feat: enhance AI model management in Discord bot

- Updated LLMClient interface to support model-specific generation and model listing.
- Integrated model store and validator into the command application for managing AI models.
- Implemented commands for setting, getting, and listing active AI models in Discord.
- Enhanced AI query handling to utilize the selected model and return model information in responses.
- Added caching mechanism for model validation to improve performance.
- Introduced gRPC methods for listing available AI models in the ai-gateway.
- Updated protobuf definitions to include model-related fields and messages.
- Added tests for model store and validator functionalities.

ai-gateway/cmd/gateway/main.go

@@ -67,7 +67,7 @@ func main() {
 		os.Exit(1)
 	}
 
-	ollamaClient := ollama.New(cfg.OllamaURL, cfg.OllamaModel, &http.Client{Timeout: cfg.OllamaTimeout})
+	ollamaClient := ollama.New(cfg.OllamaURL, &http.Client{Timeout: cfg.OllamaTimeout})
 	haClient, err := hagateway.New(ctx, cfg.HAGatewayAddr, cfg.TLSDir, cfg.HAGatewayServerName, log)
 	if err != nil {
 		log.Error("ha-gateway client setup failed", "err", err)
@@ -80,7 +80,7 @@ func main() {
 	}()
 
 	lightCache := domain.NewLightCache(cfg.LightCacheTTL, haClient.ListLights)
-	queryApp := app.NewQueryApp(ollamaClient, haClient, lightCache, log)
+	queryApp := app.NewQueryApp(ollamaClient, haClient, lightCache, cfg.OllamaModel, log)
 
 	serverOpts := []grpc.ServerOption{
 		grpc.StatsHandler(otelgrpc.NewServerHandler()),

ai-gateway/internal/adapters/primary/grpc/server.go

@@ -33,7 +33,7 @@ func (s *Server) Query(ctx context.Context, req *aiv1.QueryRequest) (*aiv1.Query
 		ctx = logger.WithLogger(ctx, log)
 	}
 
-	result, err := s.app.Query(ctx, req.GetText())
+	result, err := s.app.Query(ctx, req.GetText(), req.GetModel())
 	if err != nil {
 		return nil, status.Errorf(codes.Unavailable, "query failed: %v", err)
 	}
@@ -41,5 +41,15 @@ func (s *Server) Query(ctx context.Context, req *aiv1.QueryRequest) (*aiv1.Query
 		Reply:       result.Reply,
 		Intent:      result.Intent,
 		ActionTaken: result.ActionTaken,
+		ModelUsed:   result.ModelUsed,
 	}, nil
 }
+
+// ListModels returns the installed model names from Ollama.
+func (s *Server) ListModels(ctx context.Context, _ *aiv1.ListModelsRequest) (*aiv1.ListModelsResponse, error) {
+	names, err := s.app.ListModels(ctx)
+	if err != nil {
+		return nil, status.Errorf(codes.Unavailable, "list models: %v", err)
+	}
+	return &aiv1.ListModelsResponse{Names: names}, nil
+}

ai-gateway/internal/adapters/secondary/ollama/client.go

@@ -6,6 +6,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"net/http"
+	"strings"
 
 	"go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
 )
@@ -14,37 +15,49 @@ type generateRequest struct {
 	Model  string `json:"model"`
 	Prompt string `json:"prompt"`
 	Stream bool   `json:"stream"`
+	Think  *bool  `json:"think,omitempty"`
 }
 
 type generateResponse struct {
 	Response string `json:"response"`
 }
 
+type listModelsResponse struct {
+	Models []struct {
+		Name string `json:"name"`
+	} `json:"models"`
+}
+
 // Client implements the LLM driven port with the Ollama generate API.
 type Client struct {
 	baseURL string
-	model   string
 	http    *http.Client
 }
 
 // New constructs an Ollama client with OTel-instrumented transport.
-func New(baseURL, model string, httpClient *http.Client) *Client {
+func New(baseURL string, httpClient *http.Client) *Client {
 	if httpClient == nil {
 		httpClient = &http.Client{Transport: otelhttp.NewTransport(http.DefaultTransport)}
 	}
 	if httpClient.Transport == nil {
 		httpClient.Transport = otelhttp.NewTransport(http.DefaultTransport)
 	}
-	return &Client{baseURL: baseURL, model: model, http: httpClient}
+	return &Client{baseURL: baseURL, http: httpClient}
 }
 
 // Generate sends one non-streaming prompt to Ollama.
-func (c *Client) Generate(ctx context.Context, prompt string) (string, error) {
+func (c *Client) Generate(ctx context.Context, model, prompt string) (string, error) {
-	body, err := json.Marshal(generateRequest{
+	reqBody := generateRequest{
-		Model:  c.model,
+		Model:  model,
 		Prompt: prompt,
 		Stream: false,
-	})
+	}
+	if isThinkingModel(model) {
+		disabled := false
+		reqBody.Think = &disabled
+	}
+
+	body, err := json.Marshal(reqBody)
 	if err != nil {
 		return "", fmt.Errorf("marshal ollama request: %w", err)
 	}
@@ -71,3 +84,38 @@ func (c *Client) Generate(ctx context.Context, prompt string) (string, error) {
 	}
 	return out.Response, nil
 }
+
+// ListModels returns the installed model names from Ollama.
+func (c *Client) ListModels(ctx context.Context) ([]string, error) {
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, c.baseURL+"/api/tags", nil)
+	if err != nil {
+		return nil, fmt.Errorf("build ollama list models request: %w", err)
+	}
+
+	resp, err := c.http.Do(req)
+	if err != nil {
+		return nil, fmt.Errorf("list ollama models: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
+		return nil, fmt.Errorf("ollama returned status %s", resp.Status)
+	}
+
+	var out listModelsResponse
+	if err := json.NewDecoder(resp.Body).Decode(&out); err != nil {
+		return nil, fmt.Errorf("decode ollama list models response: %w", err)
+	}
+
+	names := make([]string, 0, len(out.Models))
+	for _, model := range out.Models {
+		if model.Name != "" {
+			names = append(names, model.Name)
+		}
+	}
+	return names, nil
+}
+
+func isThinkingModel(name string) bool {
+	return strings.HasPrefix(name, "qwen3")
+}

ai-gateway/internal/adapters/secondary/ollama/client_test.go

@@ -0,0 +1,81 @@
+package ollama
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+func TestIsThinkingModel(t *testing.T) {
+	tests := []struct {
+		name string
+		want bool
+	}{
+		{name: "qwen3", want: true},
+		{name: "qwen3:4b", want: true},
+		{name: "qwen3:latest", want: true},
+		{name: "llama3", want: false},
+		{name: "mistral", want: false},
+	}
+	for _, tt := range tests {
+		if got := isThinkingModel(tt.name); got != tt.want {
+			t.Fatalf("isThinkingModel(%q) = %v, want %v", tt.name, got, tt.want)
+		}
+	}
+}
+
+func TestGenerateSetsThinkForQwen3(t *testing.T) {
+	var body map[string]any
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if err := json.NewDecoder(r.Body).Decode(&body); err != nil {
+			t.Fatalf("Decode() error = %v", err)
+		}
+		_, _ = w.Write([]byte(`{"response":"ok"}`))
+	}))
+	defer srv.Close()
+
+	client := New(srv.URL, srv.Client())
+	if _, err := client.Generate(context.Background(), "qwen3:latest", "prompt"); err != nil {
+		t.Fatalf("Generate() error = %v", err)
+	}
+	if body["think"] != false {
+		t.Fatalf("think = %#v, want false", body["think"])
+	}
+}
+
+func TestGenerateOmitsThinkForLlama3(t *testing.T) {
+	var body map[string]any
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if err := json.NewDecoder(r.Body).Decode(&body); err != nil {
+			t.Fatalf("Decode() error = %v", err)
+		}
+		_, _ = w.Write([]byte(`{"response":"ok"}`))
+	}))
+	defer srv.Close()
+
+	client := New(srv.URL, srv.Client())
+	if _, err := client.Generate(context.Background(), "llama3:latest", "prompt"); err != nil {
+		t.Fatalf("Generate() error = %v", err)
+	}
+	if _, ok := body["think"]; ok {
+		t.Fatalf("unexpected think key = %#v", body["think"])
+	}
+}
+
+func TestListModelsReturnsNamesOnly(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		_, _ = w.Write([]byte(`{"models":[{"name":"llama3:latest"},{"name":"qwen3:latest"}]}`))
+	}))
+	defer srv.Close()
+
+	client := New(srv.URL, srv.Client())
+	got, err := client.ListModels(context.Background())
+	if err != nil {
+		t.Fatalf("ListModels() error = %v", err)
+	}
+	if len(got) != 2 || got[0] != "llama3:latest" || got[1] != "qwen3:latest" {
+		t.Fatalf("ListModels() = %#v", got)
+	}
+}

ai-gateway/internal/app/query.go

@@ -18,6 +18,7 @@ type QueryResult struct {
 	Reply       string
 	Intent      string
 	ActionTaken bool
+	ModelUsed   string
 }
 
