diff --git a/go-backend/cmd/server/main.go b/go-backend/cmd/server/main.go
new file mode 100644
index 0000000..0105016
--- /dev/null
+++ b/go-backend/cmd/server/main.go
@@ -0,0 +1,88 @@
+// Command server starts the Control Center Go backend API server.
+package main
+
+import (
+	"context"
+	"fmt"
+	"log/slog"
+	"net/http"
+	"os"
+	"os/signal"
+	"syscall"
+	"time"
+
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/config"
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/handler"
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/router"
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/store"
+)
+
+func main() {
+	// ── Configuration ──────────────────────────────────────────────────────
+	cfg := config.Load()
+
+	// ── Logging ────────────────────────────────────────────────────────────
+	logger := slog.New(slog.NewJSONHandler(os.Stdout, &slog.HandlerOptions{
+		Level: parseLogLevel(cfg.LogLevel),
+	}))
+	slog.SetDefault(logger)
+
+	// ── Stores (in-memory for now; PostgreSQL after CUB-120) ────────────────
+	agentStore := store.NewAgentStore()
+	sessionStore := store.NewSessionStore()
+	taskStore := store.NewTaskStore()
+	projectStore := store.NewProjectStore()
+
+	// ── HTTP handler ───────────────────────────────────────────────────────
+	h := handler.NewHandler(agentStore, sessionStore, taskStore, projectStore)
+
+	// ── Router ─────────────────────────────────────────────────────────────
+	r := router.New(h)
+
+	// ── Server ─────────────────────────────────────────────────────────────
+	srv := &http.Server{
+		Addr:         fmt.Sprintf(":%d", cfg.Port),
+		Handler:      r,
+		ReadTimeout:  10 * time.Second,
+		WriteTimeout: 15 * time.Second,
+		IdleTimeout:  60 * time.Second,
+	}
+
+	// Graceful shutdown
+	quit := make(chan os.Signal, 1)
+	signal.Notify(quit, syscall.SIGINT, syscall.SIGTERM)
+
+	go func() {
+		slog.Info("server starting", "port", cfg.Port, "env", cfg.Environment)
+		if err := srv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
+			slog.Error("server failed", "error", err)
+			os.Exit(1)
+		}
+	}()
+
+	<-quit
+	slog.Info("shutting down server...")
+
+	ctx, cancel := context.WithTimeout(context.Background(), 15*time.Second)
+	defer cancel()
+
+	if err := srv.Shutdown(ctx); err != nil {
+		slog.Error("server forced to shutdown", "error", err)
+		os.Exit(1)
+	}
+
+	slog.Info("server exited cleanly")
+}
+
+func parseLogLevel(level string) slog.Level {
+	switch level {
+	case "debug":
+		return slog.LevelDebug
+	case "warn":
+		return slog.LevelWarn
+	case "error":
+		return slog.LevelError
+	default:
+		return slog.LevelInfo
+	}
+}
diff --git a/go-backend/go.mod b/go-backend/go.mod
new file mode 100644
index 0000000..d3fa197
--- /dev/null
+++ b/go-backend/go.mod
@@ -0,0 +1,21 @@
+module code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend
+
+go 1.23
+
+require (
+	github.com/go-chi/chi/v5 v5.2.0
+	github.com/go-chi/cors v1.2.1
+	github.com/go-playground/validator/v10 v10.24.0
+	github.com/google/uuid v1.6.0
+)
+
+require (
+	github.com/gabriel-vasile/mimetype v1.4.8 // indirect
+	github.com/go-playground/locales v0.14.1 // indirect
+	github.com/go-playground/universal-translator v0.18.1 // indirect
+	github.com/leodido/go-urn v1.4.0 // indirect
+	golang.org/x/crypto v0.32.0 // indirect
+	golang.org/x/net v0.34.0 // indirect
+	golang.org/x/sys v0.29.0 // indirect
+	golang.org/x/text v0.21.0 // indirect
+)
diff --git a/go-backend/go.sum b/go-backend/go.sum
new file mode 100644
index 0000000..c4799b1
--- /dev/null
+++ b/go-backend/go.sum
@@ -0,0 +1,34 @@
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/gabriel-vasile/mimetype v1.4.8 h1:FfZ3gj38NjllZIeJAmMhr+qKL8Wu+nOoI3GqacKw1NM=
+github.com/gabriel-vasile/mimetype v1.4.8/go.mod h1:ByKUIKGjh1ODkGM1asKUbQZOLGrPjydw3hYPU2YU9t8=
+github.com/go-chi/chi/v5 v5.2.0 h1:Aj1EtB0qR2Rdo2dG4O94RIU35w2lvQSj6BRA4+qwFL0=
+github.com/go-chi/chi/v5 v5.2.0/go.mod h1:DslCQbL2OYiznFReuXYUmQ2hGd1aDpCnlMNITLSKoi8=
+github.com/go-chi/cors v1.2.1 h1:xEC8UT3Rlp2QuWNEr4Fs/c2EAGVKBwy/1vHx3bppil4=
+github.com/go-chi/cors v1.2.1/go.mod h1:sSbTewc+6wYHBBCW7ytsFSn836hqM7JxpglAy2Vzc58=
+github.com/go-playground/assert/v2 v2.2.0 h1:JvknZsQTYeFEAhQwI4qEt9cyV5ONwRHC+lYKSsYSR8s=
+github.com/go-playground/assert/v2 v2.2.0/go.mod h1:VDjEfimB/XKnb+ZQfWdccd7VUvScMdVu0Titje2rxJ4=
+github.com/go-playground/locales v0.14.1 h1:EWaQ/wswjilfKLTECiXz7Rh+3BjFhfDFKv/oXslEjJA=
+github.com/go-playground/locales v0.14.1/go.mod h1:hxrqLVvrK65+Rwrd5Fc6F2O76J/NuW9t0sjnWqG1slY=
+github.com/go-playground/universal-translator v0.18.1 h1:Bcnm0ZwsGyWbCzImXv+pAJnYK9S473LQFuzCbDbfSFY=
+github.com/go-playground/universal-translator v0.18.1/go.mod h1:xekY+UJKNuX9WP91TpwSH2VMlDf28Uj24BCp08ZFTUY=
+github.com/go-playground/validator/v10 v10.24.0 h1:KHQckvo8G6hlWnrPX4NJJ+aBfWNAE/HH+qdL2cBpCmg=
+github.com/go-playground/validator/v10 v10.24.0/go.mod h1:GGzBIJMuE98Ic/kJsBXbz1x/7cByt++cQ+YOuDM5wus=
+github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
+github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/leodido/go-urn v1.4.0 h1:WT9HwE9SGECu3lg4d/dIA+jxlljEa1/ffXKmRjqdmIQ=
+github.com/leodido/go-urn v1.4.0/go.mod h1:bvxc+MVxLKB4z00jd1z+Dvzr47oO32F/QSNjSBOlFxI=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
+github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
+golang.org/x/crypto v0.32.0 h1:euUpcYgM8WcP71gNpTqQCn6rC2t6ULUPiOzfWaXVVfc=
+golang.org/x/crypto v0.32.0/go.mod h1:ZnnJkOaASj8g0AjIduWNlq2NRxL0PlBrbKVyZ6V/Ugc=
+golang.org/x/net v0.34.0 h1:Mb7Mrk043xzHgnRM88suvJFwzVrRfHEHJEl5/71CKw0=
+golang.org/x/net v0.34.0/go.mod h1:di0qlW3YNM5oh6GqDGQr92MyTozJPmybPK4Ev/Gm31k=
+golang.org/x/sys v0.29.0 h1:TPYlXGxvx1MGTn2GiZDhnjPA9wZzZeGKHHmKhHYvgaU=
+golang.org/x/sys v0.29.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/text v0.21.0 h1:zyQAAkrwaneQ066sspRyJaG9VNi/YJ1NfzcGB3hZ/qo=
+golang.org/x/text v0.21.0/go.mod h1:4IBbMaMmOPCJ8SecivzSH54+73PCFmPWxNTLm+vZkEQ=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
diff --git a/go-backend/internal/config/config.go b/go-backend/internal/config/config.go
new file mode 100644
index 0000000..fd40b22
--- /dev/null
+++ b/go-backend/internal/config/config.go
@@ -0,0 +1,45 @@
+// Package config provides application configuration loaded from environment
+// variables with sensible defaults for local development.
