fix(chat): show requested and actual reply models

Show requested and actual reply models in chat labels when fallback or provider routing changes the responding model.

routes/chat_helpers.py

@@ -774,7 +774,19 @@ def save_assistant_response(
 ):
     """Add assistant response to session history. In incognito mode, keeps in-memory context but skips DB persistence."""
     md = dict(last_metrics) if last_metrics else {}
-    md["model"] = sess.model
+    def _model_value(value) -> str:
+        if value is None:
+            return ""
+        if not isinstance(value, str):
+            value = str(value)
+        return value.strip()
+
+    requested_model = _model_value(md.get("requested_model") or md.get("selected_model") or getattr(sess, "model", ""))
+    actual_model = _model_value(md.get("model") or md.get("actual_model") or requested_model)
+    if requested_model:
+        md["requested_model"] = requested_model
+    if actual_model:
+        md["model"] = actual_model
     if character_name:
         md["character_name"] = character_name
     if web_sources:

routes/chat_routes.py

@@ -893,6 +893,8 @@ def setup_chat_routes(
             elif chat_mode == "chat":
                 _chat_start = time.time()
                 _answered_by = None  # set if the selected model failed and a fallback answered
+                _requested_model = sess.model
+                _actual_model = None
                 # ── Chat mode: call stream_llm directly, NO tools, NO document access ──
                 try:
                     _chat_candidates = [(sess.endpoint_url, sess.model, sess.headers)] + _fallback_candidates
@@ -925,10 +927,18 @@ def setup_chat_routes(
                                     # Selected model failed; a fallback answered.
                                     # Forward the notice and remember the real model.
                                     _answered_by = data.get("answered_by") or _answered_by
+                                    _actual_model = _actual_model or _answered_by
+                                    data["selected_model"] = data.get("selected_model") or _requested_model
                                     yield chunk
+                                elif data.get("type") == "model_actual":
+                                    _actual_model = data.get("model") or _actual_model
+                                    data["requested_model"] = _requested_model
+                                    yield f'data: {json.dumps(data)}\n\n'
                                 elif data.get("type") == "usage":
                                     last_metrics = data.get("data", {})
-                                    last_metrics["model"] = _answered_by or sess.model
+                                    _reported_model = last_metrics.get("model")
+                                    last_metrics["requested_model"] = _requested_model
+                                    last_metrics["model"] = _reported_model or _actual_model or _answered_by or _requested_model
                                     if ctx.context_length and last_metrics.get("input_tokens"):
                                         pct = min(round((last_metrics["input_tokens"] / ctx.context_length) * 100, 1), 100.0)
                                         last_metrics["context_percent"] = pct
@@ -965,7 +975,8 @@ def setup_chat_routes(
                                     "tokens_per_second": _tps,
                                     "context_percent": _ctx_pct,
                                     "context_length": ctx.context_length,
-                                    "model": sess.model,
+                                    "model": _actual_model or _answered_by or _requested_model,
+                                    "requested_model": _requested_model,
                                     "usage_source": "estimated",
                                 }
                                 yield f'data: {json.dumps({"type": "metrics", "data": last_metrics})}\n\n'
@@ -994,7 +1005,14 @@ def setup_chat_routes(
                 except (asyncio.CancelledError, GeneratorExit):
                     if full_response:
                         logger.info("Client disconnected mid-stream (chat mode) for session %s, saving partial (%d chars)", session, len(full_response))
-                        _stopped_content, _stopped_md = clean_thinking_for_save(full_response, {"stopped": True, "model": sess.model})
+                        _stopped_content, _stopped_md = clean_thinking_for_save(
+                            full_response,
+                            {
+                                "stopped": True,
+                                "model": _actual_model or _answered_by or _requested_model,
+                                "requested_model": _requested_model,
+                            },
+                        )
                         sess.add_message(ChatMessage("assistant", _stopped_content, metadata=_stopped_md))
                         if not incognito:
                             session_manager.save_sessions()
@@ -1006,6 +1024,8 @@ def setup_chat_routes(
                 _agent_rounds = 0
                 _agent_tool_calls = 0
                 _answered_by = None  # set if the selected model failed and a fallback answered
+                _requested_model = sess.model
+                _actual_model = None
                 try:
                     from src.settings import get_setting
                     from src.agent_tools import MAX_AGENT_ROUNDS as _DEFAULT_ROUNDS
@@ -1071,10 +1091,18 @@ def setup_chat_routes(
                                     # model so metrics reflect it, not the masked
                                     # selected model.
                                     _answered_by = data.get("answered_by") or _answered_by
+                                    _actual_model = _actual_model or _answered_by
+                                    data["selected_model"] = data.get("selected_model") or _requested_model
                                     yield chunk
+                                elif data.get("type") == "model_actual":
+                                    _actual_model = data.get("model") or _actual_model
+                                    data["requested_model"] = _requested_model
+                                    yield f'data: {json.dumps(data)}\n\n'
                                 elif data.get("type") == "metrics":
                                     last_metrics = data.get("data", {})
-                                    last_metrics["model"] = _answered_by or sess.model
+                                    _reported_model = last_metrics.get("model")
+                                    last_metrics["requested_model"] = last_metrics.get("requested_model") or _requested_model
+                                    last_metrics["model"] = _reported_model or _actual_model or _answered_by or _requested_model
                                     yield f'data: {json.dumps({"type": "metrics", "data": last_metrics})}\n\n'
                             except json.JSONDecodeError:
                                 yield chunk
@@ -1115,7 +1143,14 @@ def setup_chat_routes(
                     try:
                         if full_response:
                             logger.info("Client disconnected mid-stream for session %s, saving partial response (%d chars)", session, len(full_response))
-                            _stopped_content2, _stopped_md2 = clean_thinking_for_save(full_response, {"stopped": True, "model": sess.model})
+                            _stopped_content2, _stopped_md2 = clean_thinking_for_save(
+                                full_response,
+                                {
+                                    "stopped": True,
+                                    "model": _actual_model or _answered_by or _requested_model,
+                                    "requested_model": _requested_model,
+                                },
+                            )
                             sess.add_message(ChatMessage("assistant", _stopped_content2, metadata=_stopped_md2))
                             if not incognito:
                                 session_manager.save_sessions()

