Fix model name display in TUI sidebar for all model types

pkg/model/provider/rulebased/client.go

@@ -41,9 +41,10 @@ type ProviderFactory func(ctx context.Context, modelSpec string, models map[stri
 // Client implements the Provider interface for rule-based model routing.
 type Client struct {
 	base.Config
-	routes   []Provider
-	fallback Provider
-	index    bleve.Index
+	routes         []Provider
+	fallback       Provider
+	index          bleve.Index
+	lastSelectedID string // ID of the provider selected by the most recent call
 }
 
 // NewClient creates a new rule-based routing client.
@@ -152,6 +153,7 @@ func filterOutMaxTokens(opts []options.Opt) []options.Opt {
 }
 
 // CreateChatCompletionStream selects a provider based on input and delegates the call.
+// The selected provider's ID is recorded in LastSelectedModelID.
 func (c *Client) CreateChatCompletionStream(
 	ctx context.Context,
 	messages []chat.Message,
@@ -162,15 +164,23 @@ func (c *Client) CreateChatCompletionStream(
 		return nil, errors.New("no provider available for routing")
 	}
 
+	c.lastSelectedID = provider.ID()
 	slog.Debug("Rule-based router selected model",
 		"router", c.ID(),
-		"selected_model", provider.ID(),
+		"selected_model", c.lastSelectedID,
 		"message_count", len(messages),
 	)
 
 	return provider.CreateChatCompletionStream(ctx, messages, availableTools)
 }
 
+// LastSelectedModelID returns the ID of the provider selected by the most
+// recent CreateChatCompletionStream call. This allows callers to display
+// the YAML-configured sub-model name for rule-based routing.
+func (c *Client) LastSelectedModelID() string {
+	return c.lastSelectedID
+}
+
 // selectProvider finds the best matching provider for the messages.
 // Bleve returns hits sorted by score, so the top hit determines the route.
 func (c *Client) selectProvider(messages []chat.Message) Provider {

pkg/runtime/fallback.go

@@ -283,6 +283,15 @@ func (r *LocalRuntime) tryModelWithFallback(
 
 			// Stream created successfully, now handle it
 			slog.Debug("Processing stream", "agent", a.Name(), "model", modelEntry.provider.ID())
+
+			// If the provider is a rule-based router, notify the sidebar
+			// of the selected sub-model's YAML-configured name.
+			if rp, ok := modelEntry.provider.(interface{ LastSelectedModelID() string }); ok {
+				if selected := rp.LastSelectedModelID(); selected != "" {
+					events <- AgentInfo(a.Name(), selected, a.Description(), a.WelcomeMessage())
+				}
+			}
+
 			res, err := r.handleStream(ctx, stream, a, agentTools, sess, m, events)
 			if err != nil {
 				lastErr = err

pkg/runtime/loop.go

@@ -1,7 +1,6 @@
 package runtime
 
 import (
-	"cmp"
 	"context"
 	"errors"
 	"fmt"
@@ -86,10 +85,6 @@ func (r *LocalRuntime) RunStream(ctx context.Context, sess *session.Session) <-c
 
 		a := r.resolveSessionAgent(sess)
 
-		// Emit agent information for sidebar display
-		// Use getEffectiveModelID to account for active fallback cooldowns
-		events <- AgentInfo(a.Name(), r.getEffectiveModelID(a), a.Description(), a.WelcomeMessage())
-
 		// Emit team information
 		events <- TeamInfo(r.agentDetailsFromTeam(), a.Name())
 
@@ -210,7 +205,6 @@ func (r *LocalRuntime) RunStream(ctx context.Context, sess *session.Session) <-c
 			))
 
 			model := a.Model()
-			defaultModelID := r.getEffectiveModelID(a)
 
 			// Per-tool model routing: use a cheaper model for this turn
 			// if the previous tool calls specified one, then reset.
@@ -236,10 +230,10 @@ func (r *LocalRuntime) RunStream(ctx context.Context, sess *session.Session) <-c
 
 			modelID := model.ID()
 
-			// Notify sidebar when this turn uses a different model (per-tool override).
-			if modelID != defaultModelID {
-				events <- AgentInfo(a.Name(), modelID, a.Description(), a.WelcomeMessage())
-			}
+			// Notify sidebar of the model for this turn. For rule-based
+			// routing, the actual routed model is emitted from within the
+			// stream once the first chunk arrives.
+			events <- AgentInfo(a.Name(), modelID, a.Description(), a.WelcomeMessage())
 
 			slog.Debug("Using agent", "agent", a.Name(), "model", modelID)
 			slog.Debug("Getting model definition", "model_id", modelID)
@@ -311,16 +305,9 @@ func (r *LocalRuntime) RunStream(ctx context.Context, sess *session.Session) <-c
 				return
 			}
 