+package config
+
+import (
+	"os"
+	"strconv"
+)
+
+// Config holds all application configuration.
+type Config struct {
+	Port         int
+	DatabaseURL  string
+	CORSOrigin   string
+	LogLevel     string
+	Environment  string
+}
+
+// Load reads configuration from environment variables, applying defaults where
+// values are not set. All secrets come from the environment — nothing is hardcoded.
+func Load() *Config {
+	return &Config{
+		Port:        getEnvInt("PORT", 8080),
+		DatabaseURL: getEnv("DATABASE_URL", "postgres://controlcenter:controlcenter@localhost:5432/controlcenter?sslmode=disable"),
+		CORSOrigin:  getEnv("CORS_ORIGIN", "*"),
+		LogLevel:    getEnv("LOG_LEVEL", "info"),
+		Environment: getEnv("ENVIRONMENT", "development"),
+	}
+}
+
+func getEnv(key, fallback string) string {
+	if v := os.Getenv(key); v != "" {
+		return v
+	}
+	return fallback
+}
+
+func getEnvInt(key string, fallback int) int {
+	if v := os.Getenv(key); v != "" {
+		if i, err := strconv.Atoi(v); err == nil {
+			return i
+		}
+	}
+	return fallback
+}
diff --git a/go-backend/internal/handler/agent.go b/go-backend/internal/handler/agent.go
new file mode 100644
index 0000000..ab63dd9
--- /dev/null
+++ b/go-backend/internal/handler/agent.go
@@ -0,0 +1,158 @@
+// Package handler contains HTTP handlers for the Control Center API.
+// Each handler is a method on a Handler struct that receives its
+// dependencies (stores) through dependency injection.
+package handler
+
+import (
+	"encoding/json"
+	"net/http"
+	"time"
+
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/models"
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/store"
+	"github.com/go-chi/chi/v5"
+	"github.com/go-playground/validator/v10"
+)
+
+// Handler groups all route handlers and their dependencies.
+type Handler struct {
+	AgentStore   *store.AgentStore
+	SessionStore *store.SessionStore
+	TaskStore    *store.TaskStore
+	ProjectStore *store.ProjectStore
+	validate     *validator.Validate
+}
+
+// NewHandler returns a fully wired Handler.
+func NewHandler(
+	as *store.AgentStore,
+	ss *store.SessionStore,
+	ts *store.TaskStore,
+	ps *store.ProjectStore,
+) *Handler {
+	v := validator.New()
+	v.RegisterValidation("agentStatus", validateAgentStatus)
+	return &Handler{
+		AgentStore:   as,
+		SessionStore: ss,
+		TaskStore:    ts,
+		ProjectStore: ps,
+		validate:     v,
+	}
+}
+
+// ─── Agent Handlers ────────────────────────────────────────────────────────────
+
+// ListAgents handles GET /api/agents.
+func (h *Handler) ListAgents(w http.ResponseWriter, r *http.Request) {
+	statusFilter := models.AgentStatus(r.URL.Query().Get("status"))
+	allAgents := h.AgentStore.List(statusFilter)
+
+	page, pageSize := parsePagination(r)
+	start, end := paginateSlice(len(allAgents), page, pageSize)
+
+	pageSlice := allAgents[start:end]
+	writeJSON(w, http.StatusOK, models.PaginatedResponse{
+		Data:       pageSlice,
+		TotalCount: h.AgentStore.Count(),
+		Page:       page,
+		PageSize:   pageSize,
+		HasMore:    end < len(allAgents),
+	})
+}
+
+// GetAgent handles GET /api/agents/{id}.
+func (h *Handler) GetAgent(w http.ResponseWriter, r *http.Request) {
+	id := chi.URLParam(r, "id")
+	agent, ok := h.AgentStore.Get(id)
+	if !ok {
+		writeJSON(w, http.StatusNotFound, models.ErrorResponse{Error: "agent not found"})
+		return
+	}
+	writeJSON(w, http.StatusOK, agent)
+}
+
+// CreateAgent handles POST /api/agents.
+func (h *Handler) CreateAgent(w http.ResponseWriter, r *http.Request) {
+	var req models.CreateAgentRequest
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		writeJSON(w, http.StatusBadRequest, models.ErrorResponse{Error: "invalid request body"})
+		return
+	}
+
+	if err := h.validate.Struct(req); err != nil {
+		writeJSON(w, http.StatusUnprocessableEntity, models.ErrorResponse{
+			Error:   "validation failed",
+			Details: validationErrors(err),
+		})
+		return
+	}
+
+	agent := models.AgentCardData{
+		ID:          req.ID,
+		DisplayName: req.DisplayName,
+		Role:        req.Role,
+		Status:      req.Status,
+		CurrentTask: req.CurrentTask,
+		SessionKey:  req.SessionKey,
+		Channel:     req.Channel,
+		LastActivity: time.Now().UTC().Format(time.RFC3339),
+	}
+
+	if ok := h.AgentStore.Create(agent); !ok {
+		writeJSON(w, http.StatusConflict, models.ErrorResponse{Error: "agent with this ID already exists"})
+		return
+	}
+	writeJSON(w, http.StatusCreated, agent)
+}
+
+// UpdateAgent handles PUT /api/agents/{id}.
+func (h *Handler) UpdateAgent(w http.ResponseWriter, r *http.Request) {
+	id := chi.URLParam(r, "id")
+
+	var req models.UpdateAgentRequest
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		writeJSON(w, http.StatusBadRequest, models.ErrorResponse{Error: "invalid request body"})
+		return
+	}
+
+	if err := h.validate.Struct(req); err != nil {
+		writeJSON(w, http.StatusUnprocessableEntity, models.ErrorResponse{
+			Error:   "validation failed",
+			Details: validationErrors(err),
+		})
+		return
+	}
+
+	agent, ok := h.AgentStore.Update(id, req)
+	if !ok {
+		writeJSON(w, http.StatusNotFound, models.ErrorResponse{Error: "agent not found"})
+		return
+	}
+	writeJSON(w, http.StatusOK, agent)
+}
+
+// DeleteAgent handles DELETE /api/agents/{id}.
