feat(session): persist review and investigation provenance

cli/checkpoint/checkpoint.go

@@ -273,6 +273,21 @@ type WriteCommittedOptions struct {
 	// TurnID correlates checkpoints from the same agent turn.
 	TurnID string
 
+	// Kind tags the session purpose (e.g., "agent_review", "agent_investigate").
+	Kind string
+
+	// ReviewSkills is the snapshot of configured review skills at session start.
+	ReviewSkills []string
+
+	// ReviewPrompt is the actual text of the review request.
+	ReviewPrompt string
+
+	// InvestigateRunID is the 12-hex-char ID of the parent investigation run.
+	InvestigateRunID string
+
+	// InvestigateTopic is the human-readable topic for the investigation run.
+	InvestigateTopic string
+
 	// Transcript position at checkpoint start - tracks what was added during this checkpoint
 	TranscriptIdentifierAtStart string // Last identifier when checkpoint started (UUID for Claude, message ID for Gemini)
 	CheckpointTranscriptStart   int    // Transcript line offset at start of this checkpoint's data
@@ -470,6 +485,9 @@ type CommittedMetadata struct {
 	// run. Only set when Kind is an investigate kind.
 	InvestigateRunID string `json:"investigate_run_id,omitempty"`
 
+	// InvestigateTopic is the human-readable topic for the investigation run.
+	InvestigateTopic string `json:"investigate_topic,omitempty"`
+
 	// Task checkpoint fields (only populated for task checkpoints)
 	IsTask    bool   `json:"is_task,omitempty"`
 	ToolUseID string `json:"tool_use_id,omitempty"`

cli/checkpoint/committed.go

@@ -414,6 +414,11 @@ func (s *GitStore) writeSessionToSubdirectory(ctx context.Context, opts WriteCom
 		Agent:                       opts.Agent,
 		Model:                       opts.Model,
 		TurnID:                      opts.TurnID,
+		Kind:                        opts.Kind,
+		ReviewSkills:                opts.ReviewSkills,
+		ReviewPrompt:                opts.ReviewPrompt,
+		InvestigateRunID:            opts.InvestigateRunID,
+		InvestigateTopic:            opts.InvestigateTopic,
 		IsTask:                      opts.IsTask,
 		ToolUseID:                   opts.ToolUseID,
 		TranscriptIdentifierAtStart: opts.TranscriptIdentifierAtStart,
@@ -474,6 +479,8 @@ func (s *GitStore) writeCheckpointSummary(opts WriteCommittedOptions, basePath s
 		Sessions:            sessions,
 		TokenUsage:          tokenUsage,
 		CombinedAttribution: combinedAttribution,
+		HasReview:           opts.Kind == "agent_review",
+		HasInvestigation:    opts.Kind == "agent_investigate",
 	}
 
 	metadataJSON, err := jsonutil.MarshalIndentWithNewline(summary, "", "  ")

cli/checkpoint/v2_committed.go

@@ -572,6 +572,11 @@ func (s *V2GitStore) writeMainSessionToSubdirectory(opts WriteCommittedOptions,
 		Agent:                       opts.Agent,
 		Model:                       opts.Model,
 		TurnID:                      opts.TurnID,
+		Kind:                        opts.Kind,
+		ReviewSkills:                opts.ReviewSkills,
+		ReviewPrompt:                opts.ReviewPrompt,
+		InvestigateRunID:            opts.InvestigateRunID,
+		InvestigateTopic:            opts.InvestigateTopic,
 		IsTask:                      opts.IsTask,
 		ToolUseID:                   opts.ToolUseID,
 		TranscriptIdentifierAtStart: opts.TranscriptIdentifierAtStart,

cli/integration_test/hooks.go

@@ -73,6 +73,24 @@ func (r *HookRunner) SimulateUserPromptSubmitWithPrompt(sessionID, prompt string
 	return r.runHookWithInput("user-prompt-submit", input)
 }
 
