Preserve and display the generating model for each assistant reply

web/tests/message-generation.test.mjs

@@ -0,0 +1,15 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+import { getMessageGenerationLabel } from "../src/lib/message-generation.ts";
+
+test("reply labels use the recorded provider and model", () => {
+  for (const [provider, label] of [["openai", "OpenAI"], ["anthropic", "Anthropic"], ["xai", "xAI"], ["gemini", "Gemini"], ["hermes-agent", "Hermes Agent"]]) {
+    assert.equal(getMessageGenerationLabel({ role: "assistant", metadata: { generation: { provider, model: "original-model" } } }), `${label} · original-model`);
+  }
+});
+
+test("missing or malformed attribution stays unknown and Agent asides keep their identity", () => {
+  for (const metadata of [null, [], {}, { provider: "openai", model: "unrelated" }, { generation: { provider: "unknown", model: "model" } }, { generation: { provider: "openai", model: "" } }, { generation: { provider: "openai", model: [] } }, { generation: { provider: "openai", model: "model" }, agentAside: true }]) {
+    assert.equal(getMessageGenerationLabel({ role: "assistant", metadata }), null);
+  }
+});

web/tests/mobile-workspace.browser.mjs

@@ -26,7 +26,7 @@ const markdown = [
 const chat = { id: "mobile-chat", title: "Mobile QA conversation with a long title", parentChatId: null, titleGenerationPending: false,
   createdAt: date, updatedAt: date, starred: false, starredAt: null, initiatedProvider: "openai", initiatedModel: "mobile-model-one",
   lastUsedProvider: "openai", lastUsedModel: "mobile-model-one", additionalSystemPrompt: null, enabledTools: [],
-  messages: [{ id: "mobile-assistant", role: "assistant", content: markdown, createdAt: date, name: null, metadata: null }] };
+  messages: [{ id: "mobile-assistant", role: "assistant", content: markdown, createdAt: date, name: null, metadata: { generation: { provider: "openai", model: "mobile-model-one" } } }] };
 const idle = { state: "idle", isThinking: false, queued: 0, backgroundWorkers: 0, tools: [], queuedMessages: [] };
 const errors = [], calls = [], forkRequests = [];
 let forkedChat;
@@ -119,6 +119,7 @@ async function checkFooterAlignment() {
   assert.notEqual(layout.dateColor, layout.paragraphColor, "timestamp uses secondary color");
   assert.equal(await footer.locator("time").getAttribute("datetime"), date);
   assert.match(await footer.locator("time").textContent(), /2026/);
+  assert.equal(await footer.locator("[data-message-generation]").textContent(), "OpenAI · mobile-model-one");
 }
 try {
   await page.goto(target.href, { waitUntil: "networkidle" });
@@ -261,6 +262,23 @@ try {
     const viewport = await page.locator('meta[name="viewport"]').getAttribute("content");
     assert.match(viewport, /user-scalable=no/);
     assert.match(viewport, /maximum-scale=1\.0(?:,|$)/);
+    // A mixed-model history keeps each attribution after reload, including unknown old replies.
+    const longModel = "claude-" + "long-model-identifier-".repeat(8);
+    chat.messages.push(
+      { ...chat.messages[0], id: "second-assistant", content: "A reply from a different provider.", metadata: { generation: { provider: "anthropic", model: longModel } } },
+      { ...chat.messages[0], id: "legacy-assistant", content: "A reply with no generation record.", metadata: null },
+    );
+    await page.reload({ waitUntil: "networkidle" });
+    await page.getByRole("heading", { name: chat.title, exact: true }).waitFor();
+    assert.deepEqual(await page.locator("main [data-message-generation]").allTextContents(), ["OpenAI · mobile-model-one", `Anthropic · ${longModel}`, "Model not recorded"]);
+    for (const width of [320, 390, 1280]) {
+      await page.setViewportSize({ width, height: 844 });
+      if (width < 768) await page.waitForFunction(() => document.querySelector(".workspace-sidebar").getBoundingClientRect().right <= 1);
+      await page.locator('[data-assistant-footer="second-assistant"]').evaluate(el => el.scrollIntoView({ block: "center" }));
+      assert.ok(await page.locator('[data-assistant-footer="second-assistant"]').evaluate(el => el.scrollWidth <= el.clientWidth), "long model identifier wraps within the footer");
+      assert.equal(await page.evaluate(() => document.documentElement.scrollWidth > innerWidth), false, `${width}px model-label overflow`);
+      if (artifactDir) await page.screenshot({ path: `${artifactDir}/mixed-models-${width}.png` });
+    }
     await page.setViewportSize({ width: 390, height: 844 });
     await page.waitForFunction(() => document.querySelector(".workspace-sidebar").getBoundingClientRect().right <= 1);
     await drag(300, 8, -160);