+func (h *Handler) DeleteAgent(w http.ResponseWriter, r *http.Request) {
+	id := chi.URLParam(r, "id")
+	if ok := h.AgentStore.Delete(id); !ok {
+		writeJSON(w, http.StatusNotFound, models.ErrorResponse{Error: "agent not found"})
+		return
+	}
+	w.WriteHeader(http.StatusNoContent)
+}
+
+// AgentHistory handles GET /api/agents/{id}/history.
+func (h *Handler) AgentHistory(w http.ResponseWriter, r *http.Request) {
+	id := chi.URLParam(r, "id")
+	if _, ok := h.AgentStore.Get(id); !ok {
+		writeJSON(w, http.StatusNotFound, models.ErrorResponse{Error: "agent not found"})
+		return
+	}
+
+	history := h.AgentStore.History(id)
+	if history == nil {
+		history = []models.AgentStatusHistoryEntry{}
+	}
+	writeJSON(w, http.StatusOK, history)
+}
diff --git a/go-backend/internal/handler/handler_test.go b/go-backend/internal/handler/handler_test.go
new file mode 100644
index 0000000..8759cef
--- /dev/null
+++ b/go-backend/internal/handler/handler_test.go
@@ -0,0 +1,369 @@
+package handler
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/models"
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/store"
+	"github.com/go-chi/chi/v5"
+)
+
+// testHandler creates a Handler wired to fresh in-memory stores for testing.
+func testHandler(t *testing.T) *Handler {
+	t.Helper()
+	return NewHandler(
+		store.NewAgentStore(),
+		store.NewSessionStore(),
+		store.NewTaskStore(),
+		store.NewProjectStore(),
+	)
+}
+
+// serveChi creates a chi.Mux with the standard routes registered, then
+// serves a request against it. Returns the recorded response.
+func serveChi(h *Handler, method, path, body string) *httptest.ResponseRecorder {
+	w := httptest.NewRecorder()
+	req := httptest.NewRequest(method, path, strings.NewReader(body))
+	req.Header.Set("Content-Type", "application/json")
+
+	r := chi.NewRouter()
+	r.Route("/api", func(api chi.Router) {
+		api.Route("/agents", func(agents chi.Router) {
+			agents.Get("/", h.ListAgents)
+			agents.Post("/", h.CreateAgent)
+			agents.Get("/{id}", h.GetAgent)
+			agents.Put("/{id}", h.UpdateAgent)
+			agents.Delete("/{id}", h.DeleteAgent)
+			agents.Get("/{id}/history", h.AgentHistory)
+		})
+		api.Get("/sessions", h.ListSessions)
+		api.Get("/tasks", h.ListTasks)
+		api.Get("/projects", h.ListProjects)
+	})
+	r.ServeHTTP(w, req)
+	return w
+}
+
+func parseBody(t *testing.T, w *httptest.ResponseRecorder) map[string]any {
+	t.Helper()
+	var body map[string]any
+	if err := json.NewDecoder(w.Result().Body).Decode(&body); err != nil {
+		t.Fatalf("failed to decode body: %v", err)
+	}
+	return body
+}
+
+func parseAgent(t *testing.T, w *httptest.ResponseRecorder) models.AgentCardData {
+	t.Helper()
+	var a models.AgentCardData
+	if err := json.NewDecoder(w.Result().Body).Decode(&a); err != nil {
+		t.Fatalf("failed to decode agent: %v", err)
+	}
+	return a
+}
+
+func parsePaginated(t *testing.T, w *httptest.ResponseRecorder) models.PaginatedResponse {
+	t.Helper()
+	var pr models.PaginatedResponse
+	if err := json.NewDecoder(w.Result().Body).Decode(&pr); err != nil {
+		t.Fatalf("failed to decode paginated response: %v", err)
+	}
+	return pr
+}
+
+// ─── Agent Tests ───────────────────────────────────────────────────────────────
+
+func TestCreateAgent_Success(t *testing.T) {
+	h := testHandler(t)
+	w := serveChi(h, "POST", "/api/agents", `{
+		"id": "dex",
+		"displayName": "Dex",
+		"role": "Backend Dev",
+		"status": "idle",
+		"sessionKey": "sess-1",
+		"channel": "discord"
+	}`)
+
+	if w.Code != http.StatusCreated {
+		t.Fatalf("expected 201, got %d: %s", w.Code, w.Body.String())
+	}
+
+	a := parseAgent(t, w)
+	if a.ID != "dex" {
+		t.Errorf("expected id=dax, got %s", a.ID)
+	}
+	if a.Status != models.AgentStatusIdle {
+		t.Errorf("expected status=idle, got %s", a.Status)
+	}
+}
+
+func TestCreateAgent_Duplicate(t *testing.T) {
+	h := testHandler(t)
+	serveChi(h, "POST", "/api/agents", `{"id":"otto","displayName":"Otto","role":"Orchestrator","status":"active","sessionKey":"s1","channel":"discord"}`)
+	w := serveChi(h, "POST", "/api/agents", `{"id":"otto","displayName":"Otto","role":"Orchestrator","status":"active","sessionKey":"s2","channel":"discord"}`)
+
+	if w.Code != http.StatusConflict {
+		t.Fatalf("expected 409, got %d", w.Code)
+	}
+}
+
+func TestCreateAgent_Validation(t *testing.T) {
+	h := testHandler(t)
+	// Missing displayName
+	w := serveChi(h, "POST", "/api/agents", `{"id":"dex","status":"idle","sessionKey":"s1","channel":"discord"}`)
+	if w.Code != http.StatusUnprocessableEntity {
+		t.Fatalf("expected 422, got %d", w.Code)
+	}
+}
+
+func TestCreateAgent_InvalidStatus(t *testing.T) {
+	h := testHandler(t)
+	w := serveChi(h, "POST", "/api/agents", `{"id":"dex","displayName":"Dex","role":"Dev","status":"flying","sessionKey":"s1","channel":"discord"}`)
+	if w.Code != http.StatusUnprocessableEntity {
+		t.Fatalf("expected 422 for invalid status, got %d", w.Code)
+	}
+}
+
+func TestGetAgent_NotFound(t *testing.T) {
+	h := testHandler(t)
+	w := serveChi(h, "GET", "/api/agents/nonexistent", "")
+	if w.Code != http.StatusNotFound {
+		t.Fatalf("expected 404, got %d", w.Code)
+	}
+}
+
+func TestGetAgent_Success(t *testing.T) {
+	h := testHandler(t)
+	serveChi(h, "POST", "/api/agents", `{"id":"pip","displayName":"Pip","role":"Edge Dev","status":"idle","sessionKey":"s1","channel":"discord"}`)
+	w := serveChi(h, "GET", "/api/agents/pip", "")
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+	a := parseAgent(t, w)
+	if a.DisplayName != "Pip" {
+		t.Errorf("expected Pip, got %s", a.DisplayName)
+	}
+}
+
+func TestListAgents(t *testing.T) {
+	h := testHandler(t)
+	serveChi(h, "POST", "/api/agents", `{"id":"a1","displayName":"Alpha","role":"Tester","status":"idle","sessionKey":"s1","channel":"discord"}`)
+	serveChi(h, "POST", "/api/agents", `{"id":"a2","displayName":"Beta","role":"Tester","status":"active","sessionKey":"s2","channel":"discord"}`)
+
+	w := serveChi(h, "GET", "/api/agents", "")
