fix(desktop): send provider currency in Meta to prevent session-start flip (#4546)

desktop/app.go

@@ -3403,6 +3403,7 @@ type Meta struct {
 	TokenMode         string `json:"tokenMode"`
 	Goal              string `json:"goal,omitempty"`
 	GoalStatus        string `json:"goalStatus,omitempty"`
+	Currency          string `json:"currency,omitempty"` // display currency symbol from provider pricing (e.g. "$", "¥")
 }
 
 // Meta reports the model label, readiness, any startup error, the working
@@ -3427,6 +3428,10 @@ func (a *App) MetaForTab(tabID string) Meta {
 	tokenMode := currentTabTokenMode(tab)
 	goal := currentTabGoal(tab)
 	goalStatus := currentTabGoalStatus(tab)
+	var currency string
+	if tab.Ctrl != nil {
+		currency = tab.Ctrl.CurrencySymbol()
+	}
 	return Meta{
 		Label:             tab.Label,
 		Ready:             tab.Ready,
@@ -3444,6 +3449,7 @@ func (a *App) MetaForTab(tabID string) Meta {
 		TokenMode:         tokenMode,
 		Goal:              goal,
 		GoalStatus:        goalStatus,
+		Currency:          currency,
 	}
 }
 

desktop/frontend/src/lib/types.ts

@@ -355,6 +355,7 @@ export interface Meta {
   tokenMode?: TokenMode;
   goal?: string;
   goalStatus?: GoalStatus;
+  currency?: string; // display currency symbol from provider pricing (e.g. "$", "¥")
 }
 
 export type CollaborationMode = "normal" | "plan" | "goal";

desktop/frontend/src/lib/useController.ts

@@ -178,7 +178,8 @@ export function sameMeta(a?: Meta, b?: Meta): boolean {
     a.toolApprovalMode === b.toolApprovalMode &&
     a.tokenMode === b.tokenMode &&
     a.goal === b.goal &&
-    a.goalStatus === b.goalStatus
+    a.goalStatus === b.goalStatus &&
+    a.currency === b.currency
   );
 }
 
@@ -639,7 +640,11 @@ export function reducer(s: State, a: Action): State {
       });
       return { ...s, items: finalized, running: false, turnActive: false, pendingPrompt, backgroundJobs, cancelRequested, cancellable, live: undefined, currentAssistant: undefined, approval: undefined, ask: undefined };
     }
-    case "meta": return sameMeta(s.meta, a.meta) ? s : { ...s, meta: a.meta };
+    case "meta": {
+      if (sameMeta(s.meta, a.meta)) return s;
+      const sessionCurrency = a.meta?.currency || s.sessionCurrency;
+      return { ...s, meta: a.meta, sessionCurrency };
+    }
     case "context": {
       const sessionTokens = typeof a.context.sessionTokens === "number"
         ? Math.max(0, a.context.sessionTokens)
@@ -669,7 +674,7 @@ export function reducer(s: State, a: Action): State {
     case "local_notice": return { ...s, running: false, turnActive: false, seq: s.seq + 1, items: [...s.items, { kind: "notice", id: `n${s.seq}`, level: a.level, text: a.text }] };
     case "clearApproval": return { ...s, approval: undefined, pendingPrompt: false };
     case "clearAsk": return { ...s, ask: undefined, pendingPrompt: false };
-    case "reset": return { ...initialState, meta: s.meta, context: { ...s.context, used: 0, sessionTokens: 0 }, balance: s.balance, effort: s.effort, jobs: s.jobs, sessionGen: s.sessionGen + 1 };
+    case "reset": return { ...initialState, meta: s.meta, sessionCurrency: s.sessionCurrency, context: { ...s.context, used: 0, sessionTokens: 0 }, balance: s.balance, effort: s.effort, jobs: s.jobs, sessionGen: s.sessionGen + 1 };
     case "event": return applyEvent(s, a.e);
     default: return s;
   }