 // QueryApp orchestrates one AI query request.
@@ -25,27 +26,32 @@ type QueryApp struct {
 	llm          driven.LLMClient
 	ha           driven.HAClient
 	cache        *domain.LightCache
+	defaultModel string
 	log          *slog.Logger
 }
 
 // NewQueryApp constructs the AI query application service.
-func NewQueryApp(llm driven.LLMClient, ha driven.HAClient, cache *domain.LightCache, log *slog.Logger) *QueryApp {
+func NewQueryApp(llm driven.LLMClient, ha driven.HAClient, cache *domain.LightCache, defaultModel string, log *slog.Logger) *QueryApp {
-	return &QueryApp{llm: llm, ha: ha, cache: cache, log: log}
+	return &QueryApp{llm: llm, ha: ha, cache: cache, defaultModel: defaultModel, log: log}
 }
 
 // Query runs the full intent parsing and dispatch flow for one user request.
-func (a *QueryApp) Query(ctx context.Context, text string) (QueryResult, error) {
+func (a *QueryApp) Query(ctx context.Context, text, model string) (QueryResult, error) {
+	if model == "" {
+		model = a.defaultModel
+	}
 	lights, err := a.cache.Get(ctx)
 	if err != nil {
 		a.log.Error("light cache refresh failed", "err", err)
 		return QueryResult{
 			Reply:       "I couldn't reach Home Assistant right now.",
 			ActionTaken: false,
+			ModelUsed:   model,
 		}, nil
 	}
 
 	prompt := domain.BuildPrompt(text, promptLightLines(lights))
-	raw, err := a.llm.Generate(ctx, prompt)
+	raw, err := a.llm.Generate(ctx, model, prompt)
 	if err != nil {
 		return QueryResult{}, err
 	}
@@ -57,6 +63,7 @@ func (a *QueryApp) Query(ctx context.Context, text string) (QueryResult, error)
 			Reply:       "I didn't understand that.",
 			Intent:      domain.IntentNone,
 			ActionTaken: false,
+			ModelUsed:   model,
 		}, nil
 	}
 
@@ -64,7 +71,7 @@ func (a *QueryApp) Query(ctx context.Context, text string) (QueryResult, error)
 	case domain.IntentTurnOnLight:
 		entityID, ok := resolveLightEntity(intent.Entity, lights)
 		if !ok {
-			return QueryResult{Reply: "I couldn't find that light.", Intent: intent.Name}, nil
+			return QueryResult{Reply: "I couldn't find that light.", Intent: intent.Name, ModelUsed: model}, nil
 		}
 		params, err := ParseLightParams(intent.Params)
 		if err != nil {
@@ -72,6 +79,7 @@ func (a *QueryApp) Query(ctx context.Context, text string) (QueryResult, error)
 				Reply:       "I couldn't understand the light settings.",
 				Intent:      intent.Name,
 				ActionTaken: false,
+				ModelUsed:   model,
 			}, nil
 		}
 		if err := a.ha.TurnOnLight(ctx, entityID, params); err != nil {
@@ -80,17 +88,19 @@ func (a *QueryApp) Query(ctx context.Context, text string) (QueryResult, error)
 				Reply:       "I couldn't reach Home Assistant right now.",
 				Intent:      intent.Name,
 				ActionTaken: false,
+				ModelUsed:   model,
 			}, nil
 		}
 		return QueryResult{
 			Reply:       fallbackReply(intent.Reply, fmt.Sprintf("Turned on `%s`.", displayLightName(entityID, lights))),
 			Intent:      intent.Name,
 			ActionTaken: true,
+			ModelUsed:   model,
 		}, nil
 	case domain.IntentTurnOffLight:
 		entityID, ok := resolveLightEntity(intent.Entity, lights)
 		if !ok {
-			return QueryResult{Reply: "I couldn't find that light.", Intent: intent.Name}, nil
+			return QueryResult{Reply: "I couldn't find that light.", Intent: intent.Name, ModelUsed: model}, nil
 		}
 		if err := a.ha.TurnOffLight(ctx, entityID); err != nil {
 			a.log.Error("turn off light failed", "entity_id", entityID, "err", err)
@@ -98,18 +108,21 @@ func (a *QueryApp) Query(ctx context.Context, text string) (QueryResult, error)
 				Reply:       "I couldn't reach Home Assistant right now.",
 				Intent:      intent.Name,
 				ActionTaken: false,
+				ModelUsed:   model,
 			}, nil
 		}
 		return QueryResult{
 			Reply:       fallbackReply(intent.Reply, fmt.Sprintf("Turned off `%s`.", displayLightName(entityID, lights))),
 			Intent:      intent.Name,
 			ActionTaken: true,
+			ModelUsed:   model,
 		}, nil
 	case domain.IntentListLights:
 		return QueryResult{
 			Reply:       formatLightListReply(lights),
 			Intent:      intent.Name,
 			ActionTaken: false,
+			ModelUsed:   model,
 		}, nil
 	case domain.IntentNone:
 		fallthrough
@@ -118,10 +131,16 @@ func (a *QueryApp) Query(ctx context.Context, text string) (QueryResult, error)
 			Reply:       fallbackReply(intent.Reply, "I didn't understand that."),
 			Intent:      intent.Name,
 			ActionTaken: false,
+			ModelUsed:   model,
 		}, nil
 	}
 }
 
+// ListModels returns the currently installed model names.
+func (a *QueryApp) ListModels(ctx context.Context) ([]string, error) {
+	return a.llm.ListModels(ctx)
+}
+
 func promptLightLines(lights []driven.Light) []string {
 	lines := make([]string, 0, len(lights))
 	for _, light := range lights {

ai-gateway/internal/app/query_test.go

@@ -13,11 +13,19 @@ import (
 )
 
 type fakeLLM struct {
-	generate func(context.Context, string) (string, error)
+	generate   func(context.Context, string, string) (string, error)
+	listModels func(context.Context) ([]string, error)
 }
 
-func (f *fakeLLM) Generate(ctx context.Context, prompt string) (string, error) {
+func (f *fakeLLM) Generate(ctx context.Context, model, prompt string) (string, error) {
-	return f.generate(ctx, prompt)
+	return f.generate(ctx, model, prompt)
+}
+
+func (f *fakeLLM) ListModels(ctx context.Context) ([]string, error) {
+	if f.listModels == nil {
+		return nil, nil
+	}
+	return f.listModels(ctx)
 }
 
 type fakeHA struct {
@@ -54,12 +62,15 @@ func TestQueryAppTurnOnLight(t *testing.T) {
 	ha := &fakeHA{lights: []driven.Light{{EntityID: "light.kitchen", FriendlyName: "Kitchen", State: "off"}}}
 	cache := domain.NewLightCache(time.Hour, ha.ListLights)
 	app := NewQueryApp(&fakeLLM{
-		generate: func(ctx context.Context, prompt string) (string, error) {
+		generate: func(ctx context.Context, model, prompt string) (string, error) {
+			if model != "llama3:latest" {
+				t.Fatalf("Generate() model = %q", model)
+			}
 			return `{"intent":"turn_on_light","entity":"Kitchen","params":{"brightness":"80"},"reply":"Turning on Kitchen."}`, nil
 		},
-	}, ha, cache, slog.Default())
+	}, ha, cache, "llama3:latest", slog.Default())
 
