Add logging and fix /agents/ route error

Add hostname editing feature to agent detail page
- Create enhanced agent detail template with all stats and hostname edit form - Add UpdateHostname method to store for agent hostname updates - Add UpdateAgentHostname handler in UI for web form submissions - Add UpdateHostname endpoint in API handler for JSON requests - Register new POST /agents/{id}/hostname route for hostname updates - Improve agent detail page layout with Settings and Danger Zone sections - Add error handling for missing agents and empty hostname values
2025-12-20 07:34:02 +00:00 · 2025-12-20 06:51:27 +00:00
10 changed files with 263 additions and 69 deletions
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -1,42 +1,20 @@
 # Nerd Monitor - Agent Guidelines

 ## Build & Test Commands
+- **Generate templates**: `make templ`
+- **Build**: `make build` (server + agent) or `make build-server`/`make build-agent`
+- **Cross-platform**: `make build-all`
+- **Clean**: `make clean`
+- **Test all**: `go test ./...`
+- **Test single**: `go test -run TestName ./package`
+- **Format**: `gofmt -w ./cmd ./internal ./views`

-```bash
-# Generate Templ templates (required before building)
-make templ
-
-# Build server and agent for current OS
-make build
-
-# Build individual components
-make build-server
-make build-agent
-
-# Build for all platforms (Linux, macOS, Windows)
-make build-all
-
-# Clean build artifacts
-make clean
-```
-
-Note: This Go 1.21 project uses Templ for templating. Always run `make templ` before building.
+Note: Go 1.23+ project using Templ templating. Run `make templ` before building.

 ## Code Style Guidelines
-
-**Imports**: Standard library first, then third-party packages, then internal modules. Organize alphabetically within each group.
-
-**Formatting & Types**: Use `gofmt` standards. Explicit struct field comments for exported types. Prefer `error` return values (no panic for recoverable errors).
-
-**Naming**: CamelCase for exported symbols, lowercase for unexported. Receiver names as single letters (e.g., `(m *Manager)`). Constants use ALL_CAPS_SNAKE_CASE.
-
-**Error Handling**: Define sentinel errors in dedicated files (e.g., `auth/errors.go`). Check errors explicitly; use `http.Error(w, "message", status)` for HTTP responses. Wrap errors with context when needed.
-
-**Project Structure**: 
- `cmd/`: Executable entry points (server, agent)
- `internal/`: Packages (api, auth, stats, store, ui)
- `views/`: Templ templates (*.templ files)
-
-**Concurrency**: Use `sync.RWMutex` for shared state. Always defer lock releases. Keep critical sections small.
-
-**HTTP**: Use Chi router. Handlers follow `func (h *Handler) Name(w http.ResponseWriter, r *http.Request)`. Set Content-Type headers explicitly. Validate query parameters early and return 400/404 appropriately.
+- **Imports**: stdlib → third-party → internal (alphabetical within groups)
+- **Formatting**: `gofmt` standards, explicit exported struct comments
+- **Naming**: CamelCase exports, lowercase unexported, single-letter receivers (e.g., `(h *Handler)`)
+- **Error Handling**: Explicit checks, `http.Error()` for HTTP, contextual wrapping
+- **Concurrency**: `sync.RWMutex` for shared state, defer lock releases, small critical sections
+- **HTTP**: Chi router, `func (h *Handler) Method(w http.ResponseWriter, r *http.Request)`, set Content-Type, validate early
--- a/BIN
+++ b/BIN
--- a/cmd/agent/main.go
+++ b/cmd/agent/main.go
@@ -5,7 +5,7 @@ import (
 	"encoding/json"
 	"flag"
 	"fmt"
-	"log"
+	"log/slog"
 	"net/http"
 	"net/url"
 	"os"
@@ -25,8 +25,12 @@ func main() {
 	)
 	flag.Parse()

