diff --git a/tools/go-analyzer/types.go b/tools/go-analyzer/types.go
new file mode 100644
index 0000000..3cbeaba
--- /dev/null
+++ b/tools/go-analyzer/types.go
@@ -0,0 +1,77 @@
+package main
+
+// AnalysisResult holds all extracted data from Go source analysis.
+type AnalysisResult struct {
+	Modules      []Module
+	Dependencies []Dependency
+	Imports      []ImportInfo
+}
+
+// TotalFeatures returns the count of all features across all modules.
+func (r *AnalysisResult) TotalFeatures() int {
+	count := 0
+	for _, m := range r.Modules {
+		count += len(m.Features)
+	}
+	return count
+}
+
+// TotalTests returns the count of all tests across all modules.
+func (r *AnalysisResult) TotalTests() int {
+	count := 0
+	for _, m := range r.Modules {
+		count += len(m.Tests)
+	}
+	return count
+}
+
+// Module represents a logical grouping of Go source files.
+type Module struct {
+	Name        string
+	Description string
+	GoPackage   string
+	GoFile      string // primary file or directory
+	GoLineCount int
+	Features    []Feature
+	Tests       []TestFunc
+}
+
+// Feature represents a function or method extracted from Go source.
+type Feature struct {
+	Name         string
+	Description  string
+	GoFile       string
+	GoClass      string // receiver type, empty for package-level functions
+	GoMethod     string
+	GoLineNumber int
+	GoLineCount  int
+}
+
+// TestFunc represents a test function extracted from Go source.
+type TestFunc struct {
+	Name         string
+	Description  string
+	GoFile       string
+	GoClass      string
+	GoMethod     string
+	GoLineNumber int
+	GoLineCount  int
+	// FeatureName links this test to a feature by naming convention
+	FeatureName string
+}
+
+// Dependency represents a call relationship between two items.
+type Dependency struct {
+	SourceModule   string
+	SourceFeature  string // empty for module-level deps
+	TargetModule   string
+	TargetFeature  string // empty for module-level deps
+	DependencyKind string // "calls"
+}
+
+// ImportInfo represents a Go import path found in source files.
+type ImportInfo struct {
+	ImportPath  string
+	IsStdlib    bool
+	UsedInFiles []string
+}