fix: refresh agent config on send; widen fallback retry detection

- Refresh agent config from API before sending a message so edits
  in AgentBuilder (changed keyId/modelId/agentModels) take effect
  immediately on existing tabs instead of using stale snapshots
- Broaden isRetryable check to also match 'usage limit' and
  'exhausted' so fallback keys are actually tried on quota errors

2 files changed, 46 insertions, 2 deletions

diff --git a/packages/api/src/agent-manager.ts b/packages/api/src/agent-manager.ts
index 88503f3..9ed2f51 100644
--- a/packages/api/src/agent-manager.ts
+++ b/packages/api/src/agent-manager.ts
@@ -1248,7 +1248,9 @@ export class AgentManager {
 			const isRetryable =
 				attemptError.includes("status=429") ||
 				attemptError.toLowerCase().includes("rate limit") ||
-				attemptError.toLowerCase().includes("rate_limit");
+				attemptError.toLowerCase().includes("rate_limit") ||
+				attemptError.toLowerCase().includes("usage limit") ||
+				attemptError.toLowerCase().includes("exhausted");
 
 			if (isRetryable && this.modelRegistry && tabAgent.keyId) {
 				this.modelRegistry.markKeyExhausted(tabAgent.keyId, attemptError);
diff --git a/packages/frontend/src/lib/tabs.svelte.ts b/packages/frontend/src/lib/tabs.svelte.ts
index b2c4480..9b31b3f 100644
--- a/packages/frontend/src/lib/tabs.svelte.ts
+++ b/packages/frontend/src/lib/tabs.svelte.ts
@@ -1194,6 +1194,41 @@ export function createTabStore() {
 		}
 	}
 
+	async function refreshAgentConfig(tabId: string): Promise<void> {
+		const tab = getTabById(tabId);
+		if (!tab?.agentSlug || !tab.agentScope) return;
+		try {
+			const res = await fetch(`${config.apiBase}/agents`);
+			if (!res.ok) return;
+			const data = (await res.json()) as {
+				agents?: Array<{
+					slug: string;
+					scope: string;
+					models: Array<{ key_id: string; model_id: string }>;
+					cwd?: string;
+				}>;
+			};
+			const agents = data.agents ?? [];
+			const freshAgent = agents.find((a) => a.slug === tab.agentSlug && a.scope === tab.agentScope);
+			if (!freshAgent) return;
+			const firstModel = freshAgent.models[0];
+			const patch: Partial<Tab> = {
+				agentModels: freshAgent.models,
+				workingDirectory: freshAgent.cwd || null,
+			};
+			if (firstModel) {
+				patch.keyId = firstModel.key_id;
+				patch.modelId = firstModel.model_id;
+			} else {
+				patch.keyId = null;
+				patch.modelId = null;
+			}
+			updateTab(tabId, patch);
+		} catch {
+			// Silently fall back to stale values
+		}
+	}
+
 	async function fetchSkillContent(scope: string, name: string): Promise<string | null> {
 		try {
 			const res = await fetch(
@@ -1208,9 +1243,16 @@ export function createTabStore() {
 	}
 
 	async function sendMessage(text: string): Promise<void> {
-		const tab = getActiveTab();
+		let tab = getActiveTab();
 		if (!tab) return;
 
+		// Refresh agent config to pick up any changes made in AgentBuilder
+		if (tab.agentSlug && tab.agentScope) {
+			await refreshAgentConfig(tab.id);
+			tab = getActiveTab();
+			if (!tab) return;
+		}
+
 		// Fetch content for checked skills and build the message to send
 		let messageToSend = text;
 		const checkedKeys = Object.entries(appSettings.skillChecks)