100644
--- a/toolchain/semantics/testdata/var/fail_init_with_self.carbon
+++ b/toolchain/semantics/testdata/var/fail_init_with_self.carbon
@@ -23,7 +23,7 @@
 // CHECK:STDOUT:   {kind: FunctionDeclaration, arg0: function0},
 // CHECK:STDOUT:   {kind: VarStorage, type: type1},
 // CHECK:STDOUT:   {kind: BindName, arg0: str1, arg1: node+1, type: type1},
-// CHECK:STDOUT:   {kind: Assign, arg0: node+1, arg1: nodeInvalidType, type: typeInvalidType},
+// CHECK:STDOUT:   {kind: Assign, arg0: node+1, arg1: nodeError, type: typeError},
 // CHECK:STDOUT:   {kind: Return},
 // CHECK:STDOUT: ]
 // CHECK:STDOUT: node_blocks: [
diff --git a/toolchain/semantics/testdata/var/fail_lookup_outside_scope.carbon b/toolchain/semantics/testdata/var/fail_lookup_outside_scope.carbon
index 7be851a90eea..f4c78e5acd2a 100644
--- a/toolchain/semantics/testdata/var/fail_lookup_outside_scope.carbon
+++ b/toolchain/semantics/testdata/var/fail_lookup_outside_scope.carbon
@@ -27,7 +27,7 @@
 // CHECK:STDOUT:   {kind: Return},
 // CHECK:STDOUT:   {kind: VarStorage, type: type1},
 // CHECK:STDOUT:   {kind: BindName, arg0: str2, arg1: node+4, type: type1},
-// CHECK:STDOUT:   {kind: Assign, arg0: node+4, arg1: nodeInvalidType, type: typeInvalidType},
+// CHECK:STDOUT:   {kind: Assign, arg0: node+4, arg1: nodeError, type: typeError},
 // CHECK:STDOUT: ]
 // CHECK:STDOUT: node_blocks: [
 // CHECK:STDOUT:   [
diff --git a/toolchain/semantics/testdata/var/fail_storage_is_literal.carbon b/toolchain/semantics/testdata/var/fail_storage_is_literal.carbon
index bde1601a1b1e..8f2b870c3f5d 100644
--- a/toolchain/semantics/testdata/var/fail_storage_is_literal.carbon
+++ b/toolchain/semantics/testdata/var/fail_storage_is_literal.carbon
@@ -24,10 +24,10 @@
 // CHECK:STDOUT: nodes: [
 // CHECK:STDOUT:   {kind: FunctionDeclaration, arg0: function0},
 // CHECK:STDOUT:   {kind: IntegerLiteral, arg0: int0, type: type1},
-// CHECK:STDOUT:   {kind: VarStorage, type: typeInvalidType},
-// CHECK:STDOUT:   {kind: BindName, arg0: str1, arg1: node+2, type: typeInvalidType},
+// CHECK:STDOUT:   {kind: VarStorage, type: typeError},
+// CHECK:STDOUT:   {kind: BindName, arg0: str1, arg1: node+2, type: typeError},
 // CHECK:STDOUT:   {kind: IntegerLiteral, arg0: int1, type: type1},
-// CHECK:STDOUT:   {kind: Assign, arg0: node+2, arg1: nodeInvalidType, type: typeInvalidType},
+// CHECK:STDOUT:   {kind: Assign, arg0: node+2, arg1: nodeError, type: typeError},
 // CHECK:STDOUT:   {kind: Return},
 // CHECK:STDOUT: ]
 // CHECK:STDOUT: node_blocks: [