Merge branch 'dev' into u3/agent-effort-level

# Conflicts:
#	packages/api/tests/agent-manager.test.ts

3 files changed, 58 insertions, 4 deletions

diff --git a/packages/api/src/agent-manager.ts b/packages/api/src/agent-manager.ts
index d03e696..d339fbd 100644
--- a/packages/api/src/agent-manager.ts
+++ b/packages/api/src/agent-manager.ts
@@ -36,6 +36,7 @@ import {
 	getMessagesForTab,
 	getSetting,
 	getTab,
+	getUsageStatsForTab,
 	listOpenTabs,
 	loadAgent,
 	loadAgents,
@@ -56,6 +57,8 @@ import {
 	TaskList,
 	toAvailableSubagents,
 	toAvailableUserAgents,
+	type UsageData,
+	type UsageStats,
 	validateConfig,
 } from "@dispatch/core";
 import type { PermissionManager } from "./permission-manager.js";
@@ -1483,6 +1486,10 @@ export class AgentManager {
 			// turn (text / thinking / tool-batch / error / system), folded from
 			// the stream via the shared `appendEventToChunks` helper.
 			const chunks: Chunk[] = [];
+			// Per-attempt usage accumulator. Reset each fallback attempt so a
+			// superseded (rate-limited) attempt's usage is discarded alongside its
+			// `chunks`. One `usage` event → one UsageData row.
+			const usageRows: UsageData[] = [];
 			const assistantId = crypto.randomUUID();
 			let assistantPersisted = false;
 			tabAgent.currentChunks = chunks;
@@ -1493,8 +1500,17 @@ export class AgentManager {
 			// `tool-batch` into separate `tool_call` + `tool_result` rows and
 			// tags every row with `turn_id` + derived `step`.
 			const flushAssistant = (): void => {
-				if (assistantPersisted || chunks.length === 0) return;
-				appendChunks(tabId, explodeTurn(turnId, chunks));
+				if (assistantPersisted) return;
+				// Append usage as extra drafts in the SAME appendChunks call as the
+				// turn's content rows: one atomic write, one fsync, contiguous seqs.
+				// Usage rows are an invisible side channel (excluded from
+				// getChunksForTab); `step` is cosmetic for usage (never grouped).
+				const drafts = explodeTurn(turnId, chunks);
+				for (const u of usageRows) {
+					drafts.push({ turnId, step: 0, role: "assistant", type: "usage", data: u });
+				}
+				if (drafts.length === 0) return;
+				appendChunks(tabId, drafts);
 				assistantPersisted = true;
 			};
 
@@ -1548,6 +1564,15 @@ export class AgentManager {
 						allOutput += event.delta;
 					}
 
+					// Capture per-step usage as a side-channel row to persist with the
+					// turn (one row per `usage` event). The live `this.emit(event)`
+					// above still drives in-session accumulation; this is the reload-
+					// persistence path. `appendEventToChunks` intentionally ignores
+					// `usage`, so it never becomes message content.
+					if (event.type === "usage") {
+						usageRows.push({ ...event.usage });
+					}
+
 					// Route every content-bearing event through the shared helper.
 					// `appendEventToChunks` ignores lifecycle events (status / done
 					// / task-list-update / tab-created / message-* / etc), so it's
@@ -1622,7 +1647,16 @@ export class AgentManager {
 		// above). Signal the frontend that the turn's rows — with real seqs — are
 		// durable so it can fold its live representation into the sealed log.
 		// Emitted AFTER status:idle/error (which fire before the DB write).
-		this.emit({ type: "turn-sealed", turnId }, tabId);
+		// Carry the authoritative usage aggregate (read AFTER the usage rows were
+		// persisted) so the frontend reconciles its live cacheStats to the DB truth
+		// — self-healing the live overshoot from a discarded rate-limited attempt.
+		let usageStats: UsageStats | null = null;
+		try {
+			usageStats = getUsageStatsForTab(tabId);
+		} catch {
+			// DB read failed — omit reconciliation rather than crash the turn.
+		}
+		this.emit({ type: "turn-sealed", turnId, usageStats }, tabId);
 
 		// Turn fully settled — clear the shared turn id.
 		tabAgent.currentTurnId = null;
diff --git a/packages/api/src/routes/models.ts b/packages/api/src/routes/models.ts
index 03c079a..6a0f5dc 100644
--- a/packages/api/src/routes/models.ts
+++ b/packages/api/src/routes/models.ts
@@ -17,6 +17,7 @@ import {
 	listStoredCredentials,
 	refreshAccountCredentialsAsync,
 	resolveApiKey,
+	resolveContextLimit,
 	setApiKey,
 	validateAccountCredentials,
 } from "@dispatch/core";
@@ -161,6 +162,21 @@ modelsRoutes.get("/available", async (c) => {
 	return c.json({ models });
 });
 
+// Resolve a model's MAXIMUM context window (in tokens) from the models.dev
+// catalog. Returns `{ contextLimit: number | null }`; `null` means the model's
+// limit is unknown (unsupported provider, unknown model, or catalog offline),
+// which the frontend renders without a denominator/percentage.
+modelsRoutes.get("/context-limit", async (c) => {
+	const provider = c.req.query("provider");
+	const modelId = c.req.query("modelId");
+	if (!provider || !modelId) {
+		return c.json({ error: "provider and modelId query parameters are required" }, 400);
+	}
+
+	const contextLimit = await resolveContextLimit(provider, modelId);
+	return c.json({ contextLimit });
+});
+
 // List available Claude accounts with validated credentials
 modelsRoutes.get("/claude-accounts", async (c) => {
 	const candidates = resolveClaudeAccounts();
diff --git a/packages/api/src/routes/tabs.ts b/packages/api/src/routes/tabs.ts
index b1e9659..f52ee99 100644
--- a/packages/api/src/routes/tabs.ts
+++ b/packages/api/src/routes/tabs.ts
@@ -6,6 +6,7 @@ import {
 	getSetting,
 	getTab,
 	getTotalChunkCount,
+	getUsageStatsForTab,
 	groupRowsToMessages,
 	listOpenTabs,
 	setSetting,
@@ -27,7 +28,10 @@ export function setTabsAgentManager(
 }
 
 tabsRoutes.get("/", (c) => {
-	const tabs = listOpenTabs();
+	// Enrich each tab with its persisted usage aggregate so the frontend can
+	// seed `cacheStats` on reload without an extra round-trip. N small indexed
+	// queries — fine for tab counts.
+	const tabs = listOpenTabs().map((t) => ({ ...t, usageStats: getUsageStatsForTab(t.id) }));
 	return c.json({ tabs });
 });