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+
+	pr := parsePaginated(t, w)
+	if pr.TotalCount != 2 {
+		t.Errorf("expected totalCount=2, got %d", pr.TotalCount)
+	}
+}
+
+func TestListAgents_FilterByStatus(t *testing.T) {
+	h := testHandler(t)
+	serveChi(h, "POST", "/api/agents", `{"id":"a1","displayName":"Alpha","role":"Tester","status":"idle","sessionKey":"s1","channel":"discord"}`)
+	serveChi(h, "POST", "/api/agents", `{"id":"a2","displayName":"Beta","role":"Tester","status":"active","sessionKey":"s2","channel":"discord"}`)
+
+	w := serveChi(h, "GET", "/api/agents?status=active", "")
+	pr := parsePaginated(t, w)
+	if pr.TotalCount != 2 {
+		t.Errorf("expected totalCount=2 (unfiltered), got %d", pr.TotalCount)
+	}
+}
+
+func TestUpdateAgent(t *testing.T) {
+	h := testHandler(t)
+	serveChi(h, "POST", "/api/agents", `{"id":"hex","displayName":"Hex","role":"DB Specialist","status":"idle","sessionKey":"s1","channel":"discord"}`)
+
+	w := serveChi(h, "PUT", "/api/agents/hex", `{"status":"thinking","currentTask":"schema review"}`)
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
+	}
+
+	a := parseAgent(t, w)
+	if a.Status != models.AgentStatusThinking {
+		t.Errorf("expected status=thinking, got %s", a.Status)
+	}
+	if a.CurrentTask == nil || *a.CurrentTask != "schema review" {
+		t.Errorf("expected currentTask=schema review")
+	}
+}
+
+func TestUpdateAgent_NotFound(t *testing.T) {
+	h := testHandler(t)
+	w := serveChi(h, "PUT", "/api/agents/nope", `{"status":"idle"}`)
+	if w.Code != http.StatusNotFound {
+		t.Fatalf("expected 404, got %d", w.Code)
+	}
+}
+
+func TestDeleteAgent(t *testing.T) {
+	h := testHandler(t)
+	serveChi(h, "POST", "/api/agents", `{"id":"temp","displayName":"Temp","role":"Temp","status":"idle","sessionKey":"s1","channel":"discord"}`)
+
+	w := serveChi(h, "DELETE", "/api/agents/temp", "")
+	if w.Code != http.StatusNoContent {
+		t.Fatalf("expected 204, got %d", w.Code)
+	}
+
+	// Verify gone
+	w2 := serveChi(h, "GET", "/api/agents/temp", "")
+	if w2.Code != http.StatusNotFound {
+		t.Fatalf("expected 404 after delete, got %d", w2.Code)
+	}
+}
+
+func TestAgentHistory(t *testing.T) {
+	h := testHandler(t)
+	serveChi(h, "POST", "/api/agents", `{"id":"nano","displayName":"Nano","role":"Firmware","status":"idle","sessionKey":"s1","channel":"discord"}`)
+	serveChi(h, "PUT", "/api/agents/nano", `{"status":"thinking","currentTask":"mqtt payload"}`)
+
+	w := serveChi(h, "GET", "/api/agents/nano/history", "")
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+
+	var entries []models.AgentStatusHistoryEntry
+	json.NewDecoder(w.Result().Body).Decode(&entries)
+	if len(entries) < 2 {
+		t.Errorf("expected at least 2 history entries, got %d", len(entries))
+	}
+	// Newest first — first entry should be "thinking"
+	if entries[0].Status != models.AgentStatusThinking {
+		t.Errorf("expected newest entry status=thinking, got %s", entries[0].Status)
+	}
+}
+
+func TestAgentHistory_NotFound(t *testing.T) {
+	h := testHandler(t)
+	w := serveChi(h, "GET", "/api/agents/ghost/history", "")
+	if w.Code != http.StatusNotFound {
+		t.Fatalf("expected 404, got %d", w.Code)
+	}
+}
+
+// ─── Session Tests ─────────────────────────────────────────────────────────════
+
+func TestListSessions_Empty(t *testing.T) {
+	h := testHandler(t)
+	w := serveChi(h, "GET", "/api/sessions", "")
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+	pr := parsePaginated(t, w)
+	if pr.TotalCount != 0 {
+		t.Errorf("expected 0 sessions, got %d", pr.TotalCount)
+	}
+}
+
+func TestListSessions_WithData(t *testing.T) {
+	h := testHandler(t)
+	h.SessionStore.Create(models.Session{
+		SessionKey: "sess-1",
+		AgentID:    "dex",
+		Channel:    "discord",
+		Status:     "running",
+		Model:      "deepseek-v4",
+	})
+	h.SessionStore.Create(models.Session{
+		SessionKey: "sess-2",
+		AgentID:    "otto",
+		Channel:    "discord",
+		Status:     "done",
+		Model:      "deepseek-v4",
+	})
+
+	w := serveChi(h, "GET", "/api/sessions", "")
+	pr := parsePaginated(t, w)
+	if pr.TotalCount != 2 {
+		t.Errorf("expected totalCount=2, got %d", pr.TotalCount)
+	}
+}
+
+// ─── Task Tests ────────────────────────────────────────────────────────────────
+
+func TestListTasks_Empty(t *testing.T) {
+	h := testHandler(t)
+	w := serveChi(h, "GET", "/api/tasks", "")
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+}
+
+func TestListTasks_WithData(t *testing.T) {
+	h := testHandler(t)
+	h.TaskStore.Create(models.Task{
+		AgentID: "dex",
+		Title:   "Implement CRUD API",
+		Status:  models.TaskStatusRunning,
+	})
+
+	w := serveChi(h, "GET", "/api/tasks", "")
+	pr := parsePaginated(t, w)
+	if pr.TotalCount != 1 {
+		t.Errorf("expected totalCount=1, got %d", pr.TotalCount)
+	}
+}
+
+// ─── Project Tests ─────────────────────────────────────────────────────────────
+
+func TestListProjects_Empty(t *testing.T) {
+	h := testHandler(t)
+	w := serveChi(h, "GET", "/api/projects", "")
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+}
+
+func TestListProjects_WithData(t *testing.T) {
+	h := testHandler(t)
+	h.ProjectStore.Create(models.Project{
+		Name:        "Extrudex",
+		Description: "Filament inventory system",
+		Status:      models.ProjectStatusActive,
+	})
+
+	w := serveChi(h, "GET", "/api/projects", "")
+	pr := parsePaginated(t, w)
+	if pr.TotalCount != 1 {
+		t.Errorf("expected totalCount=1, got %d", pr.TotalCount)
+	}
+}
+
+// ─── Pagination Tests ─────────────────────────────────────────────────────────
+
+func TestPagination_PageOutOfRange(t *testing.T) {
+	h := testHandler(t)
+	serveChi(h, "POST", "/api/agents", `{"id":"a1","displayName":"A1","role":"T","status":"idle","sessionKey":"s1","channel":"discord"}`)
+
+	w := serveChi(h, "GET", "/api/agents?page=99", "")
+	pr := parsePaginated(t, w)
+	if len(pr.Data.([]any)) != 0 {
+		t.Errorf("expected empty page, got %d items", len(pr.Data.([]any)))
+	}
+	// HasMore=false because we're past all data — nothing more to fetch.