-	got, err := app.Query(context.Background(), "turn on kitchen")
+	got, err := app.Query(context.Background(), "turn on kitchen", "")
 	if err != nil {
 		t.Fatalf("Query() error = %v", err)
 	}
@@ -77,12 +88,12 @@ func TestQueryAppTurnOnLight(t *testing.T) {
 func TestQueryAppInvalidJSON(t *testing.T) {
 	ha := &fakeHA{lights: []driven.Light{{EntityID: "light.kitchen", FriendlyName: "Kitchen", State: "off"}}}
 	app := NewQueryApp(&fakeLLM{
-		generate: func(ctx context.Context, prompt string) (string, error) {
+		generate: func(ctx context.Context, model, prompt string) (string, error) {
 			return `not-json`, nil
 		},
-	}, ha, domain.NewLightCache(time.Hour, ha.ListLights), slog.Default())
+	}, ha, domain.NewLightCache(time.Hour, ha.ListLights), "llama3:latest", slog.Default())
 
-	got, err := app.Query(context.Background(), "turn on kitchen")
+	got, err := app.Query(context.Background(), "turn on kitchen", "")
 	if err != nil {
 		t.Fatalf("Query() error = %v", err)
 	}
@@ -97,12 +108,12 @@ func TestQueryAppInvalidJSON(t *testing.T) {
 func TestQueryAppIntentNone(t *testing.T) {
 	ha := &fakeHA{lights: []driven.Light{{EntityID: "light.kitchen", FriendlyName: "Kitchen", State: "off"}}}
 	app := NewQueryApp(&fakeLLM{
-		generate: func(ctx context.Context, prompt string) (string, error) {
+		generate: func(ctx context.Context, model, prompt string) (string, error) {
 			return `{"intent":"none","entity":"","params":{},"reply":"Hello there."}`, nil
 		},
-	}, ha, domain.NewLightCache(time.Hour, ha.ListLights), slog.Default())
+	}, ha, domain.NewLightCache(time.Hour, ha.ListLights), "llama3:latest", slog.Default())
 
-	got, err := app.Query(context.Background(), "hello")
+	got, err := app.Query(context.Background(), "hello", "")
 	if err != nil {
 		t.Fatalf("Query() error = %v", err)
 	}
@@ -117,12 +128,12 @@ func TestQueryAppHAFailure(t *testing.T) {
 		turnOnErr: errors.New("boom"),
 	}
 	app := NewQueryApp(&fakeLLM{
-		generate: func(ctx context.Context, prompt string) (string, error) {
+		generate: func(ctx context.Context, model, prompt string) (string, error) {
 			return `{"intent":"turn_on_light","entity":"light.kitchen","params":{},"reply":"Turning on Kitchen."}`, nil
 		},
-	}, ha, domain.NewLightCache(time.Hour, ha.ListLights), slog.Default())
+	}, ha, domain.NewLightCache(time.Hour, ha.ListLights), "llama3:latest", slog.Default())
 
-	got, err := app.Query(context.Background(), "turn on kitchen")
+	got, err := app.Query(context.Background(), "turn on kitchen", "")
 	if err != nil {
 		t.Fatalf("Query() error = %v", err)
 	}
@@ -134,12 +145,12 @@ func TestQueryAppHAFailure(t *testing.T) {
 func TestQueryAppListLights(t *testing.T) {
 	ha := &fakeHA{lights: []driven.Light{{EntityID: "light.kitchen", FriendlyName: "Kitchen", State: "on"}}}
 	app := NewQueryApp(&fakeLLM{
-		generate: func(ctx context.Context, prompt string) (string, error) {
+		generate: func(ctx context.Context, model, prompt string) (string, error) {
 			return `{"intent":"list_lights","entity":"","params":{},"reply":""}`, nil
 		},
-	}, ha, domain.NewLightCache(time.Hour, ha.ListLights), slog.Default())
+	}, ha, domain.NewLightCache(time.Hour, ha.ListLights), "llama3:latest", slog.Default())
 
-	got, err := app.Query(context.Background(), "what lights exist")
+	got, err := app.Query(context.Background(), "what lights exist", "")
 	if err != nil {
 		t.Fatalf("Query() error = %v", err)
 	}
@@ -164,3 +175,42 @@ func TestLightCacheRefreshAfterTTL(t *testing.T) {
 		t.Fatalf("ListLights calls = %d, want at least 2", ha.listCalls)
 	}
 }
+
+func TestQueryAppExplicitModel(t *testing.T) {
+	ha := &fakeHA{lights: []driven.Light{{EntityID: "light.kitchen", FriendlyName: "Kitchen", State: "off"}}}
+	app := NewQueryApp(&fakeLLM{
+		generate: func(ctx context.Context, model, prompt string) (string, error) {
+			if model != "qwen3:latest" {
+				t.Fatalf("Generate() model = %q", model)
+			}
+			return `{"intent":"none","entity":"","params":{},"reply":"Hello there."}`, nil
+		},
+	}, ha, domain.NewLightCache(time.Hour, ha.ListLights), "llama3:latest", slog.Default())
+
+	got, err := app.Query(context.Background(), "hello", "qwen3:latest")
+	if err != nil {
+		t.Fatalf("Query() error = %v", err)
+	}
+	if got.ModelUsed != "qwen3:latest" {
+		t.Fatalf("ModelUsed = %q", got.ModelUsed)
+	}
+}
+
+func TestQueryAppListModels(t *testing.T) {
+	app := NewQueryApp(&fakeLLM{
+		generate: func(ctx context.Context, model, prompt string) (string, error) {
+			return "", nil
+		},
+		listModels: func(ctx context.Context) ([]string, error) {
+			return []string{"llama3:latest", "qwen3:latest"}, nil
+		},
+	}, &fakeHA{}, domain.NewLightCache(time.Hour, func(context.Context) ([]driven.Light, error) { return nil, nil }), "llama3:latest", slog.Default())
+
+	got, err := app.ListModels(context.Background())
+	if err != nil {
+		t.Fatalf("ListModels() error = %v", err)
+	}
+	if !reflect.DeepEqual(got, []string{"llama3:latest", "qwen3:latest"}) {
+		t.Fatalf("ListModels() = %#v", got)
+	}
+}

ai-gateway/internal/core/ports/driven/llm.go

@@ -4,5 +4,6 @@ import "context"
 
 // LLMClient generates one model response for a prompt.
 type LLMClient interface {
-	Generate(ctx context.Context, prompt string) (string, error)
+	Generate(ctx context.Context, model, prompt string) (string, error)
+	ListModels(ctx context.Context) ([]string, error)
 }

discord-bot/cmd/bot/main.go

@@ -17,6 +17,8 @@ import (
 	"gitea.nik4nao.com/nik/home-services/discord-bot/internal/app"
 	"gitea.nik4nao.com/nik/home-services/discord-bot/internal/config"
 	"gitea.nik4nao.com/nik/home-services/discord-bot/internal/logger"
+	"gitea.nik4nao.com/nik/home-services/discord-bot/internal/modelstore"
+	"gitea.nik4nao.com/nik/home-services/discord-bot/internal/modelvalidator"
 	"gitea.nik4nao.com/nik/home-services/discord-bot/internal/telemetry"
 )
 
@@ -84,7 +86,9 @@ func main() {
 		}
 	}()
 