+	// Set up verbose logging
+	slog.SetLogLoggerLevel(slog.LevelDebug)
+
 	if *server == "" {
-		log.Fatal("--server flag is required")
+		slog.Error("Server flag is required")
+		os.Exit(1)
 	}

 	// Normalize server URL (add http:// if missing)
@@ -38,12 +42,13 @@ func main() {
 		var err error
 		id, err = generateAgentID()
 		if err != nil {
-			log.Fatalf("Failed to generate agent ID: %v", err)
+			slog.Error("Failed to generate agent ID", "error", err)
+			os.Exit(1)
 		}
 	}

-	log.Printf("Starting agent with ID: %s\n", id)
-	log.Printf("Reporting to: %s every %v\n", *server, *interval)
+	slog.Info("Starting agent", "id", id)
+	slog.Info("Reporting configuration", "server", *server, "interval", *interval)

 	// Initialize stats collector
 	collector := stats.NewCollector()
@@ -64,7 +69,7 @@ func main() {
 		case <-ticker.C:
 			reportStats(id, *server, collector)
 		case <-sigChan:
-			log.Println("Agent shutting down gracefully...")
+			slog.Info("Agent shutting down gracefully")
 			os.Exit(0)
 		}
 	}
@@ -79,37 +84,39 @@ func reportStats(agentID, serverURL string, collector *stats.Collector) {

 	stat, err := collector.Collect(hostname)
 	if err != nil {
-		log.Printf("Error collecting stats: %v", err)
+		slog.Error("Error collecting stats", "agentID", agentID, "hostname", hostname, "error", err)
 		return
 	}

 	// Marshal to JSON
 	body, err := json.Marshal(stat)
 	if err != nil {
-		log.Printf("Error marshaling stats: %v", err)
+		slog.Error("Error marshaling stats", "agentID", agentID, "error", err)
 		return
 	}

 	// Send to server
 	reportURL := fmt.Sprintf("%s/api/report?id=%s", serverURL, agentID)
+	slog.Debug("Sending stats report", "agentID", agentID, "url", reportURL, "bodySize", len(body))
 	resp, err := http.Post(reportURL, "application/json", bytes.NewReader(body))
 	if err != nil {
-		log.Printf("Error reporting stats: %v", err)
+		slog.Error("Error reporting stats", "agentID", agentID, "url", reportURL, "error", err)
 		return
 	}
 	defer resp.Body.Close()

 	if resp.StatusCode != http.StatusOK {
-		log.Printf("Server returned status %d", resp.StatusCode)
+		slog.Error("Server returned non-OK status", "agentID", agentID, "statusCode", resp.StatusCode, "url", reportURL)
 		return
 	}

-	log.Printf("Stats reported: CPU %.1f%% | RAM %s / %s | Disk %s / %s",
-		stat.CPUUsage,
-		formatBytes(stat.RAMUsage),
-		formatBytes(stat.RAMTotal),
-		formatBytes(stat.DiskUsage),
-		formatBytes(stat.DiskTotal),
+	slog.Debug("Stats reported successfully",
+		"agentID", agentID,
+		"cpu", stat.CPUUsage,
+		"ramUsage", formatBytes(stat.RAMUsage),
+		"ramTotal", formatBytes(stat.RAMTotal),
+		"diskUsage", formatBytes(stat.DiskUsage),
+		"diskTotal", formatBytes(stat.DiskTotal),
 	)
 }

--- a/cmd/server/main.go
+++ b/cmd/server/main.go
@@ -2,7 +2,7 @@ package main

 import (
 	"flag"
-	"log"
+	"log/slog"
 	"net/http"
 	"os"
 	"os/signal"
@@ -24,6 +24,9 @@ func main() {
 	)
 	flag.Parse()