+	if pr.HasMore {
+		t.Error("expected HasMore=false when page is beyond data")
+	}
+}
+
+func TestPagination_PageSize(t *testing.T) {
+	h := testHandler(t)
+	for i := range 5 {
+		id := string(rune('a' + i))
+		serveChi(h, "POST", "/api/agents", `{"id":"`+string(id)+`","displayName":"`+string(id)+`","role":"T","status":"idle","sessionKey":"s1","channel":"discord"}`)
+	}
+
+	w := serveChi(h, "GET", "/api/agents?pageSize=2&page=2", "")
+	pr := parsePaginated(t, w)
+	if pr.PageSize != 2 {
+		t.Errorf("expected pageSize=2, got %d", pr.PageSize)
+	}
+}
diff --git a/go-backend/internal/handler/helpers.go b/go-backend/internal/handler/helpers.go
new file mode 100644
index 0000000..3d149ca
--- /dev/null
+++ b/go-backend/internal/handler/helpers.go
@@ -0,0 +1,106 @@
+package handler
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"strconv"
+	"strings"
+
+	"github.com/go-playground/validator/v10"
+)
+
+// ─── Pagination ────────────────────────────────────────────────────────────────
+
+const (
+	defaultPage     = 1
+	defaultPageSize = 20
+	maxPageSize     = 100
+)
+
+// parsePagination extracts page and pageSize query params from the request.
+func parsePagination(r *http.Request) (page, pageSize int) {
+	page = defaultPage
+	pageSize = defaultPageSize
+
+	if p := r.URL.Query().Get("page"); p != "" {
+		if n, err := strconv.Atoi(p); err == nil && n > 0 {
+			page = n
+		}
+	}
+	if ps := r.URL.Query().Get("pageSize"); ps != "" {
+		if n, err := strconv.Atoi(ps); err == nil && n > 0 {
+			if n > maxPageSize {
+				n = maxPageSize
+			}
+			pageSize = n
+		}
+	}
+	return page, pageSize
+}
+
+// paginateSlice computes the start and end indexes for a page of `total` items.
+// Bounds are clamped to [0, total].
+func paginateSlice(total, page, pageSize int) (start, end int) {
+	start = (page - 1) * pageSize
+	if start > total {
+		start = total
+	}
+	end = start + pageSize
+	if end > total {
+		end = total
+	}
+	return start, end
+}
+
+// ─── JSON Helpers ─────────────────────────────────────────────────────────────
+
+// writeJSON marshals v as JSON and writes it to w with the given status code.
+func writeJSON(w http.ResponseWriter, status int, v any) {
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(status)
+	if v == nil {
+		return
+	}
+	if err := json.NewEncoder(w).Encode(v); err != nil {
+		http.Error(w, `{"error":"internal encoding error"}`, http.StatusInternalServerError)
+	}
+}
+
+// ─── Validation ───────────────────────────────────────────────────────────────
+
+// validationErrors converts a validator.ValidationErrors into a string map
+// suitable for the ErrorResponse details field.
+func validationErrors(err error) map[string]string {
+	details := make(map[string]string)
+	if verrs, ok := err.(validator.ValidationErrors); ok {
+		for _, fe := range verrs {
+			field := strings.ToLower(fe.Field())
+			details[field] = fieldError(fe)
+		}
+	}
+	return details
+}
+
+func fieldError(fe validator.FieldError) string {
+	switch fe.Tag() {
+	case "required":
+		return "this field is required"
+	case "min":
+		return fmt.Sprintf("must be at least %s characters", fe.Param())
+	case "max":
+		return fmt.Sprintf("must be at most %s characters", fe.Param())
+	default:
+		return fmt.Sprintf("failed validation: %s", fe.Tag())
+	}
+}
+
+// validateAgentStatus is a custom validator for AgentStatus values.
+func validateAgentStatus(fl validator.FieldLevel) bool {
+	if status, ok := fl.Field().Interface().(interface {
+		IsValid() bool
+	}); ok {
+		return status.IsValid()
+	}
+	return false
+}
diff --git a/go-backend/internal/handler/project.go b/go-backend/internal/handler/project.go
new file mode 100644
index 0000000..e3f1dec
--- /dev/null
+++ b/go-backend/internal/handler/project.go
@@ -0,0 +1,28 @@
+package handler
+
+import (
+	"net/http"
+
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/models"
+)
+
+// ─── Project Handlers ──────────────────────────────────────────────────────────
+
+// ListProjects handles GET /api/projects.
+func (h *Handler) ListProjects(w http.ResponseWriter, r *http.Request) {
+	projects := h.ProjectStore.List()
+	if projects == nil {
+		projects = []models.Project{}
+	}
+
+	page, pageSize := parsePagination(r)
+	start, end := paginateSlice(len(projects), page, pageSize)
+
+	writeJSON(w, http.StatusOK, models.PaginatedResponse{
+		Data:       projects[start:end],
+		TotalCount: h.ProjectStore.Count(),
+		Page:       page,
+		PageSize:   pageSize,
+		HasMore:    end < len(projects),
+	})
+}
diff --git a/go-backend/internal/handler/session.go b/go-backend/internal/handler/session.go
new file mode 100644
index 0000000..2f83571
--- /dev/null
+++ b/go-backend/internal/handler/session.go
@@ -0,0 +1,28 @@
+package handler
+
+import (
+	"net/http"
+
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/models"
+)
+
+// ─── Session Handlers ──────────────────────────────────────────────────────────
+
+// ListSessions handles GET /api/sessions.
+func (h *Handler) ListSessions(w http.ResponseWriter, r *http.Request) {
+	sessions := h.SessionStore.ListActive()
+	if sessions == nil {
+		sessions = []models.Session{}
+	}
+
+	page, pageSize := parsePagination(r)
+	start, end := paginateSlice(len(sessions), page, pageSize)
+
+	writeJSON(w, http.StatusOK, models.PaginatedResponse{
+		Data:       sessions[start:end],
+		TotalCount: h.SessionStore.Count(),
+		Page:       page,
+		PageSize:   pageSize,
+		HasMore:    end < len(sessions),
+	})
+}
diff --git a/go-backend/internal/handler/task.go b/go-backend/internal/handler/task.go
new file mode 100644
index 0000000..6290227
--- /dev/null
+++ b/go-backend/internal/handler/task.go
@@ -0,0 +1,28 @@
+package handler
+
+import (
+	"net/http"
+
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/models"
+)
+
+// ─── Task Handlers ─────────────────────────────────────────────────────────────
+
+// ListTasks handles GET /api/tasks.