+func (r *HookRunner) SimulateUserPromptSubmitWithReviewEnvVars(sessionID, prompt string, extraEnv []string) error {
+	r.T.Helper()
+	input := map[string]string{
+		"session_id":      sessionID,
+		"transcript_path": "",
+		"prompt":          prompt,
+	}
+	inputJSON, err := json.Marshal(input)
+	if err != nil {
+		return fmt.Errorf("failed to marshal hook input: %w", err)
+	}
+	out := r.runAgentHookWithOutput("claude-code", "user-prompt-submit", inputJSON, extraEnv...)
+	if out.Err != nil {
+		return fmt.Errorf("hook user-prompt-submit failed: %w\nInput: %s\nOutput: %s%s", out.Err, inputJSON, out.Stdout, out.Stderr)
+	}
+	return nil
+}
+
 // SimulateUserPromptSubmitWithTranscriptPath simulates the UserPromptSubmit hook
 // with an explicit transcript path. This is needed for mid-session commit detection
 // which reads the live transcript to detect ongoing sessions.
@@ -320,6 +338,12 @@ func (env *TestEnv) SimulateUserPromptSubmitWithPrompt(sessionID, prompt string)
 	return runner.SimulateUserPromptSubmitWithPrompt(sessionID, prompt)
 }
 
+func (env *TestEnv) SimulateUserPromptSubmitWithReviewEnvVars(sessionID, prompt string, extraEnv []string) error {
+	env.T.Helper()
+	runner := NewHookRunner(env.RepoDir, env.ClaudeProjectDir, env.T)
+	return runner.SimulateUserPromptSubmitWithReviewEnvVars(sessionID, prompt, extraEnv)
+}
+
 // SimulateUserPromptSubmitWithTranscriptPath is a convenience method on TestEnv.
 // This is needed for mid-session commit detection which reads the live transcript.
 func (env *TestEnv) SimulateUserPromptSubmitWithTranscriptPath(sessionID, transcriptPath string) error {

cli/integration_test/resume_test.go

@@ -570,6 +570,7 @@ func (env *TestEnv) GitCheckoutBranch(branchName string) {
 
 	err = worktree.Checkout(&git.CheckoutOptions{
 		Branch: plumbing.NewBranchReferenceName(branchName),
+		Force:  true,
 	})
 	if err != nil {
 		env.T.Fatalf("failed to checkout branch %s: %v", branchName, err)

cli/integration_test/testenv.go

@@ -380,6 +380,28 @@ func (env *TestEnv) initTraceInternal(strategyOptions map[string]any) {
 	}
 }
 
+func (env *TestEnv) WriteSettings(settings map[string]any) {
+	env.T.Helper()
+	traceDir := filepath.Join(env.RepoDir, paths.TraceDir)
+	if err := os.MkdirAll(traceDir, 0o755); err != nil {
+		env.T.Fatalf("failed to create .trace directory: %v", err)
+	}
+	data, err := jsonutil.MarshalIndentWithNewline(settings, "", "  ")
+	if err != nil {
+		env.T.Fatalf("failed to marshal settings: %v", err)
+	}
+	if err := os.WriteFile(filepath.Join(traceDir, paths.SettingsFileName), data, 0o644); err != nil {
+		env.T.Fatalf("failed to write %s: %v", paths.SettingsFileName, err)
+	}
+}
+
+func composeReviewPromptForTest(skills []string) string {
+	if len(skills) == 0 {
+		return "Review the current branch changes and report actionable findings."
+	}
+	return strings.Join(skills, "\n") + "\n\nReview the current branch changes and report actionable findings."
+}
+
 // WriteFile creates a file with the given content in the test repo.
 // It creates parent directories as needed.
 func (env *TestEnv) WriteFile(path, content string) {

cli/session/state.go

@@ -62,6 +62,9 @@ const (
 	// distinct Kind values AND added to Kind.IsReview so the checkpoint's
 	// HasReview umbrella flag keeps covering them.
 	KindAgentReview Kind = "agent_review"
+
+	// KindAgentInvestigate tags a session created by `trace investigate`.
+	KindAgentInvestigate Kind = "agent_investigate"
 )
 
 // IsReview reports whether this Kind counts as "a review happened" for the
@@ -72,6 +75,11 @@ func (k Kind) IsReview() bool {
 	return k == KindAgentReview
 }
 
+// IsInvestigation reports whether this Kind counts as an investigation session.
+func (k Kind) IsInvestigation() bool {
+	return k == KindAgentInvestigate
+}
+
 // State represents the state of an active session.
 // This is stored in .git/trace-sessions/<session-id>.json
 type State struct {
@@ -125,6 +133,12 @@ type State struct {
 	// prompt (attach path). Always populated when Kind is a review kind.
 	ReviewPrompt string `json:"review_prompt,omitempty"`
 