-	commandApp := app.NewCommandApp(haClient, aiClient)
+	modelStore := modelstore.New()
+	validator := modelvalidator.New(aiClient, 30*time.Second)
+	commandApp := app.NewCommandApp(haClient, aiClient, modelStore, validator)
 
 	// Discord-specific wiring stays at the edge so the app layer remains transport-agnostic.
 	session, err := discordgo.New("Bot " + cfg.DiscordToken)

discord-bot/internal/adapters/primary/discord/handler.go

@@ -24,8 +24,12 @@ type commandHandler interface {
 	HandleLightToggle(ctx context.Context, entityID string) (string, error)
 	HandleSwitchList(ctx context.Context) (string, error)
 	HandleAIQuery(ctx context.Context, text string) (string, error)
+	HandleAIModelSet(ctx context.Context, name string) (string, error)
+	HandleAIModelGet(ctx context.Context) (string, error)
+	HandleAIModelList(ctx context.Context) (string, error)
 	AutocompleteLights(ctx context.Context) ([]apppkg.Choice, error)
 	AutocompleteSwitches(ctx context.Context) ([]apppkg.Choice, error)
+	AutocompleteAIModels(ctx context.Context) ([]apppkg.Choice, error)
 }
 
 // Handler adapts Discord interactions to the command application layer.
@@ -69,6 +73,9 @@ func (h *Handler) handleApplicationCommand(ctx context.Context, s *discordgo.Ses
 	command := data.Name
 	if len(data.Options) > 0 {
 		command += "." + data.Options[0].Name
+		if len(data.Options[0].Options) > 0 && data.Options[0].Type == discordgo.ApplicationCommandOptionSubCommandGroup {
+			command += "." + data.Options[0].Options[0].Name
+		}
 	}
 	user := ""
 	if i.Member != nil && i.Member.User != nil {
@@ -90,7 +97,18 @@ func (h *Handler) handleApplicationCommand(ctx context.Context, s *discordgo.Ses
 	}
 
 	sub := data.Options[0]
-	switch data.Name + "." + sub.Name {
+	commandPath := data.Name + "." + sub.Name
+	target := sub
+	if sub.Type == discordgo.ApplicationCommandOptionSubCommandGroup {
+		if len(sub.Options) == 0 {
+			h.respondError(ctx, s, i.Interaction, true, start, fmt.Errorf("missing grouped subcommand"))
+			return
+		}
+		target = sub.Options[0]
+		commandPath += "." + target.Name
+	}
+
+	switch commandPath {
 	case "light.list":
 		msg, err := h.app.HandleLightList(ctx)
 		if err != nil {
@@ -145,10 +163,38 @@ func (h *Handler) handleApplicationCommand(ctx context.Context, s *discordgo.Ses
 			)
 			return
 		}
-		msg, err := h.app.HandleAIQuery(ctx, requiredStringOption(sub, "text"))
+		msg, err := h.app.HandleAIQuery(ctx, requiredStringOption(target, "text"))
+		h.followup(ctx, s, i.Interaction, msg, true, start, err)
+	case "ai.model.set":
+		if err := h.deferResponse(s, i.Interaction, true); err != nil {
+			log.Error("discord response failed",
+				"duration_ms", time.Since(start).Milliseconds(),
+				"error", err.Error(),
+			)
+			return
+		}
+		msg, err := h.app.HandleAIModelSet(ctx, requiredStringOption(target, "name"))
+		h.followup(ctx, s, i.Interaction, msg, true, start, err)
+	case "ai.model.get":
+		msg, err := h.app.HandleAIModelGet(ctx)
+		if err != nil {
+			h.respondError(ctx, s, i.Interaction, true, start, err)
+			return
+		}
+		h.respondMessage(ctx, s, i.Interaction, msg, true)
+		log.Info("command handled", "duration_ms", time.Since(start).Milliseconds())
+	case "ai.model.list":
+		if err := h.deferResponse(s, i.Interaction, true); err != nil {
+			log.Error("discord response failed",
+				"duration_ms", time.Since(start).Milliseconds(),
+				"error", err.Error(),
+			)
+			return
+		}
+		msg, err := h.app.HandleAIModelList(ctx)
 		h.followup(ctx, s, i.Interaction, msg, true, start, err)
 	default:
-		h.respondError(ctx, s, i.Interaction, true, start, fmt.Errorf("unsupported command: %s.%s", data.Name, sub.Name))
+		h.respondError(ctx, s, i.Interaction, true, start, fmt.Errorf("unsupported command: %s", commandPath))
 	}
 }
 
@@ -167,6 +213,10 @@ func (h *Handler) handleAutocomplete(ctx context.Context, s *discordgo.Session,
 		choices, err = h.app.AutocompleteLights(ctx)
 	case "switch":
 		choices, err = h.app.AutocompleteSwitches(ctx)
+	case "ai":
+		if focusedOptionName(data) == "name" {
+			choices, err = h.app.AutocompleteAIModels(ctx)
+		}
 	default:
 		choices = nil
 	}
@@ -299,6 +349,15 @@ func optionalUint32Option(sub *discordgo.ApplicationCommandInteractionDataOption
 
 func focusedOptionValue(data discordgo.ApplicationCommandInteractionData) string {
 	for _, sub := range data.Options {
+		if sub.Type == discordgo.ApplicationCommandOptionSubCommandGroup {
+			for _, nested := range sub.Options {
+				for _, opt := range nested.Options {
+					if opt.Focused {
+						return opt.StringValue()
+					}
+				}
+			}
+		}
 		for _, opt := range sub.Options {
 			if opt.Focused {
 				return opt.StringValue()
@@ -307,3 +366,23 @@ func focusedOptionValue(data discordgo.ApplicationCommandInteractionData) string
 	}
 	return ""
 }
+
+func focusedOptionName(data discordgo.ApplicationCommandInteractionData) string {
+	for _, sub := range data.Options {
+		if sub.Type == discordgo.ApplicationCommandOptionSubCommandGroup {
+			for _, nested := range sub.Options {
+				for _, opt := range nested.Options {
+					if opt.Focused {
+						return opt.Name
+					}
+				}
+			}
+		}
+		for _, opt := range sub.Options {
+			if opt.Focused {
+				return opt.Name
+			}
+		}
+	}
+	return ""
+}

discord-bot/internal/adapters/primary/discord/register.go

@@ -98,6 +98,37 @@ func RegisterCommands(s *discordgo.Session, guildID string) error {
 						},
 					},
 				},
+				{
+					Type:        discordgo.ApplicationCommandOptionSubCommandGroup,
+					Name:        "model",
+					Description: "Manage the active AI model",
+					Options: []*discordgo.ApplicationCommandOption{
+						{
+							Type:        discordgo.ApplicationCommandOptionSubCommand,
+							Name:        "set",
+							Description: "Set the active model",
+							Options: []*discordgo.ApplicationCommandOption{
+								{
+									Type:         discordgo.ApplicationCommandOptionString,
+									Name:         "name",
+									Description:  "Model name",
+									Required:     true,
+									Autocomplete: true,
+								},
+							},
+						},
+						{
+							Type:        discordgo.ApplicationCommandOptionSubCommand,
+							Name:        "get",
+							Description: "Show the active model",
+						},
+						{
+							Type:        discordgo.ApplicationCommandOptionSubCommand,
+							Name:        "list",
+							Description: "List available models",
+						},
+					},
+				},
 			},
 		},
 	}