+	// Set up verbose logging
+	slog.SetLogLoggerLevel(slog.LevelDebug)
+
 	// Initialize dependencies
 	s := store.New()
 	authMgr := auth.New(*username, *password)
@@ -45,6 +48,7 @@ func main() {
 		protectedRoutes.Use(authMgr.Middleware)
 		protectedRoutes.Get("/", uiHandler.Dashboard)
 		protectedRoutes.Get("/agents/{id}", uiHandler.AgentDetail)
+		protectedRoutes.Post("/agents/{id}/hostname", uiHandler.UpdateAgentHostname)
 		protectedRoutes.Post("/logout", uiHandler.Logout)
 		protectedRoutes.Post("/api/agents/remove-stale", uiHandler.RemoveStaleAgents)
 		protectedRoutes.Post("/api/agents/{id}/delete", uiHandler.DeleteAgent)
@@ -62,14 +66,15 @@ func main() {

 	go func() {
 		<-sigChan
-		log.Println("Shutting down server...")
+		slog.Info("Shutting down server...")
 		server.Close()
 		os.Exit(0)
 	}()

-	log.Printf("Starting server on http://%s:%s\n", *addr, *port)
-	log.Printf("Login with %s / %s\n", *username, *password)
+	slog.Info("Starting server", "addr", *addr+":"+*port, "url", "http://"+*addr+":"+*port)
+	slog.Info("Login credentials", "username", *username, "password", *password)
 	if err := server.ListenAndServe(); err != nil && err != http.ErrServerClosed {
-		log.Fatalf("Server error: %v", err)
+		slog.Error("Server error", "error", err)
+		os.Exit(1)
 	}
 }
--- a/internal/api/api.go
+++ b/internal/api/api.go
@@ -2,9 +2,12 @@ package api

 import (
 	"encoding/json"
+	"log/slog"
+	"net/http"
+
+	"github.com/go-chi/chi/v5"
 	"nerd-monitor/internal/stats"
 	"nerd-monitor/internal/store"
-	"net/http"
 )

 // Handler manages HTTP requests.
@@ -19,57 +22,115 @@ func New(s *store.Store) *Handler {

 // ReportStats handles agent stats reports.
 func (h *Handler) ReportStats(w http.ResponseWriter, r *http.Request) {
+	slog.Debug("Incoming stats report request", "method", r.Method, "path", r.URL.Path, "remoteAddr", r.RemoteAddr)
+
 	agentID := r.URL.Query().Get("id")
 	if agentID == "" {
+		slog.Warn("Missing agent ID in stats report", "remoteAddr", r.RemoteAddr)
 		http.Error(w, "missing agent id", http.StatusBadRequest)
 		return
 	}

 	var stat stats.Stats
 	if err := json.NewDecoder(r.Body).Decode(&stat); err != nil {
+		slog.Error("Invalid request body in stats report", "agentID", agentID, "error", err)
 		http.Error(w, "invalid request body", http.StatusBadRequest)
 		return
 	}

+	slog.Debug("Updating agent stats", "agentID", agentID, "hostname", stat.Hostname, "cpu", stat.CPUUsage)
 	h.store.UpdateAgent(agentID, &stat)
 	w.Header().Set("Content-Type", "application/json")
 	json.NewEncoder(w).Encode(map[string]string{"status": "ok"})
+	slog.Debug("Stats report processed successfully", "agentID", agentID)
 }

 // GetAgent returns stats for a single agent.
 func (h *Handler) GetAgent(w http.ResponseWriter, r *http.Request) {
+	slog.Debug("Incoming get agent request", "method", r.Method, "path", r.URL.Path, "remoteAddr", r.RemoteAddr)
+
 	agentID := r.URL.Query().Get("id")
 	if agentID == "" {
+		slog.Warn("Missing agent ID in get agent request", "remoteAddr", r.RemoteAddr)
 		http.Error(w, "missing agent id", http.StatusBadRequest)
 		return
 	}

+	slog.Debug("Retrieving agent stats", "agentID", agentID)
 	agent := h.store.GetAgent(agentID)
 	if agent == nil {
+		slog.Warn("Agent not found", "agentID", agentID)
 		http.Error(w, "agent not found", http.StatusNotFound)
 		return
 	}

 	w.Header().Set("Content-Type", "application/json")
 	json.NewEncoder(w).Encode(agent)
+	slog.Debug("Agent stats retrieved successfully", "agentID", agentID)
 }