-			// Update sidebar model info to reflect what was actually used this turn.
-			// Fallback models are sticky (cooldown system persists them), so we only
-			// emit once. Per-tool model overrides are temporary (one turn), so we
-			// emit the override and then revert to the agent's default.
 			if usedModel != nil && usedModel.ID() != model.ID() {
 				slog.Info("Used fallback model", "agent", a.Name(), "primary", model.ID(), "used", usedModel.ID())
 				events <- AgentInfo(a.Name(), usedModel.ID(), a.Description(), a.WelcomeMessage())
-			} else if model.ID() != defaultModelID {
-				// Per-tool override was active: revert sidebar to the agent's default model.
-				events <- AgentInfo(a.Name(), defaultModelID, a.Description(), a.WelcomeMessage())
 			}
 			streamSpan.SetAttributes(
 				attribute.Int("tool.calls", len(res.Calls)),
@@ -410,7 +397,7 @@ func (r *LocalRuntime) recordAssistantMessage(
 			float64(res.Usage.CacheWriteTokens)*m.Cost.CacheWrite) / 1e6
 	}
 
-	messageModel := cmp.Or(res.ActualModel, modelID)
+	messageModel := modelID
 
 	assistantMessage := chat.Message{
 		Role:              chat.MessageRoleAssistant,

pkg/runtime/runtime_test.go

@@ -276,12 +276,12 @@ func TestSimple(t *testing.T) {
 	require.Equal(t, chat.MessageRoleAssistant, msgAdded.Message.Message.Role)
 
 	expectedEvents := []Event{
-		AgentInfo("root", "test/mock-model", "", ""),
 		TeamInfo([]AgentDetails{{Name: "root", Provider: "test", Model: "mock-model"}}, "root"),
 		ToolsetInfo(0, false, "root"),
 		UserMessage("Hi", sess.ID, nil, 0),
 		StreamStarted(sess.ID, "root"),
 		ToolsetInfo(0, false, "root"),
+		AgentInfo("root", "test/mock-model", "", ""),
 		AgentChoice("root", sess.ID, "Hello"),
 		MessageAdded(sess.ID, msgAdded.Message, "root"),
 		NewTokenUsageEvent(sess.ID, "root", &Usage{InputTokens: 3, OutputTokens: 2, ContextLength: 5, LastMessage: &MessageUsage{
@@ -315,12 +315,12 @@ func TestMultipleContentChunks(t *testing.T) {
 	require.NotNil(t, msgAdded.Message)
 
 	expectedEvents := []Event{
-		AgentInfo("root", "test/mock-model", "", ""),
 		TeamInfo([]AgentDetails{{Name: "root", Provider: "test", Model: "mock-model"}}, "root"),
 		ToolsetInfo(0, false, "root"),
 		UserMessage("Please greet me", sess.ID, nil, 0),
 		StreamStarted(sess.ID, "root"),
 		ToolsetInfo(0, false, "root"),
+		AgentInfo("root", "test/mock-model", "", ""),
 		AgentChoice("root", sess.ID, "Hello "),
 		AgentChoice("root", sess.ID, "there, "),
 		AgentChoice("root", sess.ID, "how "),
@@ -356,12 +356,12 @@ func TestWithReasoning(t *testing.T) {
 	require.NotNil(t, msgAdded.Message)
 
 	expectedEvents := []Event{
-		AgentInfo("root", "test/mock-model", "", ""),
 		TeamInfo([]AgentDetails{{Name: "root", Provider: "test", Model: "mock-model"}}, "root"),
 		ToolsetInfo(0, false, "root"),
 		UserMessage("Hi", sess.ID, nil, 0),
 		StreamStarted(sess.ID, "root"),
 		ToolsetInfo(0, false, "root"),
+		AgentInfo("root", "test/mock-model", "", ""),
 		AgentChoiceReasoning("root", sess.ID, "Let me think about this..."),
 		AgentChoiceReasoning("root", sess.ID, " I should respond politely."),
 		AgentChoice("root", sess.ID, "Hello, how can I help you?"),
@@ -396,12 +396,12 @@ func TestMixedContentAndReasoning(t *testing.T) {
 	require.NotNil(t, msgAdded.Message)
 
 	expectedEvents := []Event{
-		AgentInfo("root", "test/mock-model", "", ""),
 		TeamInfo([]AgentDetails{{Name: "root", Provider: "test", Model: "mock-model"}}, "root"),
 		ToolsetInfo(0, false, "root"),
 		UserMessage("Hi there", sess.ID, nil, 0),
 		StreamStarted(sess.ID, "root"),
 		ToolsetInfo(0, false, "root"),
+		AgentInfo("root", "test/mock-model", "", ""),
 		AgentChoiceReasoning("root", sess.ID, "The user wants a greeting"),
 		AgentChoice("root", sess.ID, "Hello!"),
 		AgentChoiceReasoning("root", sess.ID, " I should be friendly"),
@@ -454,12 +454,12 @@ func TestErrorEvent(t *testing.T) {
 	}
 