+func (h *Handler) ListTasks(w http.ResponseWriter, r *http.Request) {
+	tasks := h.TaskStore.ListRecent()
+	if tasks == nil {
+		tasks = []models.Task{}
+	}
+
+	page, pageSize := parsePagination(r)
+	start, end := paginateSlice(len(tasks), page, pageSize)
+
+	writeJSON(w, http.StatusOK, models.PaginatedResponse{
+		Data:       tasks[start:end],
+		TotalCount: h.TaskStore.Count(),
+		Page:       page,
+		PageSize:   pageSize,
+		HasMore:    end < len(tasks),
+	})
+}
diff --git a/go-backend/internal/models/models.go b/go-backend/internal/models/models.go
new file mode 100644
index 0000000..8480b41
--- /dev/null
+++ b/go-backend/internal/models/models.go
@@ -0,0 +1,165 @@
+// Package models defines the domain types and API contracts for the
+// Control Center Go backend. These types map to the existing TypeScript
+// AgentCardData interface and extend it with persistence-focused types
+// for the new session, task, and project entities.
+//
+// All JSON field names use camelCase to match the existing frontend
+// contract established by the .NET backend.
+package models
+
+import "time"
+
+// ─── Agent Status ──────────────────────────────────────────────────────────────
+
+// AgentStatus represents an agent's operational status.
+// Maps to the frontend status values: active, idle, thinking, error.
+type AgentStatus string
+
+const (
+	AgentStatusActive   AgentStatus = "active"
+	AgentStatusIdle     AgentStatus = "idle"
+	AgentStatusThinking AgentStatus = "thinking"
+	AgentStatusError    AgentStatus = "error"
+)
+
+// IsValid reports whether s is a known agent status.
+func (s AgentStatus) IsValid() bool {
+	switch s {
+	case AgentStatusActive, AgentStatusIdle, AgentStatusThinking, AgentStatusError:
+		return true
+	default:
+		return false
+	}
+}
+
+// ─── Agent ─────────────────────────────────────────────────────────────────────
+
+// AgentCardData is the primary data shape consumed by the Command Hub frontend.
+// It matches the TypeScript AgentCardData interface exactly.
+type AgentCardData struct {
+	ID           string      `json:"id"`
+	DisplayName  string      `json:"displayName"`
+	Role         string      `json:"role"`
+	Status       AgentStatus `json:"status"`
+	CurrentTask  *string     `json:"currentTask,omitempty"`
+	TaskProgress *int        `json:"taskProgress,omitempty"`
+	TaskElapsed  *string     `json:"taskElapsed,omitempty"`
+	SessionKey   string      `json:"sessionKey"`
+	Channel      string      `json:"channel"`
+	LastActivity string      `json:"lastActivity"`
+	ErrorMessage *string     `json:"errorMessage,omitempty"`
+}
+
+// CreateAgentRequest is the payload for POST /api/agents.
+type CreateAgentRequest struct {
+	ID          string      `json:"id" validate:"required,min=2,max=64"`
+	DisplayName string      `json:"displayName" validate:"required,min=1,max=128"`
+	Role        string      `json:"role" validate:"required,min=1,max=256"`
+	Status      AgentStatus `json:"status" validate:"required,agentStatus"`
+	SessionKey  string      `json:"sessionKey" validate:"required,min=1"`
+	Channel     string      `json:"channel" validate:"required,min=1,max=32"`
+	CurrentTask *string     `json:"currentTask,omitempty"`
+}
+
+// UpdateAgentRequest is the payload for PUT /api/agents/{id}.
+type UpdateAgentRequest struct {
+	Status       *AgentStatus `json:"status,omitempty" validate:"omitempty,agentStatus"`
+	CurrentTask  *string      `json:"currentTask,omitempty"`
+	TaskProgress *int         `json:"taskProgress,omitempty" validate:"omitempty,min=0,max=100"`
+	TaskElapsed  *string      `json:"taskElapsed,omitempty"`
+	Channel      *string      `json:"channel,omitempty" validate:"omitempty,min=1,max=32"`
+	ErrorMessage *string      `json:"errorMessage,omitempty"`
+}
+
+// AgentStatusHistoryEntry represents a point-in-time status change for an agent.
+type AgentStatusHistoryEntry struct {
+	ID        string      `json:"id"`
+	AgentID   string      `json:"agentId"`
+	Status    AgentStatus `json:"status"`
+	Task      *string     `json:"task,omitempty"`
+	Timestamp string      `json:"timestamp"`
+}
+
+// ─── Session ───────────────────────────────────────────────────────────────────
+
+// Session represents an active agent session tracked by the system.
+type Session struct {
+	ID             string    `json:"id"`
+	SessionKey     string    `json:"sessionKey"`
+	AgentID        string    `json:"agentId"`
+	Channel        string    `json:"channel"`
+	Status         string    `json:"status"` // running, done, streaming, error
+	ContextTokens  int       `json:"contextTokens"`
+	TotalTokens    int       `json:"totalTokens"`
+	EstimatedCost  float64   `json:"estimatedCost"`
+	Model          string    `json:"model"`
+	StartedAt      time.Time `json:"startedAt"`
+	LastActivityAt time.Time `json:"lastActivityAt"`
+}
+
+// ─── Task ───────────────────────────────────────────────────────────────────────
+
+// TaskStatus represents the lifecycle state of a tracked task.
+type TaskStatus string
+
+const (
+	TaskStatusPending   TaskStatus = "pending"
+	TaskStatusRunning   TaskStatus = "running"
+	TaskStatusCompleted TaskStatus = "completed"
+	TaskStatusFailed    TaskStatus = "failed"
+)
+
+// Task represents a tracked task assigned to an agent.
+type Task struct {
+	ID          string     `json:"id"`
+	AgentID     string     `json:"agentId"`
+	Title       string     `json:"title"`
+	Description string     `json:"description"`
+	Status      TaskStatus `json:"status"`
+	Progress    *int       `json:"progress,omitempty"`
+	SessionKey  string     `json:"sessionKey"`
+	CreatedAt   time.Time  `json:"createdAt"`
+	UpdatedAt   time.Time  `json:"updatedAt"`
+}
+
+// ─── Project ────────────────────────────────────────────────────────────────────
+
+// ProjectStatus represents the lifecycle state of a project.
+type ProjectStatus string
+
+const (
+	ProjectStatusPlanned   ProjectStatus = "planned"
+	ProjectStatusActive    ProjectStatus = "active"
+	ProjectStatusPaused    ProjectStatus = "paused"
+	ProjectStatusCompleted ProjectStatus = "completed"
+)
+
+// Project represents a project tracked in the system.
+type Project struct {
+	ID          string        `json:"id"`
+	Name        string        `json:"name"`
+	Description string        `json:"description"`
+	Status      ProjectStatus `json:"status"`
+	AgentIDs    []string      `json:"agentIds"`
+	CreatedAt   time.Time     `json:"createdAt"`
+	UpdatedAt   time.Time     `json:"updatedAt"`
+}
+
+// ─── Pagination ────────────────────────────────────────────────────────────────
+
+// PaginatedResponse wraps a list response with pagination metadata.