 // ListAgents returns all agents.
 func (h *Handler) ListAgents(w http.ResponseWriter, r *http.Request) {
+	slog.Debug("Incoming list agents request", "method", r.Method, "path", r.URL.Path, "remoteAddr", r.RemoteAddr)
+
+	slog.Debug("Retrieving all agents")
 	agents := h.store.GetAllAgents()
 	w.Header().Set("Content-Type", "application/json")
 	json.NewEncoder(w).Encode(agents)
+	slog.Debug("All agents listed successfully", "count", len(agents))
 }

 // DeleteAgent removes an agent.
 func (h *Handler) DeleteAgent(w http.ResponseWriter, r *http.Request) {
+	slog.Debug("Incoming delete agent request", "method", r.Method, "path", r.URL.Path, "remoteAddr", r.RemoteAddr)
+
 	agentID := r.URL.Query().Get("id")
 	if agentID == "" {
+		slog.Warn("Missing agent ID in delete agent request", "remoteAddr", r.RemoteAddr)
 		http.Error(w, "missing agent id", http.StatusBadRequest)
 		return
 	}

+	slog.Info("Deleting agent", "agentID", agentID)
 	h.store.DeleteAgent(agentID)
 	w.Header().Set("Content-Type", "application/json")
 	json.NewEncoder(w).Encode(map[string]string{"status": "deleted"})
+	slog.Info("Agent deleted successfully", "agentID", agentID)
+}
+
+// UpdateHostname updates the hostname for an agent.
+func (h *Handler) UpdateHostname(w http.ResponseWriter, r *http.Request) {
+	slog.Debug("Incoming update hostname request", "method", r.Method, "path", r.URL.Path, "remoteAddr", r.RemoteAddr)
+
+	if r.Method != http.MethodPost {
+		slog.Warn("Invalid method for update hostname", "method", r.Method)
+		http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+
+	agentID := chi.URLParam(r, "id")
+	if agentID == "" {
+		slog.Warn("Missing agent ID in update hostname request", "remoteAddr", r.RemoteAddr)
+		http.Error(w, "missing agent id", http.StatusBadRequest)
+		return
+	}
+
+	hostname := r.FormValue("hostname")
+	if hostname == "" {
+		slog.Warn("Missing hostname in update request", "agentID", agentID)
+		http.Error(w, "missing hostname", http.StatusBadRequest)
+		return
+	}
+
+	slog.Info("Updating agent hostname", "agentID", agentID, "newHostname", hostname)
+	err := h.store.UpdateHostname(agentID, hostname)
+	if err != nil {
+		slog.Warn("Failed to update hostname - agent not found", "agentID", agentID, "error", err)
+		http.Error(w, "agent not found", http.StatusNotFound)
+		return
+	}
+
+	w.Header().Set("Content-Type", "application/json")
+	json.NewEncoder(w).Encode(map[string]string{"status": "updated"})
+	slog.Info("Agent hostname updated successfully", "agentID", agentID, "hostname", hostname)
 }
--- a/internal/auth/middleware.go
+++ b/internal/auth/middleware.go
@@ -3,6 +3,7 @@ package auth
 import (
 	"crypto/rand"
 	"encoding/hex"
+	"log/slog"
 	"net/http"
 	"sync"
 	"time"
@@ -36,11 +37,13 @@ func New(username, password string) *Manager {
 // Login validates credentials and creates a session.
 func (m *Manager) Login(username, password string) (string, error) {
 	if username != m.username || password != m.password {
+		slog.Debug("Login failed - invalid credentials", "username", username)
 		return "", ErrInvalidCredentials
 	}

 	token, err := generateToken()
 	if err != nil {
+		slog.Error("Failed to generate session token", "error", err)
 		return "", err
 	}