discord-bot/internal/adapters/secondary/aigateway/client.go

@@ -61,22 +61,39 @@ func (c *Client) Close() error {
 }
 
 // Query forwards one free-form request to ai-gateway.
-func (c *Client) Query(ctx context.Context, text string) (string, error) {
+func (c *Client) Query(ctx context.Context, text, model string) (string, string, error) {
 	start := time.Now()
 	log := logger.FromContext(ctx).With("grpc.method", "AIService/Query")
 	resp, err := c.client.Query(ctx, &aiv1.QueryRequest{
 		Text:   text,
 		Source: "discord-bot",
+		Model:  model,
 	})
 	if err != nil {
 		log.Error("grpc call failed",
 			"duration_ms", time.Since(start).Milliseconds(),
 			"error", err.Error(),
 		)
-		return "", fmt.Errorf("query ai-gateway: %w", err)
+		return "", "", fmt.Errorf("query ai-gateway: %w", err)
 	}
 	log.Debug("grpc call completed", "duration_ms", time.Since(start).Milliseconds())
-	return resp.GetReply(), nil
+	return resp.GetReply(), resp.GetModelUsed(), nil
+}
+
+// ListModels returns the installed model names from ai-gateway.
+func (c *Client) ListModels(ctx context.Context) ([]string, error) {
+	start := time.Now()
+	log := logger.FromContext(ctx).With("grpc.method", "AIService/ListModels")
+	resp, err := c.client.ListModels(ctx, &aiv1.ListModelsRequest{})
+	if err != nil {
+		log.Error("grpc call failed",
+			"duration_ms", time.Since(start).Milliseconds(),
+			"error", err.Error(),
+		)
+		return nil, fmt.Errorf("list ai-gateway models: %w", err)
+	}
+	log.Debug("grpc call completed", "duration_ms", time.Since(start).Milliseconds())
+	return append([]string(nil), resp.GetNames()...), nil
 }
 
 func loadTransportCredentials(tlsDir string) (credentials.TransportCredentials, error) {

discord-bot/internal/app/command.go

@@ -7,6 +7,8 @@ import (
 	"strings"
 
 	"gitea.nik4nao.com/nik/home-services/discord-bot/internal/core/ports/driven"
+	"gitea.nik4nao.com/nik/home-services/discord-bot/internal/modelstore"
+	"gitea.nik4nao.com/nik/home-services/discord-bot/internal/modelvalidator"
 )
 
 // Choice is one Discord autocomplete entry.
@@ -19,11 +21,13 @@ type Choice struct {
 type CommandApp struct {
 	ha        driven.HAGateway
 	ai        driven.AIGateway
+	models    *modelstore.Store
+	validator *modelvalidator.Validator
 }
 
 // NewCommandApp constructs the Discord command application service.
-func NewCommandApp(ha driven.HAGateway, ai driven.AIGateway) *CommandApp {
+func NewCommandApp(ha driven.HAGateway, ai driven.AIGateway, models *modelstore.Store, validator *modelvalidator.Validator) *CommandApp {
-	return &CommandApp{ha: ha, ai: ai}
+	return &CommandApp{ha: ha, ai: ai, models: models, validator: validator}
 }
 
 // HandleLightList formats discovered lights into a monospace-friendly response.
@@ -124,11 +128,72 @@ func (a *CommandApp) HandleSwitchList(ctx context.Context) (string, error) {
 
 // HandleAIQuery forwards a free-form request to ai-gateway.
 func (a *CommandApp) HandleAIQuery(ctx context.Context, text string) (string, error) {
-	reply, err := a.ai.Query(ctx, text)
+	reply, modelUsed, err := a.ai.Query(ctx, text, a.models.Get())
 	if err != nil {
 		return "", fmt.Errorf("handle ai query: %w", err)
 	}
-	return reply, nil
+	return fmt.Sprintf("%s\n\n_(via %s)_", reply, modelUsed), nil
+}
+
+// HandleAIModelSet validates and stores the selected model globally.
+func (a *CommandApp) HandleAIModelSet(ctx context.Context, name string) (string, error) {
+	canonical, err := a.validator.Normalize(ctx, name)
+	if err != nil {
+		if err.Error() == "ambiguous model name" {
+			return "", fmt.Errorf("unknown model: %s. Be more specific.", name)
+		}
+		if err.Error() == "unknown model" {
+			return "", fmt.Errorf("unknown model: %s. Try /ai model list.", name)
+		}
+		return "", fmt.Errorf("validate model: %w", err)
+	}
+	a.models.Set(canonical)
+	return fmt.Sprintf("Active model set to `%s`.", canonical), nil
+}
+
+// HandleAIModelGet reports the current selected model or default state.
+func (a *CommandApp) HandleAIModelGet(ctx context.Context) (string, error) {
+	cur := a.models.Get()
+	if cur == "" {
+		return "No model override set. Using ai-gateway default.", nil
+	}
+	return fmt.Sprintf("Active model: `%s`", cur), nil
+}
+
+// HandleAIModelList shows the installed models and marks the active selection.
+func (a *CommandApp) HandleAIModelList(ctx context.Context) (string, error) {
+	models, err := a.validator.Known(ctx)
+	if err != nil {
+		return "", fmt.Errorf("list models: %w", err)
+	}
+	if len(models) == 0 {
+		return "No models installed on the Ollama host.", nil
+	}
+
+	active := a.models.Get()
+	lines := make([]string, 0, len(models)+1)
+	lines = append(lines, "Available models:")
+	for _, model := range models {
+		marker := ""
+		if model == active {
+			marker = " <- active"
+		}
+		lines = append(lines, fmt.Sprintf("- `%s`%s", model, marker))
+	}
+	return strings.Join(lines, "\n"), nil
+}
+
+// AutocompleteAIModels returns model names for the /ai model set command.
+func (a *CommandApp) AutocompleteAIModels(ctx context.Context) ([]Choice, error) {
+	models, err := a.validator.Known(ctx)
+	if err != nil {
+		return nil, fmt.Errorf("autocomplete ai models: %w", err)
+	}
+	choices := make([]Choice, 0, len(models))
+	for _, model := range models {
+		choices = append(choices, Choice{Label: model, Value: model})
+	}
+	return choices, nil
 }
 
 // AutocompleteLights maps discovered lights into Discord autocomplete choices.

discord-bot/internal/app/command_test.go

@@ -5,8 +5,11 @@ import (
 	"errors"
 	"reflect"
 	"testing"
+	"time"
 
 	"gitea.nik4nao.com/nik/home-services/discord-bot/internal/core/ports/driven"
+	"gitea.nik4nao.com/nik/home-services/discord-bot/internal/modelstore"
+	"gitea.nik4nao.com/nik/home-services/discord-bot/internal/modelvalidator"
 )
 
 type mockHAGateway struct {
@@ -18,7 +21,8 @@ type mockHAGateway struct {
 }
 
 type mockAIGateway struct {
-	queryFunc func(ctx context.Context, text string) (string, error)
+	queryFunc      func(ctx context.Context, text, model string) (string, string, error)
+	listModelsFunc func(ctx context.Context) ([]string, error)
 }
 
 func (m *mockHAGateway) ListLights(ctx context.Context) ([]driven.Light, error) {
@@ -56,11 +60,22 @@ func (m *mockHAGateway) ToggleLight(ctx context.Context, entityID string) error
 	return m.toggleLightFunc(ctx, entityID)
 }
 
-func (m *mockAIGateway) Query(ctx context.Context, text string) (string, error) {
+func (m *mockAIGateway) Query(ctx context.Context, text, model string) (string, string, error) {
 	if m.queryFunc == nil {
-		return "", nil
+		return "", "", nil
 	}
-	return m.queryFunc(ctx, text)
+	return m.queryFunc(ctx, text, model)
+}
+
+func (m *mockAIGateway) ListModels(ctx context.Context) ([]string, error) {
+	if m.listModelsFunc == nil {
+		return nil, nil
+	}
+	return m.listModelsFunc(ctx)
+}
+
+func newTestCommandApp(ha *mockHAGateway, ai *mockAIGateway) *CommandApp {
+	return NewCommandApp(ha, ai, modelstore.New(), modelvalidator.New(ai, time.Minute))
 }
 
 func TestCommandAppHandleLightList(t *testing.T) {
@@ -102,7 +117,7 @@ func TestCommandAppHandleLightList(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			app := NewCommandApp(&mockHAGateway{
+			app := newTestCommandApp(&mockHAGateway{
 				listLightsFunc: func(ctx context.Context) ([]driven.Light, error) {
 					return tt.lights, nil
 				},
@@ -183,7 +198,7 @@ func TestCommandAppHandleLightOn(t *testing.T) {
 			var gotBrightness *uint32
 			var gotColorTemp *uint32
 
