diff --git a/internal/config/config.go b/internal/config/config.go
index 09e2971..e3199e6 100644
--- a/internal/config/config.go
+++ b/internal/config/config.go
@@ -7,6 +7,7 @@ type Config struct {
 	Agent           string          `json:"agent"`
 	LogLevel        string          `json:"log_level"`
 	StrategyOptions StrategyOptions `json:"strategy_options"`
+	HookOptions     HookOptions     `json:"hook_options"`
 }
 
 // StrategyOptions holds strategy-specific options.
@@ -14,5 +15,12 @@ type StrategyOptions struct {
 	PushSessions bool `json:"push_sessions"`
 }
 
+// HookOptions holds hook-specific options.
+type HookOptions struct {
+	// SessionRetryTimeoutMs is the maximum time in milliseconds to retry
+	// reading session data in the post-commit hook. 0 disables retries.
+	SessionRetryTimeoutMs int `json:"session_retry_timeout_ms"`
+}
+
 // PartioDir is the directory name for partio config within a repo.
 const PartioDir = ".partio"
diff --git a/internal/config/defaults.go b/internal/config/defaults.go
index f06dde6..f85c408 100644
--- a/internal/config/defaults.go
+++ b/internal/config/defaults.go
@@ -10,5 +10,8 @@ func Defaults() Config {
 		StrategyOptions: StrategyOptions{
 			PushSessions: true,
 		},
+		HookOptions: HookOptions{
+			SessionRetryTimeoutMs: 3000,
+		},
 	}
 }
diff --git a/internal/config/env.go b/internal/config/env.go
index 090b142..040370f 100644
--- a/internal/config/env.go
+++ b/internal/config/env.go
@@ -2,6 +2,7 @@ package config
 
 import (
 	"os"
+	"strconv"
 	"strings"
 )
 
@@ -15,4 +16,9 @@ func applyEnv(cfg *Config) {
 	if v := os.Getenv("PARTIO_LOG_LEVEL"); v != "" {
 		cfg.LogLevel = v
 	}
+	if v := os.Getenv("PARTIO_SESSION_RETRY_TIMEOUT_MS"); v != "" {
+		if n, err := strconv.Atoi(v); err == nil {
+			cfg.HookOptions.SessionRetryTimeoutMs = n
+		}
+	}
 }
diff --git a/internal/hooks/postcommit.go b/internal/hooks/postcommit.go
index 0cd65b1..b54e6fa 100644
--- a/internal/hooks/postcommit.go
+++ b/internal/hooks/postcommit.go
@@ -55,9 +55,9 @@ func runPostCommit(repoRoot string, cfg config.Config) error {
 		attr = &attribution.Result{AgentPercent: 100}
 	}
 