@@ -52,6 +55,7 @@ func (m *Manager) Login(username, password string) (string, error) {
 		ExpiresAt: time.Now().Add(m.expiryDur),
 	}

+	slog.Debug("Login successful, session created", "username", username, "token", token[:8]+"...")
 	return token, nil
 }

@@ -62,10 +66,17 @@ func (m *Manager) Validate(token string) bool {

 	session, ok := m.sessions[token]
 	if !ok {
+		slog.Debug("Session validation failed - token not found", "token", token[:8]+"...")
 		return false
 	}

-	return session.ExpiresAt.After(time.Now())
+	if !session.ExpiresAt.After(time.Now()) {
+		slog.Debug("Session validation failed - token expired", "token", token[:8]+"...", "expiredAt", session.ExpiresAt)
+		return false
+	}
+
+	slog.Debug("Session validation successful", "token", token[:8]+"...")
+	return true
 }

 // Logout invalidates a session.
@@ -74,16 +85,24 @@ func (m *Manager) Logout(token string) {
 	defer m.mu.Unlock()

 	delete(m.sessions, token)
+	slog.Debug("Session logged out", "token", token[:8]+"...")
 }

 // Middleware returns a Chi middleware for authentication.
 func (m *Manager) Middleware(next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		cookie, err := r.Cookie("session_token")
-		if err != nil || !m.Validate(cookie.Value) {
+		if err != nil {
+			slog.Debug("Authentication failed - no session cookie", "path", r.URL.Path, "remoteAddr", r.RemoteAddr)
 			http.Redirect(w, r, "/login", http.StatusSeeOther)
 			return
 		}
+		if !m.Validate(cookie.Value) {
+			slog.Debug("Authentication failed - invalid session", "path", r.URL.Path, "remoteAddr", r.RemoteAddr)
+			http.Redirect(w, r, "/login", http.StatusSeeOther)
+			return
+		}
+		slog.Debug("Authentication successful", "path", r.URL.Path, "remoteAddr", r.RemoteAddr)
 		next.ServeHTTP(w, r)
 	})
 }
--- a/internal/store/store.go
+++ b/internal/store/store.go
@@ -1,12 +1,19 @@
 package store

 import (
+	"errors"
+	"log/slog"
 	"sync"
 	"time"

 	"nerd-monitor/internal/stats"
 )

+var (
+	// ErrAgentNotFound is returned when an agent is not found.
+	ErrAgentNotFound = errors.New("agent not found")
+)
+
 // AgentStats represents the latest stats for an agent.
 type AgentStats struct {
 	ID        string
@@ -47,6 +54,7 @@ func (s *Store) UpdateAgent(id string, stat *stats.Stats) {
 		DiskTotal: stat.DiskTotal,
 		LastSeen:  time.Now(),
 	}
+	slog.Debug("Agent stats updated", "agentID", id, "hostname", stat.Hostname, "cpu", stat.CPUUsage)
 }

 // GetAgent retrieves agent stats by ID.
@@ -54,7 +62,13 @@ func (s *Store) GetAgent(id string) *AgentStats {
 	s.mu.RLock()
 	defer s.mu.RUnlock()

-	return s.agents[id]
+	agent := s.agents[id]
+	if agent != nil {
+		slog.Debug("Agent retrieved", "agentID", id, "hostname", agent.Hostname)
+	} else {
+		slog.Debug("Agent not found", "agentID", id)
+	}
+	return agent
 }

 // GetAllAgents returns all agents.
@@ -66,6 +80,7 @@ func (s *Store) GetAllAgents() []*AgentStats {
 	for _, agent := range s.agents {
 		agents = append(agents, agent)
 	}
+	slog.Debug("All agents retrieved", "count", len(agents))
 	return agents
 }

