diff --git a/bp2build/build_conversion.go b/bp2build/build_conversion.go
index a860484..46a5bd8 100644
--- a/bp2build/build_conversion.go
+++ b/bp2build/build_conversion.go
@@ -28,6 +28,7 @@
 	"android/soong/android"
 	"android/soong/bazel"
 	"android/soong/starlark_fmt"
+	"android/soong/ui/metrics/bp2build_metrics_proto"
 	"github.com/google/blueprint"
 	"github.com/google/blueprint/proptools"
 )
@@ -283,12 +284,15 @@
 				// target in a BUILD file, we don't autoconvert them.
 
 				// Log the module.
-				metrics.AddConvertedModule(m, moduleType, dir, Handcrafted)
+				metrics.AddUnconvertedModule(m, moduleType, dir,
+					android.UnconvertedReason{
+						ReasonType: int(bp2build_metrics_proto.UnconvertedReasonType_DEFINED_IN_BUILD_FILE),
+					})
 			} else if aModule, ok := m.(android.Module); ok && aModule.IsConvertedByBp2build() {
 				// Handle modules converted to generated targets.
 
 				// Log the module.
-				metrics.AddConvertedModule(aModule, moduleType, dir, Generated)
+				metrics.AddConvertedModule(aModule, moduleType, dir)
 
 				// Handle modules with unconverted deps. By default, emit a warning.
 				if unconvertedDeps := aModule.GetUnconvertedBp2buildDeps(); len(unconvertedDeps) > 0 {
@@ -324,8 +328,18 @@
 			} else if _, ok := ctx.Config().BazelModulesForceEnabledByFlag()[m.Name()]; ok && m.Name() != "" {
 				err := fmt.Errorf("Force Enabled Module %s not converted", m.Name())
 				errs = append(errs, err)
+			} else if aModule, ok := m.(android.Module); ok {
+				reason := aModule.GetUnconvertedReason()
+				if reason == nil {
+					panic(fmt.Errorf("module '%s' was neither converted nor marked unconvertible with bp2build", aModule.Name()))
+				} else {
+					metrics.AddUnconvertedModule(m, moduleType, dir, *reason)
+				}
+				return
 			} else {
-				metrics.AddUnconvertedModule(moduleType)
+				metrics.AddUnconvertedModule(m, moduleType, dir, android.UnconvertedReason{
+					ReasonType: int(bp2build_metrics_proto.UnconvertedReasonType_TYPE_UNSUPPORTED),
+				})
 				return
 			}
 		case QueryView:
diff --git a/bp2build/metrics.go b/bp2build/metrics.go
index a020650..00f21c8 100644
--- a/bp2build/metrics.go
+++ b/bp2build/metrics.go
@@ -38,6 +38,7 @@
 			RuleClassCount:           make(map[string]uint64),
 			ConvertedModuleTypeCount: make(map[string]uint64),
 			TotalModuleTypeCount:     make(map[string]uint64),
+			UnconvertedModules:       make(map[string]*bp2build_metrics_proto.UnconvertedReason),
 		},
 		convertedModulePathMap: make(map[string]string),
 	}
@@ -149,11 +150,6 @@
 	metrics.serialized.Events = append(metrics.serialized.Events, event)
 }
 
-func (metrics *CodegenMetrics) AddUnconvertedModule(moduleType string) {
-	metrics.serialized.UnconvertedModuleCount += 1
-	metrics.serialized.TotalModuleTypeCount[moduleType] += 1
-}
-
 func (metrics *CodegenMetrics) SetSymlinkCount(n uint64) {
 	if m := metrics.serialized.WorkspaceSymlinkCount; m != 0 {
 		fmt.Fprintf(os.Stderr, "unexpected non-zero workspaceSymlinkCount of %d", m)
@@ -187,7 +183,7 @@
 	Handcrafted
 )
 
-func (metrics *CodegenMetrics) AddConvertedModule(m blueprint.Module, moduleType string, dir string, conversionType ConversionType) {
+func (metrics *CodegenMetrics) AddConvertedModule(m blueprint.Module, moduleType string, dir string) {
 	//a package module has empty name
 	if moduleType == "package" {
 		return
@@ -198,10 +194,25 @@
 	metrics.convertedModulePathMap[moduleName] = "//" + dir
 	metrics.serialized.ConvertedModuleTypeCount[moduleType] += 1
 	metrics.serialized.TotalModuleTypeCount[moduleType] += 1
+	metrics.serialized.GeneratedModuleCount += 1
+}
 
-	if conversionType == Handcrafted {
+func (metrics *CodegenMetrics) AddUnconvertedModule(m blueprint.Module, moduleType string, dir string,
+	reason android.UnconvertedReason) {
+	//a package module has empty name
+	if moduleType == "package" {
+		return
+	}
+	// Undo prebuilt_ module name prefix modifications
+	moduleName := android.RemoveOptionalPrebuiltPrefix(m.Name())
+	metrics.serialized.UnconvertedModules[moduleName] = &bp2build_metrics_proto.UnconvertedReason{
+		Type:   bp2build_metrics_proto.UnconvertedReasonType(reason.ReasonType),
+		Detail: reason.Detail,
+	}
+	metrics.serialized.UnconvertedModuleCount += 1
+	metrics.serialized.TotalModuleTypeCount[moduleType] += 1
+
+	if reason.ReasonType == int(bp2build_metrics_proto.UnconvertedReasonType_DEFINED_IN_BUILD_FILE) {
 		metrics.serialized.HandCraftedModuleCount += 1
-	} else if conversionType == Generated {
-		metrics.serialized.GeneratedModuleCount += 1
 	}
 }
diff --git a/bp2build/testing.go b/bp2build/testing.go
index f3263a1..140b214 100644
--- a/bp2build/testing.go
+++ b/bp2build/testing.go
@@ -78,7 +78,7 @@
 	ModuleTypeUnderTestFactory android.ModuleFactory
 	// Text to add to the toplevel, root Android.bp file. If Dir is not set, all
 	// ExpectedBazelTargets are assumed to be generated by this file.
-	Blueprint            string
+	Blueprint string
 	// ExpectedBazelTargets compares the BazelTargets generated in `Dir` (if not empty).
 	// Otherwise, it checks the BazelTargets generated by `Blueprint` in the root directory.
 	ExpectedBazelTargets []string
@@ -146,6 +146,10 @@
 				})
 			}
 			ctx.RegisterBp2BuildConfig(bp2buildConfig)
+			// This setting is added to bp2build invocations. It prevents bp2build
+			// from cloning modules to their original state after mutators run. This
+			// would lose some data intentionally set by these mutators.
+			ctx.SkipCloneModulesAfterMutators = true
 		}),
 		android.FixtureModifyEnv(func(env map[string]string) {
 			if tc.UnconvertedDepsMode == errorModulesUnconvertedDeps {
@@ -210,7 +214,11 @@
 		return
 	}
 
-	codegenCtx := NewCodegenContext(config, ctx.Context, Bp2Build, "")
+	codegenMode := Bp2Build
+	if ctx.Config().BuildMode == android.ApiBp2build {
+		codegenMode = ApiBp2build
+	}
+	codegenCtx := NewCodegenContext(config, ctx.Context, codegenMode, "")
 	res, errs := GenerateBazelTargets(codegenCtx, false)
 	if bazelResult.CollateErrs(errs) {
 		return