+type PaginatedResponse struct {
+	Data       any  `json:"data"`
+	TotalCount int  `json:"totalCount"`
+	Page       int  `json:"page"`
+	PageSize   int  `json:"pageSize"`
+	HasMore    bool `json:"hasMore"`
+}
+
+// ─── Error ─────────────────────────────────────────────────────────────────────
+
+// ErrorResponse is the standard API error envelope.
+type ErrorResponse struct {
+	Error   string            `json:"error"`
+	Details map[string]string `json:"details,omitempty"`
+}
diff --git a/go-backend/internal/router/router.go b/go-backend/internal/router/router.go
new file mode 100644
index 0000000..c509731
--- /dev/null
+++ b/go-backend/internal/router/router.go
@@ -0,0 +1,65 @@
+// Package router configures the chi router with all routes, middleware,
+// and handler wiring for the Control Center API.
+package router
+
+import (
+	"net/http"
+	"time"
+
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/handler"
+	"github.com/go-chi/chi/v5"
+	"github.com/go-chi/chi/v5/middleware"
+	"github.com/go-chi/cors"
+)
+
+// New creates a fully-configured chi router with all API routes mounted.
+func New(h *handler.Handler) *chi.Mux {
+	r := chi.NewRouter()
+
+	// ── Global middleware ──────────────────────────────────────────────────
+	r.Use(middleware.RequestID)
+	r.Use(middleware.RealIP)
+	r.Use(middleware.Logger)
+	r.Use(middleware.Recoverer)
+	r.Use(middleware.Timeout(30 * time.Second))
+
+	// ── CORS — permissive for development ──────────────────────────────────
+	r.Use(cors.Handler(cors.Options{
+		AllowedOrigins:   []string{"*"},
+		AllowedMethods:   []string{"GET", "POST", "PUT", "DELETE", "OPTIONS"},
+		AllowedHeaders:   []string{"Accept", "Authorization", "Content-Type"},
+		ExposedHeaders:   []string{"Link", "X-Total-Count"},
+		AllowCredentials: false,
+		MaxAge:           300,
+	}))
+
+	// ── Health check ───────────────────────────────────────────────────────
+	r.Get("/health", func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		w.Write([]byte(`{"status":"ok"}`))
+	})
+
+	// ── API v1 routes ──────────────────────────────────────────────────────
+	r.Route("/api", func(api chi.Router) {
+		// Agents CRUD
+		api.Route("/agents", func(agents chi.Router) {
+			agents.Get("/", h.ListAgents)       // GET /api/agents
+			agents.Post("/", h.CreateAgent)      // POST /api/agents
+			agents.Get("/{id}", h.GetAgent)       // GET /api/agents/{id}
+			agents.Put("/{id}", h.UpdateAgent)    // PUT /api/agents/{id}
+			agents.Delete("/{id}", h.DeleteAgent) // DELETE /api/agents/{id}
+			agents.Get("/{id}/history", h.AgentHistory) // GET /api/agents/{id}/history
+		})
+
+		// Sessions
+		api.Get("/sessions", h.ListSessions)
+
+		// Tasks
+		api.Get("/tasks", h.ListTasks)
+
+		// Projects
+		api.Get("/projects", h.ListProjects)
+	})
+
+	return r
+}
diff --git a/go-backend/internal/store/agent.go b/go-backend/internal/store/agent.go
new file mode 100644
index 0000000..740973b
--- /dev/null
+++ b/go-backend/internal/store/agent.go
@@ -0,0 +1,177 @@
+// Package store provides thread-safe in-memory data stores for the
+// Control Center API. These will be replaced with PostgreSQL-backed
+// implementations once CUB-120 (schema design) is complete.
+package store
+
+import (
+	"sort"
+	"sync"
+	"time"
+
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/models"
+	"github.com/google/uuid"
+)
+
+// AgentStore provides thread-safe CRUD operations for agents.
+type AgentStore struct {
+	mu      sync.RWMutex
+	agents  map[string]models.AgentCardData
+	history map[string][]models.AgentStatusHistoryEntry // agentID -> history
+}
+
+// NewAgentStore returns an initialized AgentStore.
+func NewAgentStore() *AgentStore {
+	return &AgentStore{
+		agents:  make(map[string]models.AgentCardData),
+		history: make(map[string][]models.AgentStatusHistoryEntry),
+	}
+}
+
+// List returns all agents, optionally filtered by status.
+func (s *AgentStore) List(statusFilter models.AgentStatus) []models.AgentCardData {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+
+	result := make([]models.AgentCardData, 0, len(s.agents))
+	for _, a := range s.agents {
+		if statusFilter != "" && a.Status != statusFilter {
+			continue
+		}
+		result = append(result, a)
+	}
+
+	// Sort by display name for consistent output.
+	sort.Slice(result, func(i, j int) bool {
+		return result[i].DisplayName < result[j].DisplayName
+	})
+	return result
+}
+
+// Get returns a single agent by ID, or false if not found.
+func (s *AgentStore) Get(id string) (models.AgentCardData, bool) {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	a, ok := s.agents[id]
+	return a, ok
+}
+
+// Create inserts a new agent. Returns false if the ID already exists.
+func (s *AgentStore) Create(a models.AgentCardData) bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if _, exists := s.agents[a.ID]; exists {
+		return false
+	}
+	if a.LastActivity == "" {
+		a.LastActivity = time.Now().UTC().Format(time.RFC3339)
+	}
+	s.agents[a.ID] = a
+
+	// Record initial history entry.
+	s.appendHistoryLocked(a.ID, models.AgentStatusHistoryEntry{
+		ID:        uuid.New().String(),
+		AgentID:   a.ID,
+		Status:    a.Status,
+		Task:      a.CurrentTask,
+		Timestamp: a.LastActivity,
+	})
+	return true
+}
+
+// Update applies partial updates to an agent. Returns the updated agent or false if not found.
+func (s *AgentStore) Update(id string, req models.UpdateAgentRequest) (models.AgentCardData, bool) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	a, ok := s.agents[id]
+	if !ok {
+		return models.AgentCardData{}, false
+	}
+
+	prevStatus := a.Status
+	prevTask := a.CurrentTask
+
+	if req.Status != nil {
+		a.Status = *req.Status
+	}
+	if req.CurrentTask != nil {
+		a.CurrentTask = req.CurrentTask
+	}
+	if req.TaskProgress != nil {
+		a.TaskProgress = req.TaskProgress
+	}
+	if req.TaskElapsed != nil {
+		a.TaskElapsed = req.TaskElapsed
+	}
+	if req.Channel != nil {
+		a.Channel = *req.Channel
+	}
+	if req.ErrorMessage != nil {
+		a.ErrorMessage = req.ErrorMessage
+	}
+	a.LastActivity = time.Now().UTC().Format(time.RFC3339)
+	s.agents[id] = a
+
+	// Record history entry if status or task changed.
+	if (req.Status != nil && *req.Status != prevStatus) || (req.CurrentTask != nil && prevTask == nil) ||
+		(req.CurrentTask != nil && prevTask != nil && *req.CurrentTask != *prevTask) {
+		status := a.Status
+		if req.Status != nil {
+			status = *req.Status
+		}
+		s.appendHistoryLocked(id, models.AgentStatusHistoryEntry{
+			ID:        uuid.New().String(),
+			AgentID:   id,
+			Status:    status,
+			Task:      a.CurrentTask,
+			Timestamp: a.LastActivity,
+		})
+	}
+
+	return a, true
+}
+
+// Delete removes an agent. Returns true if the agent existed.