@@ -75,4 +90,21 @@ func (s *Store) DeleteAgent(id string) {
 	defer s.mu.Unlock()

 	delete(s.agents, id)
+	slog.Debug("Agent deleted", "agentID", id)
+}
+
+// UpdateHostname updates the hostname for an agent.
+func (s *Store) UpdateHostname(id string, hostname string) error {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	agent, exists := s.agents[id]
+	if !exists {
+		slog.Debug("Agent not found for hostname update", "agentID", id)
+		return ErrAgentNotFound
+	}
+
+	agent.Hostname = hostname
+	slog.Debug("Agent hostname updated", "agentID", id, "hostname", hostname)
+	return nil
 }
--- a/internal/ui/handlers.go
+++ b/internal/ui/handlers.go
@@ -2,9 +2,11 @@ package ui

 import (
 	"context"
+	"log/slog"
 	"net/http"
 	"time"

+	"github.com/go-chi/chi/v5"
 	"nerd-monitor/internal/auth"
 	"nerd-monitor/internal/store"
 	"nerd-monitor/views"
@@ -26,30 +28,42 @@ func New(s *store.Store, a *auth.Manager) *Handler {

 // Dashboard renders the dashboard page.
 func (h *Handler) Dashboard(w http.ResponseWriter, r *http.Request) {
+	slog.Debug("Incoming dashboard request", "method", r.Method, "path", r.URL.Path, "remoteAddr", r.RemoteAddr)
+
+	slog.Debug("Rendering dashboard", "agentCount", len(h.store.GetAllAgents()), "staleAgentCount", len(h.getStaleAgents()))
 	agents := h.store.GetAllAgents()
 	staleAgents := h.getStaleAgents()

 	component := views.Dashboard(agents, staleAgents)
 	component.Render(context.Background(), w)
+	slog.Debug("Dashboard rendered successfully")
 }

 // AgentDetail renders the agent detail page.
 func (h *Handler) AgentDetail(w http.ResponseWriter, r *http.Request) {
-	agentID := r.PathValue("id")
+	slog.Debug("Incoming agent detail request", "method", r.Method, "path", r.URL.Path, "remoteAddr", r.RemoteAddr)
+
+	agentID := chi.URLParam(r, "id")
+	slog.Debug("Retrieving agent detail", "agentID", agentID)
 	agent := h.store.GetAgent(agentID)

 	if agent == nil {
+		slog.Warn("Agent not found for detail view", "agentID", agentID)
 		http.NotFound(w, r)
 		return
 	}

 	component := views.AgentDetail(agent)
 	component.Render(context.Background(), w)
+	slog.Debug("Agent detail rendered successfully", "agentID", agentID)
 }

 // Login renders the login page.
 func (h *Handler) Login(w http.ResponseWriter, r *http.Request) {
+	slog.Debug("Incoming login request", "method", r.Method, "path", r.URL.Path, "remoteAddr", r.RemoteAddr)
+
 	if r.Method == http.MethodGet {
+		slog.Debug("Rendering login page")
 		component := views.LoginPage("")
 		component.Render(context.Background(), w)
 		return
@@ -59,13 +73,16 @@ func (h *Handler) Login(w http.ResponseWriter, r *http.Request) {
 		username := r.FormValue("username")
 		password := r.FormValue("password")

+		slog.Debug("Attempting login", "username", username, "remoteAddr", r.RemoteAddr)
 		token, err := h.auth.Login(username, password)
 		if err != nil {
+			slog.Warn("Login failed - invalid credentials", "username", username, "remoteAddr", r.RemoteAddr, "error", err)
 			component := views.LoginPage("Invalid credentials")
 			component.Render(context.Background(), w)
 			return
 		}

+		slog.Info("Login successful", "username", username, "remoteAddr", r.RemoteAddr)
 		http.SetCookie(w, &http.Cookie{
 			Name:     "session_token",
 			Value:    token,
@@ -79,19 +96,26 @@ func (h *Handler) Login(w http.ResponseWriter, r *http.Request) {
 		return
 	}

+	slog.Warn("Invalid method for login", "method", r.Method)
 	http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
 }