-			app := NewCommandApp(&mockHAGateway{
+			app := newTestCommandApp(&mockHAGateway{
 				listLightsFunc: func(ctx context.Context) ([]driven.Light, error) {
 					if tt.listErr != nil {
 						return nil, tt.listErr
@@ -258,7 +273,7 @@ func TestCommandAppHandleLightOff(t *testing.T) {
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
 			var gotTransition *uint32
-			app := NewCommandApp(&mockHAGateway{
+			app := newTestCommandApp(&mockHAGateway{
 				listLightsFunc: func(ctx context.Context) ([]driven.Light, error) {
 					return tt.lights, nil
 				},
@@ -317,7 +332,7 @@ func TestCommandAppHandleLightToggle(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			app := NewCommandApp(&mockHAGateway{
+			app := newTestCommandApp(&mockHAGateway{
 				listLightsFunc: func(ctx context.Context) ([]driven.Light, error) {
 					if tt.listErr != nil {
 						return nil, tt.listErr
@@ -368,7 +383,7 @@ func TestCommandAppHandleSwitchList(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			app := NewCommandApp(&mockHAGateway{
+			app := newTestCommandApp(&mockHAGateway{
 				listSwitchesFunc: func(ctx context.Context) ([]driven.Switch, error) {
 					return tt.switches, nil
 				},
@@ -413,7 +428,7 @@ func TestCommandAppAutocompleteLights(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			app := NewCommandApp(&mockHAGateway{
+			app := newTestCommandApp(&mockHAGateway{
 				listLightsFunc: func(ctx context.Context) ([]driven.Light, error) {
 					if tt.listErr != nil {
 						return nil, tt.listErr
@@ -467,7 +482,7 @@ func TestCommandAppAutocompleteSwitches(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			app := NewCommandApp(&mockHAGateway{
+			app := newTestCommandApp(&mockHAGateway{
 				listSwitchesFunc: func(ctx context.Context) ([]driven.Switch, error) {
 					if tt.listErr != nil {
 						return nil, tt.listErr
@@ -494,20 +509,41 @@ func TestCommandAppAutocompleteSwitches(t *testing.T) {
 }
 
 func TestCommandAppHandleAIQuery(t *testing.T) {
+	store := modelstore.New()
+	store.Set("llama3:latest")
 	app := NewCommandApp(&mockHAGateway{}, &mockAIGateway{
-		queryFunc: func(ctx context.Context, text string) (string, error) {
+		queryFunc: func(ctx context.Context, text, model string) (string, string, error) {
 			if text != "turn on kitchen" {
 				t.Fatalf("Query() text = %q", text)
 			}
-			return "Turning on Kitchen.", nil
+			if model != "llama3:latest" {
+				t.Fatalf("Query() model = %q", model)
+			}
+			return "Turning on Kitchen.", "llama3:latest", nil
 		},
-	})
+	}, store, modelvalidator.New(&mockAIGateway{}, time.Minute))
 
 	got, err := app.HandleAIQuery(context.Background(), "turn on kitchen")
 	if err != nil {
 		t.Fatalf("HandleAIQuery() error = %v", err)
 	}
-	if got != "Turning on Kitchen." {
+	if got != "Turning on Kitchen.\n\n_(via llama3:latest)_" {
 		t.Fatalf("HandleAIQuery() = %q", got)
 	}
 }
+
+func TestCommandAppHandleAIModelSet(t *testing.T) {
+	app := newTestCommandApp(&mockHAGateway{}, &mockAIGateway{
+		listModelsFunc: func(ctx context.Context) ([]string, error) {
+			return []string{"llama3:latest"}, nil
+		},
+	})
+
+	got, err := app.HandleAIModelSet(context.Background(), "llama3")
+	if err != nil {
+		t.Fatalf("HandleAIModelSet() error = %v", err)
+	}
+	if got != "Active model set to `llama3:latest`." {
+		t.Fatalf("HandleAIModelSet() = %q", got)
+	}
+}

discord-bot/internal/core/ports/driven/ai.go

@@ -4,5 +4,6 @@ import "context"
 
 // AIGateway exposes the free-form AI query API used by the Discord bot.
 type AIGateway interface {
-	Query(ctx context.Context, text string) (string, error)
+	Query(ctx context.Context, text, model string) (reply, modelUsed string, err error)
+	ListModels(ctx context.Context) ([]string, error)
 }

discord-bot/internal/modelstore/store.go

@@ -0,0 +1,28 @@
+package modelstore
+
+import "sync"
+
+// Store keeps the globally selected AI model in memory.
+type Store struct {
+	mu       sync.RWMutex
+	selected string
+}
+
+// New constructs an empty in-memory model store.
+func New() *Store {
+	return &Store{}
+}
+
+// Get returns the currently selected model, or empty for default behavior.
+func (s *Store) Get() string {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return s.selected
+}
+
+// Set updates the currently selected model.
+func (s *Store) Set(model string) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	s.selected = model
+}

discord-bot/internal/modelstore/store_test.go

@@ -0,0 +1,15 @@
+package modelstore
+
+import "testing"
+
+func TestStoreGetSet(t *testing.T) {
+	store := New()
+	if got := store.Get(); got != "" {
+		t.Fatalf("Get() = %q, want empty", got)
+	}
+
+	store.Set("llama3:latest")
+	if got := store.Get(); got != "llama3:latest" {
+		t.Fatalf("Get() = %q, want llama3:latest", got)
+	}
+}

discord-bot/internal/modelvalidator/validator.go

@@ -0,0 +1,86 @@
+package modelvalidator
+
+import (
+	"context"
+	"fmt"
+	"strings"
+	"sync"
+	"time"
+
+	"gitea.nik4nao.com/nik/home-services/discord-bot/internal/core/ports/driven"
+)
+
+// Validator caches the model list briefly and normalizes friendly names.
+type Validator struct {
+	client driven.AIGateway
+	ttl    time.Duration
+
+	mu       sync.Mutex
+	cache    []string
+	cachedAt time.Time
+}
+
+// New constructs a model validator with a TTL cache.
+func New(client driven.AIGateway, ttl time.Duration) *Validator {
+	return &Validator{client: client, ttl: ttl}
+}
+
+// Known returns the cached model list, refreshing when stale.
+func (v *Validator) Known(ctx context.Context) ([]string, error) {
+	v.mu.Lock()
+	defer v.mu.Unlock()
+	if len(v.cache) > 0 && time.Since(v.cachedAt) < v.ttl {
+		return append([]string(nil), v.cache...), nil
+	}
+	models, err := v.client.ListModels(ctx)
+	if err != nil {
+		return nil, err
+	}
+	v.cache = append([]string(nil), models...)
+	v.cachedAt = time.Now()
+	return append([]string(nil), v.cache...), nil
+}
+
+// Normalize resolves a user-provided name to a canonical installed model name.
+func (v *Validator) Normalize(ctx context.Context, name string) (string, error) {
+	models, err := v.Known(ctx)
+	if err != nil {
+		return "", err
+	}
+	for _, model := range models {
+		if model == name {
+			return model, nil
+		}
+	}
+	latest := name + ":latest"
+	for _, model := range models {
+		if model == latest {
+			return model, nil
+		}
+	}
+
+	lower := strings.ToLower(name)
+	for _, model := range models {
+		if strings.ToLower(model) == lower {
+			return model, nil
+		}
+	}
+	lowerLatest := strings.ToLower(latest)
+	for _, model := range models {
+		if strings.ToLower(model) == lowerLatest {
+			return model, nil
+		}
+	}
+
+	matches := make([]string, 0, 2)
+	prefix := lower + ":"
+	for _, model := range models {
+		if strings.HasPrefix(strings.ToLower(model), prefix) {
+			matches = append(matches, model)
+		}
+	}
+	if len(matches) > 1 {
+		return "", fmt.Errorf("ambiguous model name")
+	}
+	return "", fmt.Errorf("unknown model")
+}