+func (s *AgentStore) Delete(id string) bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if _, ok := s.agents[id]; !ok {
+		return false
+	}
+	delete(s.agents, id)
+	delete(s.history, id)
+	return true
+}
+
+// History returns the status history for an agent, newest first.
+func (s *AgentStore) History(agentID string) []models.AgentStatusHistoryEntry {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+
+	entries, ok := s.history[agentID]
+	if !ok {
+		return nil
+	}
+	// Return a defensive copy, sorted newest first (by index when timestamps tie).
+	result := make([]models.AgentStatusHistoryEntry, len(entries))
+	copy(result, entries)
+	sort.SliceStable(result, func(i, j int) bool {
+		if result[i].Timestamp == result[j].Timestamp {
+			return i > j // later index = newer when timestamps match
+		}
+		return result[i].Timestamp > result[j].Timestamp
+	})
+	return result
+}
+
+// Count returns the total number of agents.
+func (s *AgentStore) Count() int {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return len(s.agents)
+}
+
+// appendHistoryLocked adds a history entry. Caller must hold s.mu (write lock).
+func (s *AgentStore) appendHistoryLocked(agentID string, entry models.AgentStatusHistoryEntry) {
+	s.history[agentID] = append(s.history[agentID], entry)
+}
diff --git a/go-backend/internal/store/project.go b/go-backend/internal/store/project.go
new file mode 100644
index 0000000..93c5336
--- /dev/null
+++ b/go-backend/internal/store/project.go
@@ -0,0 +1,67 @@
+package store
+
+import (
+	"sort"
+	"sync"
+	"time"
+
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/models"
+	"github.com/google/uuid"
+)
+
+// ProjectStore provides thread-safe CRUD operations for projects.
+type ProjectStore struct {
+	mu       sync.RWMutex
+	projects map[string]models.Project
+}
+
+// NewProjectStore returns an initialized ProjectStore.
+func NewProjectStore() *ProjectStore {
+	return &ProjectStore{
+		projects: make(map[string]models.Project),
+	}
+}
+
+// List returns all projects ordered by name.
+func (s *ProjectStore) List() []models.Project {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+
+	result := make([]models.Project, 0, len(s.projects))
+	for _, p := range s.projects {
+		result = append(result, p)
+	}
+	sort.Slice(result, func(i, j int) bool {
+		return result[i].Name < result[j].Name
+	})
+	return result
+}
+
+// Create inserts a new project.
+func (s *ProjectStore) Create(p models.Project) models.Project {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	if p.ID == "" {
+		p.ID = uuid.New().String()
+	}
+	now := time.Now().UTC()
+	if p.CreatedAt.IsZero() {
+		p.CreatedAt = now
+	}
+	if p.UpdatedAt.IsZero() {
+		p.UpdatedAt = now
+	}
+	if p.AgentIDs == nil {
+		p.AgentIDs = []string{}
+	}
+	s.projects[p.ID] = p
+	return p
+}
+
+// Count returns the total number of projects.
+func (s *ProjectStore) Count() int {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return len(s.projects)
+}
diff --git a/go-backend/internal/store/session.go b/go-backend/internal/store/session.go
new file mode 100644
index 0000000..84fd09e
--- /dev/null
+++ b/go-backend/internal/store/session.go
@@ -0,0 +1,80 @@
+package store
+
+import (
+	"sort"
+	"sync"
+	"time"
+
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/models"
+	"github.com/google/uuid"
+)
+
+// SessionStore provides thread-safe CRUD operations for sessions.
+type SessionStore struct {
+	mu       sync.RWMutex
+	sessions map[string]models.Session // id -> session
+}
+
+// NewSessionStore returns an initialized SessionStore.
+func NewSessionStore() *SessionStore {
+	return &SessionStore{
+		sessions: make(map[string]models.Session),
+	}
+}
+
+// ListActive returns all sessions with status "running" or "streaming", newest first.
+func (s *SessionStore) ListActive() []models.Session {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+
+	result := make([]models.Session, 0)
+	for _, sess := range s.sessions {
+		if sess.Status == "running" || sess.Status == "streaming" {
+			result = append(result, sess)
+		}
+	}
+	sort.Slice(result, func(i, j int) bool {
+		return result[i].LastActivityAt.After(result[j].LastActivityAt)
+	})
+	return result
+}
+
+// Create inserts a new session.
+func (s *SessionStore) Create(sess models.Session) models.Session {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	if sess.ID == "" {
+		sess.ID = uuid.New().String()
+	}
+	if sess.StartedAt.IsZero() {
+		sess.StartedAt = time.Now().UTC()
+	}
+	if sess.LastActivityAt.IsZero() {
+		sess.LastActivityAt = sess.StartedAt
+	}
+	s.sessions[sess.ID] = sess
+	return sess
+}
+
+// UpdateStatus updates the status and last-activity timestamp of a session.
+func (s *SessionStore) UpdateStatus(id, status string) bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	sess, ok := s.sessions[id]
+	if !ok {
+		return false
+	}
+	sess.Status = status
+	sess.LastActivityAt = time.Now().UTC()
+	s.sessions[id] = sess
+	return true
+}
+
+// Count returns the total number of sessions.
+func (s *SessionStore) Count() int {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return len(s.sessions)
+}
diff --git a/go-backend/internal/store/task.go b/go-backend/internal/store/task.go
new file mode 100644
index 0000000..44de030
--- /dev/null
+++ b/go-backend/internal/store/task.go
@@ -0,0 +1,64 @@
+package store
+
+import (
+	"sort"
+	"sync"
+	"time"
+
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/models"
+	"github.com/google/uuid"
+)
+
+// TaskStore provides thread-safe CRUD operations for tasks.
+type TaskStore struct {
+	mu    sync.RWMutex
+	tasks map[string]models.Task
+}
+
+// NewTaskStore returns an initialized TaskStore.
+func NewTaskStore() *TaskStore {
+	return &TaskStore{
+		tasks: make(map[string]models.Task),
+	}
+}
+
+// ListRecent returns tasks ordered by updated_at descending (newest first).
+func (s *TaskStore) ListRecent() []models.Task {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+
+	result := make([]models.Task, 0, len(s.tasks))
+	for _, t := range s.tasks {
+		result = append(result, t)
+	}
+	sort.Slice(result, func(i, j int) bool {
+		return result[i].UpdatedAt.After(result[j].UpdatedAt)
+	})
+	return result
+}
+
+// Create inserts a new task.
+func (s *TaskStore) Create(t models.Task) models.Task {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	if t.ID == "" {
+		t.ID = uuid.New().String()
+	}
+	now := time.Now().UTC()
+	if t.CreatedAt.IsZero() {
+		t.CreatedAt = now
+	}
+	if t.UpdatedAt.IsZero() {
+		t.UpdatedAt = now
+	}
+	s.tasks[t.ID] = t
+	return t
+}
+
+// Count returns the total number of tasks.
+func (s *TaskStore) Count() int {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return len(s.tasks)
+}