 // Logout handles logout.
 func (h *Handler) Logout(w http.ResponseWriter, r *http.Request) {
+	slog.Debug("Incoming logout request", "method", r.Method, "path", r.URL.Path, "remoteAddr", r.RemoteAddr)
+
 	if r.Method != http.MethodPost {
+		slog.Warn("Invalid method for logout", "method", r.Method)
 		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
 		return
 	}

 	cookie, err := r.Cookie("session_token")
 	if err == nil {
+		slog.Info("Logging out user", "remoteAddr", r.RemoteAddr)
 		h.auth.Logout(cookie.Value)
+	} else {
+		slog.Debug("Logout attempted without valid session", "remoteAddr", r.RemoteAddr)
 	}

 	http.SetCookie(w, &http.Cookie{
@@ -107,32 +131,73 @@ func (h *Handler) Logout(w http.ResponseWriter, r *http.Request) {

 // RemoveStaleAgents handles bulk removal of stale agents.
 func (h *Handler) RemoveStaleAgents(w http.ResponseWriter, r *http.Request) {
+	slog.Debug("Incoming remove stale agents request", "method", r.Method, "path", r.URL.Path, "remoteAddr", r.RemoteAddr)
+
 	if r.Method != http.MethodPost {
+		slog.Warn("Invalid method for remove stale agents", "method", r.Method)
 		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
 		return
 	}

 	agentIDs := r.Form["agent_ids"]
+	slog.Info("Removing stale agents", "count", len(agentIDs), "agentIDs", agentIDs)
 	for _, id := range agentIDs {
 		h.store.DeleteAgent(id)
 	}

+	slog.Info("Stale agents removed successfully", "count", len(agentIDs))
 	http.Redirect(w, r, "/", http.StatusSeeOther)
 }

 // DeleteAgent handles single agent deletion.
 func (h *Handler) DeleteAgent(w http.ResponseWriter, r *http.Request) {
+	slog.Debug("Incoming delete agent request", "method", r.Method, "path", r.URL.Path, "remoteAddr", r.RemoteAddr)
+
 	if r.Method != http.MethodPost {
+		slog.Warn("Invalid method for delete agent", "method", r.Method)
 		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
 		return
 	}

-	agentID := r.PathValue("id")
+	agentID := chi.URLParam(r, "id")
+	slog.Info("Deleting agent", "agentID", agentID)
 	h.store.DeleteAgent(agentID)

+	slog.Info("Agent deleted successfully", "agentID", agentID)
 	http.Redirect(w, r, "/", http.StatusSeeOther)
 }

+// UpdateAgentHostname handles hostname updates for agents.
+func (h *Handler) UpdateAgentHostname(w http.ResponseWriter, r *http.Request) {
+	slog.Debug("Incoming update agent hostname request", "method", r.Method, "path", r.URL.Path, "remoteAddr", r.RemoteAddr)
+
+	if r.Method != http.MethodPost {
+		slog.Warn("Invalid method for update agent hostname", "method", r.Method)
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+
+	agentID := chi.URLParam(r, "id")
+	hostname := r.FormValue("hostname")
+
+	if hostname == "" {
+		slog.Warn("Empty hostname provided for update", "agentID", agentID)
+		http.Error(w, "Hostname cannot be empty", http.StatusBadRequest)
+		return
+	}
+
+	slog.Info("Updating agent hostname", "agentID", agentID, "newHostname", hostname)
+	err := h.store.UpdateHostname(agentID, hostname)
+	if err != nil {
+		slog.Warn("Failed to update hostname - agent not found", "agentID", agentID, "error", err)
+		http.NotFound(w, r)
+		return
+	}
+
+	slog.Info("Agent hostname updated successfully", "agentID", agentID, "hostname", hostname)
+	http.Redirect(w, r, "/agents/"+agentID, http.StatusSeeOther)
+}
+
 // getStaleAgents returns agents that haven't reported in 6 months.
 func (h *Handler) getStaleAgents() []*store.AgentStats {
 	const staleThreshold = 6 * 30 * 24 * time.Hour
--- a/BIN
+++ b/BIN
--- a/views/agent_detail.templ
+++ b/views/agent_detail.templ
@@ -17,6 +17,7 @@ templ agentDetailContent(agent *store.AgentStats) {
 		@AgentStatusBadge(agent.LastSeen)
 	</div>
 	
