diff --git a/internal/cmd/dog.go b/internal/cmd/dog.go
index 9a8174c0..6c8cb147 100644
--- a/internal/cmd/dog.go
+++ b/internal/cmd/dog.go
@@ -808,7 +808,7 @@ func runDogDispatch(cmd *cobra.Command, args []string) error {
 
 	// Build startup command with initial prompt to check mail and execute plugin
 	initialPrompt := fmt.Sprintf("I am dog %s. Check my mail inbox with 'gt mail inbox' and execute the plugin instructions I received.", targetDog.Name)
-	startCmd := config.BuildAgentStartupCommand("dog", "", townRoot, targetDog.Path, initialPrompt)
+	startCmd := config.BuildDogStartupCommand(targetDog.Name, targetDog.Path, townRoot, initialPrompt)
 
 	// Create session from dog's directory
 	if err := t.NewSessionWithCommand(dogSessionName, targetDog.Path, startCmd); err != nil {
@@ -818,7 +818,9 @@ func runDogDispatch(cmd *cobra.Command, args []string) error {
 		// Non-fatal: mail was sent, dog is marked as working, but no session to execute
 		// The deacon or human can manually start the session later
 	} else {
-		// Set environment for the dog session
+		// Also set tmux environment as a fallback (belt and suspenders).
+		// The startup command exports these vars, but setting them in tmux
+		// environment ensures new panes/windows in the session inherit them.
 		envVars := config.AgentEnv(config.AgentEnvConfig{
 			Role:      "dog",
 			AgentName: targetDog.Name,
diff --git a/internal/cmd/mail_identity.go b/internal/cmd/mail_identity.go
index 70d087ba..2a2264a6 100644
--- a/internal/cmd/mail_identity.go
+++ b/internal/cmd/mail_identity.go
@@ -129,6 +129,14 @@ func detectSenderFromRole(role string) string {
 			return fmt.Sprintf("%s/refinery", rig)
 		}
 		return detectSenderFromCwd()
+	case "dog":
+		// Dogs use BD_ACTOR directly since they're town-level (no rig)
+		// Format: deacon/dogs/<name>
+		actor := os.Getenv("BD_ACTOR")
+		if actor != "" {
+			return actor
+		}
+		return detectSenderFromCwd()
 	default:
 		// Unknown role, try cwd detection
 		return detectSenderFromCwd()
diff --git a/internal/config/loader.go b/internal/config/loader.go
index 612f6cae..6ab24a18 100644
--- a/internal/config/loader.go
+++ b/internal/config/loader.go
@@ -1472,6 +1472,18 @@ func BuildCrewStartupCommandWithAgentOverride(rigName, crewName, rigPath, prompt
 	return BuildStartupCommandWithAgentOverride(envVars, rigPath, prompt, agentOverride)
 }
 
+// BuildDogStartupCommand builds the startup command for a deacon dog.
+// Dogs are town-level agents, so they don't have a rig.
+// Sets GT_ROLE=dog, BD_ACTOR=deacon/dogs/<name>, and GT_ROOT.
+func BuildDogStartupCommand(dogName, dogPath, townRoot, prompt string) string {
+	envVars := AgentEnv(AgentEnvConfig{
+		Role:      "dog",
+		AgentName: dogName,
+		TownRoot:  townRoot,
+	})
+	return BuildStartupCommand(envVars, dogPath, prompt)
+}
+
 // ExpectedPaneCommands returns tmux pane command names that indicate the runtime is running.
 // Claude can report as "node" (older versions) or "claude" (newer versions).
 // Other runtimes typically report their executable name.