discord-bot/internal/modelvalidator/validator_test.go

@@ -0,0 +1,70 @@
+package modelvalidator
+
+import (
+	"context"
+	"errors"
+	"testing"
+	"time"
+)
+
+type fakeAIGateway struct {
+	listModels func(context.Context) ([]string, error)
+}
+
+func (f *fakeAIGateway) Query(ctx context.Context, text, model string) (string, string, error) {
+	return "", "", nil
+}
+
+func (f *fakeAIGateway) ListModels(ctx context.Context) ([]string, error) {
+	return f.listModels(ctx)
+}
+
+func TestValidatorNormalize(t *testing.T) {
+	v := New(&fakeAIGateway{
+		listModels: func(ctx context.Context) ([]string, error) {
+			return []string{"llama3:latest", "qwen3:latest", "qwen3:4b"}, nil
+		},
+	}, time.Minute)
+
+	got, err := v.Normalize(context.Background(), "llama3")
+	if err != nil || got != "llama3:latest" {
+		t.Fatalf("Normalize(llama3) = %q, %v", got, err)
+	}
+
+	got, err = v.Normalize(context.Background(), "qwen3")
+	if err != nil || got != "qwen3:latest" {
+		t.Fatalf("Normalize(qwen3) = %q, %v", got, err)
+	}
+}
+
+func TestValidatorKnownCaches(t *testing.T) {
+	calls := 0
+	v := New(&fakeAIGateway{
+		listModels: func(ctx context.Context) ([]string, error) {
+			calls++
+			return []string{"llama3:latest"}, nil
+		},
+	}, time.Minute)
+
+	if _, err := v.Known(context.Background()); err != nil {
+		t.Fatalf("Known() error = %v", err)
+	}
+	if _, err := v.Known(context.Background()); err != nil {
+		t.Fatalf("Known() error = %v", err)
+	}
+	if calls != 1 {
+		t.Fatalf("calls = %d, want 1", calls)
+	}
+}
+
+func TestValidatorKnownPropagatesError(t *testing.T) {
+	v := New(&fakeAIGateway{
+		listModels: func(ctx context.Context) ([]string, error) {
+			return nil, errors.New("boom")
+		},
+	}, time.Minute)
+
+	if _, err := v.Known(context.Background()); err == nil {
+		t.Fatal("Known() error = nil, want error")
+	}
+}

gen/ai/v1/ai.pb.go

@@ -25,6 +25,7 @@ type QueryRequest struct {
 	state         protoimpl.MessageState `protogen:"open.v1"`
 	Text          string                 `protobuf:"bytes,1,opt,name=text,proto3" json:"text,omitempty"`
 	Source        string                 `protobuf:"bytes,2,opt,name=source,proto3" json:"source,omitempty"`
+	Model         string                 `protobuf:"bytes,3,opt,name=model,proto3" json:"model,omitempty"`
 	unknownFields protoimpl.UnknownFields
 	sizeCache     protoimpl.SizeCache
 }
@@ -73,11 +74,19 @@ func (x *QueryRequest) GetSource() string {
 	return ""
 }
 
+func (x *QueryRequest) GetModel() string {
+	if x != nil {
+		return x.Model
+	}
+	return ""
+}
+
 type QueryResponse struct {
 	state         protoimpl.MessageState `protogen:"open.v1"`
 	Reply         string                 `protobuf:"bytes,1,opt,name=reply,proto3" json:"reply,omitempty"`
 	Intent        string                 `protobuf:"bytes,2,opt,name=intent,proto3" json:"intent,omitempty"`
 	ActionTaken   bool                   `protobuf:"varint,3,opt,name=action_taken,json=actionTaken,proto3" json:"action_taken,omitempty"`
+	ModelUsed     string                 `protobuf:"bytes,4,opt,name=model_used,json=modelUsed,proto3" json:"model_used,omitempty"`
 	unknownFields protoimpl.UnknownFields
 	sizeCache     protoimpl.SizeCache
 }
@@ -133,20 +142,115 @@ func (x *QueryResponse) GetActionTaken() bool {
 	return false
 }
 
+func (x *QueryResponse) GetModelUsed() string {
+	if x != nil {
+		return x.ModelUsed
+	}
+	return ""
+}
+
+type ListModelsRequest struct {
+	state         protoimpl.MessageState `protogen:"open.v1"`
+	unknownFields protoimpl.UnknownFields
+	sizeCache     protoimpl.SizeCache
+}
+
+func (x *ListModelsRequest) Reset() {
+	*x = ListModelsRequest{}
+	mi := &file_ai_v1_ai_proto_msgTypes[2]
+	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+	ms.StoreMessageInfo(mi)
+}
+
+func (x *ListModelsRequest) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*ListModelsRequest) ProtoMessage() {}
+
+func (x *ListModelsRequest) ProtoReflect() protoreflect.Message {
+	mi := &file_ai_v1_ai_proto_msgTypes[2]
+	if x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use ListModelsRequest.ProtoReflect.Descriptor instead.
+func (*ListModelsRequest) Descriptor() ([]byte, []int) {
+	return file_ai_v1_ai_proto_rawDescGZIP(), []int{2}
+}
+
+type ListModelsResponse struct {
+	state         protoimpl.MessageState `protogen:"open.v1"`
+	Names         []string               `protobuf:"bytes,1,rep,name=names,proto3" json:"names,omitempty"`
+	unknownFields protoimpl.UnknownFields
+	sizeCache     protoimpl.SizeCache
+}
+
+func (x *ListModelsResponse) Reset() {
+	*x = ListModelsResponse{}
+	mi := &file_ai_v1_ai_proto_msgTypes[3]
+	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+	ms.StoreMessageInfo(mi)
+}
+
+func (x *ListModelsResponse) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*ListModelsResponse) ProtoMessage() {}
+
+func (x *ListModelsResponse) ProtoReflect() protoreflect.Message {
+	mi := &file_ai_v1_ai_proto_msgTypes[3]
+	if x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use ListModelsResponse.ProtoReflect.Descriptor instead.
+func (*ListModelsResponse) Descriptor() ([]byte, []int) {
+	return file_ai_v1_ai_proto_rawDescGZIP(), []int{3}
+}
+
+func (x *ListModelsResponse) GetNames() []string {
+	if x != nil {
+		return x.Names
+	}
+	return nil
+}
+
 var File_ai_v1_ai_proto protoreflect.FileDescriptor
 
 const file_ai_v1_ai_proto_rawDesc = "" +
 	"\n" +
-	"\x0eai/v1/ai.proto\x12\x05ai.v1\":\n" +
+	"\x0eai/v1/ai.proto\x12\x05ai.v1\"P\n" +
 	"\fQueryRequest\x12\x12\n" +
 	"\x04text\x18\x01 \x01(\tR\x04text\x12\x16\n" +
-	"\x06source\x18\x02 \x01(\tR\x06source\"`\n" +
+	"\x06source\x18\x02 \x01(\tR\x06source\x12\x14\n" +
+	"\x05model\x18\x03 \x01(\tR\x05model\"\x7f\n" +
 	"\rQueryResponse\x12\x14\n" +
 	"\x05reply\x18\x01 \x01(\tR\x05reply\x12\x16\n" +
 	"\x06intent\x18\x02 \x01(\tR\x06intent\x12!\n" +
-	"\faction_taken\x18\x03 \x01(\bR\vactionTaken2?\n" +
+	"\faction_taken\x18\x03 \x01(\bR\vactionTaken\x12\x1d\n" +
+	"\n" +
+	"model_used\x18\x04 \x01(\tR\tmodelUsed\"\x13\n" +
+	"\x11ListModelsRequest\"*\n" +
+	"\x12ListModelsResponse\x12\x14\n" +
+	"\x05names\x18\x01 \x03(\tR\x05names2\x82\x01\n" +
 	"\tAIService\x122\n" +
-	"\x05Query\x12\x13.ai.v1.QueryRequest\x1a\x14.ai.v1.QueryResponseB4Z2gitea.nik4nao.com/nik/home-services/gen/ai/v1;aiv1b\x06proto3"
+	"\x05Query\x12\x13.ai.v1.QueryRequest\x1a\x14.ai.v1.QueryResponse\x12A\n" +
+	"\n" +
+	"ListModels\x12\x18.ai.v1.ListModelsRequest\x1a\x19.ai.v1.ListModelsResponseB4Z2gitea.nik4nao.com/nik/home-services/gen/ai/v1;aiv1b\x06proto3"
 