+	<!-- CPU Usage Card -->
 	<div class="grid" style="grid-template-columns: 1fr;">
 		<div class="card">
 			<div class="card-title">CPU Usage</div>
@@ -32,6 +33,7 @@ templ agentDetailContent(agent *store.AgentStats) {
 		</div>
 	</div>
 	
+	<!-- Memory and Disk Usage Cards -->
 	<div class="grid" style="margin-top: 1.5rem;">
 		<div class="card">
 			<div class="card-title">Memory Usage</div>
@@ -43,24 +45,49 @@ templ agentDetailContent(agent *store.AgentStats) {
 		</div>
 	</div>
 	
+	<!-- Agent Information and Settings -->
 	<div class="card" style="margin-top: 1.5rem;">
 		<div class="card-title">Agent Information</div>
 		<div class="metric-row">
 			<span class="metric-label">Agent ID</span>
 			<span class="metric-value" style="font-family: monospace; font-size: 0.875rem;">{ agent.ID }</span>
 		</div>
-		<div class="metric-row">
-			<span class="metric-label">Hostname</span>
-			<span class="metric-value">{ agent.Hostname }</span>
-		</div>
 		<div class="metric-row">
 			<span class="metric-label">Last Seen</span>
 			<span class="metric-value">{ agent.LastSeen.Format("2006-01-02 15:04:05") }</span>
 		</div>
 	</div>
 	
-	<div class="btn-group" style="margin-top: 1.5rem;">
-		<form method="POST" action={ templ.SafeURL(fmt.Sprintf("/api/agents/%s/delete", agent.ID)) } style="margin: 0;" onsubmit="return confirm('Are you sure you want to remove this agent?');">
+	<!-- Hostname Settings -->
+	<div class="card" style="margin-top: 1.5rem;">
+		<div class="card-title">Settings</div>
+		<form method="POST" action={ templ.SafeURL(fmt.Sprintf("/agents/%s/hostname", agent.ID)) } style="display: flex; flex-direction: column; gap: 1rem;">
+			<div style="display: flex; flex-direction: column; gap: 0.5rem;">
+				<label for="hostname" style="font-size: 0.875rem; font-weight: 500; color: #cbd5e1;">
+					Hostname
+				</label>
+				<input 
+					type="text" 
+					id="hostname" 
+					name="hostname" 
+					value={ agent.Hostname }
+					required
+					style="padding: 0.5rem 0.75rem; background-color: #1e293b; border: 1px solid #475569; border-radius: 0.375rem; color: #e2e8f0; font-size: 0.875rem;"
+				/>
+			</div>
+			<button type="submit" class="btn btn-primary" style="align-self: flex-start;">
+				Update Hostname
+			</button>
+		</form>
+	</div>
+	
+	<!-- Danger Zone -->
+	<div class="card" style="margin-top: 1.5rem; border-left: 3px solid #ef4444;">
+		<div class="card-title" style="color: #ef4444;">Danger Zone</div>
+		<p style="margin: 0 0 1rem 0; color: #94a3b8; font-size: 0.875rem;">
+			Deleting this agent will remove all its data and history.
+		</p>
+		<form method="POST" action={ templ.SafeURL(fmt.Sprintf("/api/agents/%s/delete", agent.ID)) } style="margin: 0;" onsubmit="return confirm('Are you sure you want to remove this agent? This action cannot be undone.');">
 			<button type="submit" class="btn btn-danger">Delete Agent</button>
 		</form>
 	</div>