desktop/tab_profile_test.go

@@ -446,6 +446,44 @@ func TestSetBypassPreservesPlanMode(t *testing.T) {
 	}
 }
 
+func TestMetaReportsCurrencyFromProvider(t *testing.T) {
+	isolateDesktopUserDirs(t)
+
+	app := NewApp()
+	tab := testTab("a", t.TempDir())
+	app.tabs = map[string]*WorkspaceTab{tab.ID: tab}
+	app.tabOrder = []string{tab.ID}
+	app.activeTabID = tab.ID
+	defer tab.Ctrl.Close()
+
+	// Default: no pricing configured → empty currency.
+	meta := app.MetaForTab(tab.ID)
+	if meta.Currency != "" {
+		t.Fatalf("default currency = %q, want empty", meta.Currency)
+	}
+
+	// Simulate a controller built with USD pricing (e.g. DeepSeek).
+	tab.Ctrl = control.New(control.Options{Label: "deepseek", CurrencySymbol: "$"})
+	meta = app.MetaForTab(tab.ID)
+	if meta.Currency != "$" {
+		t.Fatalf("USD currency = %q, want $", meta.Currency)
+	}
+
+	// Simulate a controller built with CNY pricing (e.g. MIMO).
+	tab.Ctrl = control.New(control.Options{Label: "mimo", CurrencySymbol: "¥"})
+	meta = app.MetaForTab(tab.ID)
+	if meta.Currency != "¥" {
+		t.Fatalf("CNY currency = %q, want ¥", meta.Currency)
+	}
+
+	// Nil controller (boot failed / tab still loading) → empty, no panic.
+	tab.Ctrl = nil
+	meta = app.MetaForTab(tab.ID)
+	if meta.Currency != "" {
+		t.Fatalf("nil ctrl currency = %q, want empty", meta.Currency)
+	}
+}
+
 func userConfigPathForTest() string {
 	if dir, err := os.UserConfigDir(); err == nil {
 		return dir + "/reasonix/reasonix.toml"

internal/boot/boot.go

@@ -823,6 +823,7 @@ func Build(ctx context.Context, opts Options) (*control.Controller, error) {
 		DisableColdResumePrune: !cfg.ColdResumePruneEnabled(),
 		Shell:                  shell,
 		PlanModeAllowedTools:   cfg.Agent.PlanModeAllowedTools,
+		CurrencySymbol:         entry.Price.Symbol(),
 		OnRemember: func(rule string) control.RememberResult {
 			return rememberPermissionRule(root, rule)
 		},

internal/control/controller.go

@@ -64,6 +64,7 @@ type Controller struct {
 
 	label             string
 	modelRef          string
+	currencySymbol    string // display currency symbol from provider pricing (e.g. "$", "¥"); empty = default "¥"
 	systemPrompt      string
 	sessionDir        string
 	host              *plugin.Host
@@ -287,6 +288,10 @@ type Options struct {
 	// matches the agent's configured [tools.shell] choice. Zero value = auto.
 	Shell      sandbox.Shell
 	Classifier autoPlanClassifier
+	// CurrencySymbol is the display currency symbol from the provider's pricing
+	// configuration (e.g. "$" for USD, "¥" for CNY). Empty means no pricing was
+	// configured and the frontend should use its default.
+	CurrencySymbol string
 	// OnRemember, when set, is invoked with a new allow rule the user chose to
 	// persist to disk (e.g. "Bash(go test:*)"). The callback is wired into the
 	// permission Gate on EnableInteractiveApproval.
@@ -334,6 +339,7 @@ func New(opts Options) *Controller {
 		disableColdResumePrune: opts.DisableColdResumePrune,
 		shell:                  opts.Shell,
 		classifier:             classifier,
+		currencySymbol:         opts.CurrencySymbol,
 		onRemember:             opts.OnRemember,
 		balanceURL:             opts.BalanceURL,
 		balanceKey:             opts.BalanceKey,
@@ -2581,6 +2587,11 @@ func (c *Controller) DisconnectMCPServer(name string) bool {
 // Label returns the human-readable model label, e.g. "deepseek-flash".
 func (c *Controller) Label() string { return c.label }
 
+// CurrencySymbol returns the display currency symbol from the provider's
+// pricing configuration (e.g. "$" for USD, "¥" for CNY). Empty means the
+// provider had no pricing configured and the frontend should use its default.
+func (c *Controller) CurrencySymbol() string { return c.currencySymbol }
+
 // WorkspaceRoot returns the workspace root for this controller's session
 // (the directory that file-writers and @-references are scoped to).
 // Empty means no scoping is in effect.