 var (
 	file_ai_v1_ai_proto_rawDescOnce sync.Once
@@ -160,16 +264,20 @@ func file_ai_v1_ai_proto_rawDescGZIP() []byte {
 	return file_ai_v1_ai_proto_rawDescData
 }
 
-var file_ai_v1_ai_proto_msgTypes = make([]protoimpl.MessageInfo, 2)
+var file_ai_v1_ai_proto_msgTypes = make([]protoimpl.MessageInfo, 4)
 var file_ai_v1_ai_proto_goTypes = []any{
 	(*QueryRequest)(nil),       // 0: ai.v1.QueryRequest
 	(*QueryResponse)(nil),      // 1: ai.v1.QueryResponse
+	(*ListModelsRequest)(nil),  // 2: ai.v1.ListModelsRequest
+	(*ListModelsResponse)(nil), // 3: ai.v1.ListModelsResponse
 }
 var file_ai_v1_ai_proto_depIdxs = []int32{
 	0, // 0: ai.v1.AIService.Query:input_type -> ai.v1.QueryRequest
-	1, // 1: ai.v1.AIService.Query:output_type -> ai.v1.QueryResponse
+	2, // 1: ai.v1.AIService.ListModels:input_type -> ai.v1.ListModelsRequest
-	1, // [1:2] is the sub-list for method output_type
+	1, // 2: ai.v1.AIService.Query:output_type -> ai.v1.QueryResponse
-	0, // [0:1] is the sub-list for method input_type
+	3, // 3: ai.v1.AIService.ListModels:output_type -> ai.v1.ListModelsResponse
+	2, // [2:4] is the sub-list for method output_type
+	0, // [0:2] is the sub-list for method input_type
 	0, // [0:0] is the sub-list for extension type_name
 	0, // [0:0] is the sub-list for extension extendee
 	0, // [0:0] is the sub-list for field type_name
@@ -186,7 +294,7 @@ func file_ai_v1_ai_proto_init() {
 			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
 			RawDescriptor: unsafe.Slice(unsafe.StringData(file_ai_v1_ai_proto_rawDesc), len(file_ai_v1_ai_proto_rawDesc)),
 			NumEnums:      0,
-			NumMessages:   2,
+			NumMessages:   4,
 			NumExtensions: 0,
 			NumServices:   1,
 		},

gen/ai/v1/ai_grpc.pb.go

@@ -20,6 +20,7 @@ const _ = grpc.SupportPackageIsVersion9
 
 const (
 	AIService_Query_FullMethodName      = "/ai.v1.AIService/Query"
+	AIService_ListModels_FullMethodName = "/ai.v1.AIService/ListModels"
 )
 
 // AIServiceClient is the client API for AIService service.
@@ -27,6 +28,7 @@ const (
 // For semantics around ctx use and closing/ending streaming RPCs, please refer to https://pkg.go.dev/google.golang.org/grpc/?tab=doc#ClientConn.NewStream.
 type AIServiceClient interface {
 	Query(ctx context.Context, in *QueryRequest, opts ...grpc.CallOption) (*QueryResponse, error)
+	ListModels(ctx context.Context, in *ListModelsRequest, opts ...grpc.CallOption) (*ListModelsResponse, error)
 }
 
 type aIServiceClient struct {
@@ -47,11 +49,22 @@ func (c *aIServiceClient) Query(ctx context.Context, in *QueryRequest, opts ...g
 	return out, nil
 }
 
+func (c *aIServiceClient) ListModels(ctx context.Context, in *ListModelsRequest, opts ...grpc.CallOption) (*ListModelsResponse, error) {
+	cOpts := append([]grpc.CallOption{grpc.StaticMethod()}, opts...)
+	out := new(ListModelsResponse)
+	err := c.cc.Invoke(ctx, AIService_ListModels_FullMethodName, in, out, cOpts...)
+	if err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
 // AIServiceServer is the server API for AIService service.
 // All implementations must embed UnimplementedAIServiceServer
 // for forward compatibility.
 type AIServiceServer interface {
 	Query(context.Context, *QueryRequest) (*QueryResponse, error)
+	ListModels(context.Context, *ListModelsRequest) (*ListModelsResponse, error)
 	mustEmbedUnimplementedAIServiceServer()
 }
 
@@ -65,6 +78,9 @@ type UnimplementedAIServiceServer struct{}
 func (UnimplementedAIServiceServer) Query(context.Context, *QueryRequest) (*QueryResponse, error) {
 	return nil, status.Error(codes.Unimplemented, "method Query not implemented")
 }
+func (UnimplementedAIServiceServer) ListModels(context.Context, *ListModelsRequest) (*ListModelsResponse, error) {
+	return nil, status.Error(codes.Unimplemented, "method ListModels not implemented")
+}
 func (UnimplementedAIServiceServer) mustEmbedUnimplementedAIServiceServer() {}
 func (UnimplementedAIServiceServer) testEmbeddedByValue()                   {}
 
@@ -104,6 +120,24 @@ func _AIService_Query_Handler(srv interface{}, ctx context.Context, dec func(int
 	return interceptor(ctx, in, info, handler)
 }
 
+func _AIService_ListModels_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
+	in := new(ListModelsRequest)
+	if err := dec(in); err != nil {
+		return nil, err
+	}
+	if interceptor == nil {
+		return srv.(AIServiceServer).ListModels(ctx, in)
+	}
+	info := &grpc.UnaryServerInfo{
+		Server:     srv,
+		FullMethod: AIService_ListModels_FullMethodName,
+	}
+	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
+		return srv.(AIServiceServer).ListModels(ctx, req.(*ListModelsRequest))
+	}
+	return interceptor(ctx, in, info, handler)
+}
+
 // AIService_ServiceDesc is the grpc.ServiceDesc for AIService service.
 // It's only intended for direct use with grpc.RegisterService,
 // and not to be introspected or modified (even as a copy)
@@ -115,6 +149,10 @@ var AIService_ServiceDesc = grpc.ServiceDesc{
 			MethodName: "Query",
 			Handler:    _AIService_Query_Handler,
 		},
+		{
+			MethodName: "ListModels",
+			Handler:    _AIService_ListModels_Handler,
+		},
 	},
 	Streams:  []grpc.StreamDesc{},
 	Metadata: "ai/v1/ai.proto",

proto/ai/v1/ai.proto

@@ -6,15 +6,24 @@ option go_package = "gitea.nik4nao.com/nik/home-services/gen/ai/v1;aiv1";
 
 service AIService {
   rpc Query(QueryRequest) returns (QueryResponse);
+  rpc ListModels(ListModelsRequest) returns (ListModelsResponse);
 }
 
 message QueryRequest {
   string text = 1;
   string source = 2;
+  string model = 3;
 }
 
 message QueryResponse {
   string reply = 1;
   string intent = 2;
   bool action_taken = 3;
+  string model_used = 4;
+}
+
+message ListModelsRequest {}
+
+message ListModelsResponse {
+  repeated string names = 1;
 }