 	require.Len(t, events, 8)
-	require.IsType(t, &AgentInfoEvent{}, events[0])
-	require.IsType(t, &TeamInfoEvent{}, events[1])
-	require.IsType(t, &ToolsetInfoEvent{}, events[2])
-	require.IsType(t, &UserMessageEvent{}, events[3])
-	require.IsType(t, &StreamStartedEvent{}, events[4])
-	require.IsType(t, &ToolsetInfoEvent{}, events[5])
+	require.IsType(t, &TeamInfoEvent{}, events[0])
+	require.IsType(t, &ToolsetInfoEvent{}, events[1])
+	require.IsType(t, &UserMessageEvent{}, events[2])
+	require.IsType(t, &StreamStartedEvent{}, events[3])
+	require.IsType(t, &ToolsetInfoEvent{}, events[4])
+	require.IsType(t, &AgentInfoEvent{}, events[5])
 	require.IsType(t, &ErrorEvent{}, events[6])
 	require.IsType(t, &StreamStoppedEvent{}, events[7])
 
@@ -493,12 +493,11 @@ func TestContextCancellation(t *testing.T) {
 		events = append(events, ev)
 	}
 
-	require.GreaterOrEqual(t, len(events), 5)
-	require.IsType(t, &AgentInfoEvent{}, events[0])
-	require.IsType(t, &TeamInfoEvent{}, events[1])
-	require.IsType(t, &ToolsetInfoEvent{}, events[2])
-	require.IsType(t, &UserMessageEvent{}, events[3])
-	require.IsType(t, &StreamStartedEvent{}, events[4])
+	require.GreaterOrEqual(t, len(events), 4)
+	require.IsType(t, &TeamInfoEvent{}, events[0])
+	require.IsType(t, &ToolsetInfoEvent{}, events[1])
+	require.IsType(t, &UserMessageEvent{}, events[2])
+	require.IsType(t, &StreamStartedEvent{}, events[3])
 	require.IsType(t, &StreamStoppedEvent{}, events[len(events)-1])
 }
 

pkg/runtime/streaming.go

@@ -26,7 +26,6 @@ type streamResult struct {
 	ThinkingSignature string
 	ThoughtSignature  []byte
 	Stopped           bool
-	ActualModel       string
 	Usage             *chat.Usage
 	RateLimit         *chat.RateLimit
 }
@@ -43,7 +42,6 @@ func (r *LocalRuntime) handleStream(ctx context.Context, stream chat.MessageStre
 	var thinkingSignature string
 	var thoughtSignature []byte
 	var toolCalls []tools.ToolCall
-	var actualModel string
 	var messageUsage *chat.Usage
 	var messageRateLimit *chat.RateLimit
 
@@ -102,11 +100,6 @@ func (r *LocalRuntime) handleStream(ctx context.Context, stream chat.MessageStre
 			thoughtSignature = choice.Delta.ThoughtSignature
 		}
 
-		// Capture the actual model from the stream response (useful for model routing)
-		if actualModel == "" && response.Model != "" {
-			actualModel = response.Model
-		}
-
 		if choice.FinishReason == chat.FinishReasonStop || choice.FinishReason == chat.FinishReasonLength {
 			recordUsage()
 			return streamResult{
@@ -116,7 +109,6 @@ func (r *LocalRuntime) handleStream(ctx context.Context, stream chat.MessageStre
 				ThinkingSignature: thinkingSignature,
 				ThoughtSignature:  thoughtSignature,
 				Stopped:           true,
-				ActualModel:       actualModel,
 				Usage:             messageUsage,
 				RateLimit:         messageRateLimit,
 			}, nil
@@ -191,7 +183,6 @@ func (r *LocalRuntime) handleStream(ctx context.Context, stream chat.MessageStre
 		ThinkingSignature: thinkingSignature,
 		ThoughtSignature:  thoughtSignature,
 		Stopped:           stoppedDueToNoOutput,
-		ActualModel:       actualModel,
 		Usage:             messageUsage,
 		RateLimit:         messageRateLimit,
 	}, nil

pkg/tui/components/sidebar/sidebar.go

@@ -268,8 +268,13 @@ func checkReasoningSupportCmd(ctx context.Context, modelID string) tea.Cmd {
 	}
 }
 
-// SetAgentInfo sets the current agent information and updates the model in availableAgents
+// SetAgentInfo sets the current agent information and updates the model in availableAgents.
+// It no-ops when the values are unchanged to avoid unnecessary cache invalidation and re-renders.
 func (m *model) SetAgentInfo(agentName, modelID, description string) tea.Cmd {
+	if m.currentAgent == agentName && m.agentModel == modelID && m.agentDescription == description {
+		return nil
+	}
+
 	m.currentAgent = agentName
 	m.agentModel = modelID
 	m.agentDescription = description