+	// InvestigateRunID is the 12-hex-char ID of the parent investigation run.
+	InvestigateRunID string `json:"investigate_run_id,omitempty"`
+
+	// InvestigateTopic is the human-readable topic for the investigation run.
+	InvestigateTopic string `json:"investigate_topic,omitempty"`
+
 	// TurnID is a unique identifier for the current agent turn.
 	// Lifecycle:
 	//   - Generated fresh in InitializeSession at each turn start

cli/strategy/manual_commit_condensation.go

@@ -227,6 +227,11 @@ func (s *ManualCommitStrategy) CondenseSession(ctx context.Context, repo *git.Re
 		Agent:                       state.AgentType,
 		Model:                       state.ModelName,
 		TurnID:                      state.TurnID,
+		Kind:                        string(state.Kind),
+		ReviewSkills:                state.ReviewSkills,
+		ReviewPrompt:                state.ReviewPrompt,
+		InvestigateRunID:            state.InvestigateRunID,
+		InvestigateTopic:            state.InvestigateTopic,
 		TranscriptIdentifierAtStart: state.TranscriptIdentifierAtStart,
 		CheckpointTranscriptStart:   state.CheckpointTranscriptStart,
 		TokenUsage:                  sessionData.TokenUsage,

cli/strategy/manual_commit_hooks_3.go

@@ -15,6 +15,8 @@ import (
 	"github.com/GrayCodeAI/trace/cli/interactive"
 	"github.com/GrayCodeAI/trace/cli/logging"
 	"github.com/GrayCodeAI/trace/cli/paths"
+	"github.com/GrayCodeAI/trace/cli/provenance"
+	"github.com/GrayCodeAI/trace/cli/review"
 	"github.com/GrayCodeAI/trace/cli/session"
 	"github.com/GrayCodeAI/trace/cli/settings"
 	"github.com/GrayCodeAI/trace/cli/trailers"
@@ -636,6 +638,28 @@ func addCheckpointTrailerWithComment(message string, checkpointID id.CheckpointI
 	return userContent + "\n\n" + trailer + "\n" + comment + "\n\n" + gitComments
 }
 
+func applyProvenanceEnvToState(state *SessionState) {
+	if os.Getenv(provenance.ReviewSession) != "" {
+		state.Kind = session.KindAgentReview
+		if skills, err := review.DecodeSkills(os.Getenv(provenance.ReviewSkills)); err == nil {
+			state.ReviewSkills = skills
+		}
+		if prompt := strings.TrimSpace(os.Getenv(provenance.ReviewPrompt)); prompt != "" {
+			state.ReviewPrompt = prompt
+		}
+	}
+
+	if os.Getenv(provenance.InvestigateSession) != "" {
+		state.Kind = session.KindAgentInvestigate
+		if runID := strings.TrimSpace(os.Getenv(provenance.InvestigateRunID)); provenance.IsValidRunID(runID) {
+			state.InvestigateRunID = runID
+		}
+		if topic := strings.TrimSpace(os.Getenv(provenance.InvestigateTopic)); topic != "" {
+			state.InvestigateTopic = topic
+		}
+	}
+}
+
 // InitializeSession creates session state for a new session or updates an existing one.
 // This implements the optional SessionInitializer interface.
 // Called during UserPromptSubmit to allow git hooks to detect active sessions.
@@ -698,6 +722,8 @@ func (s *ManualCommitStrategy) InitializeSession(ctx context.Context, sessionID
 			state.ModelName = model
 		}
 
+		applyProvenanceEnvToState(state)
+
 		// Update LastPrompt on every turn so condensation always has the current prompt
 		if userPrompt != "" {
 			state.LastPrompt = truncatePromptForStorage(userPrompt)
@@ -765,6 +791,8 @@ func (s *ManualCommitStrategy) InitializeSession(ctx context.Context, sessionID
 		return fmt.Errorf("failed to initialize session: %w", err)
 	}
 
+	applyProvenanceEnvToState(state)
+
 	// Apply phase transition: new session starts as ACTIVE.
 	if transErr := TransitionAndLog(ctx, state, session.EventTurnStart, session.TransitionContext{}, session.NoOpActionHandler{}); transErr != nil {
 		logging.Warn(logging.WithComponent(ctx, "hooks"), "turn start transition failed",

cmd/trace/main.go

@@ -0,0 +1,15 @@
+package main
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/GrayCodeAI/trace/cli"
+)
+
+func main() {
+	if err := cli.NewRootCmd().Execute(); err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+}