-	// Parse agent session data
-	detector := claude.New()
-	sessionPath, sessionData, err := detector.FindLatestSession(repoRoot)
+	// Parse agent session data, retrying if data is not yet flushed to disk.
+	retryTimeout := time.Duration(cfg.HookOptions.SessionRetryTimeoutMs) * time.Millisecond
+	sessionPath, sessionData, err := findSessionWithRetry(newSessionFinder(), repoRoot, retryTimeout)
 	if err != nil {
 		slog.Warn("could not read agent session", "error", err)
 	}
diff --git a/internal/hooks/retry_session.go b/internal/hooks/retry_session.go
new file mode 100644
index 0000000..7fec938
--- /dev/null
+++ b/internal/hooks/retry_session.go
@@ -0,0 +1,55 @@
+package hooks
+
+import (
+	"log/slog"
+	"time"
+
+	"github.com/partio-io/cli/internal/agent"
+	"github.com/partio-io/cli/internal/agent/claude"
+)
+
+const initialRetryBackoff = 100 * time.Millisecond
+
+// sessionFinder is a function that attempts to find a session.
+type sessionFinder func(repoRoot string) (string, *agent.SessionData, error)
+
+// sessionDataReady returns true when the session data is considered available.
+func sessionDataReady(data *agent.SessionData, err error) bool {
+	return err == nil && data != nil && data.SessionID != ""
+}
+
+// findSessionWithRetry calls finder repeatedly with exponential backoff until
+// session data is available or the timeout expires. If the timeout is <= 0 no
+// retries are performed.
+func findSessionWithRetry(finder sessionFinder, repoRoot string, timeout time.Duration) (string, *agent.SessionData, error) {
+	path, data, err := finder(repoRoot)
+	if sessionDataReady(data, err) || timeout <= 0 {
+		return path, data, err
+	}
+
+	deadline := time.Now().Add(timeout)
+	backoff := initialRetryBackoff
+
+	for time.Now().Before(deadline) {
+		sleep := backoff
+		if remaining := time.Until(deadline); sleep > remaining {
+			sleep = remaining
+		}
+		time.Sleep(sleep)
+		backoff *= 2
+
+		path, data, err = finder(repoRoot)
+		if sessionDataReady(data, err) {
+			return path, data, err
+		}
+	}
+
+	slog.Warn("session data not available after retry window", "timeout_ms", timeout.Milliseconds())
+	return path, data, err
+}
+
+// newSessionFinder wraps the claude detector's FindLatestSession.
+func newSessionFinder() sessionFinder {
+	d := claude.New()
+	return d.FindLatestSession
+}
diff --git a/internal/hooks/retry_session_test.go b/internal/hooks/retry_session_test.go
new file mode 100644
index 0000000..1a401dc
--- /dev/null
+++ b/internal/hooks/retry_session_test.go
@@ -0,0 +1,124 @@
+package hooks
+
+import (
+	"errors"
+	"testing"
+	"time"
+
+	"github.com/partio-io/cli/internal/agent"
+)
+
+func TestFindSessionWithRetry_SuccessFirstTry(t *testing.T) {
+	calls := 0
+	finder := func(repoRoot string) (string, *agent.SessionData, error) {
+		calls++
+		return "/path/session.jsonl", &agent.SessionData{SessionID: "abc123"}, nil
+	}
+
+	path, data, err := findSessionWithRetry(finder, "/repo", 3*time.Second)
+
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if path != "/path/session.jsonl" {
+		t.Errorf("unexpected path: %s", path)
+	}
+	if data.SessionID != "abc123" {
+		t.Errorf("unexpected session ID: %s", data.SessionID)
+	}
+	if calls != 1 {
+		t.Errorf("expected 1 call, got %d", calls)
+	}
+}
+
+func TestFindSessionWithRetry_SuccessAfterRetry(t *testing.T) {
+	calls := 0
+	finder := func(repoRoot string) (string, *agent.SessionData, error) {
+		calls++
+		if calls < 3 {
+			return "", nil, errors.New("not ready")
+		}
+		return "/path/session.jsonl", &agent.SessionData{SessionID: "abc123"}, nil
+	}
+
+	path, data, err := findSessionWithRetry(finder, "/repo", 5*time.Second)
+
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if data.SessionID != "abc123" {
+		t.Errorf("unexpected session ID: %s", data.SessionID)
+	}
+	if path != "/path/session.jsonl" {
+		t.Errorf("unexpected path: %s", path)
+	}
+	if calls < 3 {
+		t.Errorf("expected at least 3 calls, got %d", calls)
+	}
+}
+
+func TestFindSessionWithRetry_TimeoutExhausted(t *testing.T) {
+	calls := 0
+	finder := func(repoRoot string) (string, *agent.SessionData, error) {
+		calls++
+		return "", nil, errors.New("not ready")
+	}
+
+	start := time.Now()
+	_, _, err := findSessionWithRetry(finder, "/repo", 300*time.Millisecond)
+	elapsed := time.Since(start)
+
+	if err == nil {
+		t.Error("expected error after timeout")
+	}
+	if calls < 2 {
+		t.Errorf("expected retries, got %d calls", calls)
+	}
+	if elapsed < 290*time.Millisecond {
+		t.Errorf("returned too early: %v", elapsed)
+	}
+	if elapsed > 2*time.Second {
+		t.Errorf("took too long: %v", elapsed)
+	}
+}
+
+func TestFindSessionWithRetry_ZeroTimeout_NoRetry(t *testing.T) {
+	calls := 0
+	finder := func(repoRoot string) (string, *agent.SessionData, error) {
+		calls++
+		return "", nil, errors.New("not ready")
+	}
+
+	_, _, err := findSessionWithRetry(finder, "/repo", 0)
+
+	if err == nil {
+		t.Error("expected error")
+	}
+	if calls != 1 {
+		t.Errorf("expected exactly 1 call with zero timeout, got %d", calls)
+	}
+}
+
+func TestFindSessionWithRetry_EmptySessionID_Retries(t *testing.T) {
+	calls := 0
+	finder := func(repoRoot string) (string, *agent.SessionData, error) {
+		calls++
+		if calls < 2 {
+			// File found but no session ID yet (empty/not flushed)
+			return "/path/session.jsonl", &agent.SessionData{SessionID: ""}, nil
+		}
+		return "/path/session.jsonl", &agent.SessionData{SessionID: "abc123"}, nil
+	}
+
+	_, data, err := findSessionWithRetry(finder, "/repo", 5*time.Second)
+
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if data.SessionID != "abc123" {
+		t.Errorf("unexpected session ID: %s", data.SessionID)
+	}
+	if calls < 2 {
+		t.Errorf("expected at least 2 calls, got %d", calls)
+	}
+}