src/agent_loop.py

@@ -1741,6 +1741,8 @@ async def stream_agent_loop(
     has_real_usage = False
     backend_gen_tps = 0      # backend-reported true gen speed (llama.cpp timings)
     backend_prefill_tps = 0  # backend-reported prefill speed
+    requested_model = model
+    actual_model = model
     total_tool_calls = 0  # for budget enforcement
 
     # Loop-breaker state. Small models (e.g. deepseek-v4-flash) can get
@@ -1913,6 +1915,7 @@ async def stream_agent_loop(
                         logger.info(f"Agent round {round_num}: received {len(native_tool_calls)} native tool call(s)")
                     elif data.get("type") == "usage":
                         u = data.get("data", {})
+                        actual_model = u.get("model") or actual_model
                         round_input = u.get("input_tokens", 0)
                         real_input_tokens += round_input
                         real_output_tokens += u.get("output_tokens", 0)
@@ -1929,9 +1932,14 @@ async def stream_agent_loop(
                     elif data.get("type") == "fallback":
                         # The selected model failed and another answered; surface
                         # the notice so a misconfigured provider isn't masked.
+                        actual_model = data.get("answered_by") or actual_model
                         logger.warning(f"[agent] round {round_num} fell back: "
                                        f"{data.get('selected_model')} -> {data.get('answered_by')}")
                         yield chunk
+                    elif data.get("type") == "model_actual":
+                        actual_model = data.get("model") or actual_model
+                        data["requested_model"] = requested_model
+                        yield f"data: {json.dumps(data)}\n\n"
                     elif "delta" in data:
                         if not first_token_received:
                             time_to_first_token = time.time() - total_start
@@ -2562,12 +2570,13 @@ async def stream_agent_loop(
     metrics = _compute_final_metrics(
         messages, full_response, total_duration, time_to_first_token,
         context_length, real_input_tokens, real_output_tokens,
-        has_real_usage, tool_events, round_texts, model=model,
+        has_real_usage, tool_events, round_texts, model=actual_model,
         last_round_input_tokens=last_round_input_tokens,
         prep_timings=prep_timings,
         backend_gen_tps=backend_gen_tps,
         backend_prefill_tps=backend_prefill_tps,
     )
+    metrics["requested_model"] = requested_model
     yield f"data: {json.dumps({'type': 'metrics', 'data': metrics})}\n\n"
 
     # Teacher-escalation: inline takeover visible in the chat stream.

src/llm_core.py

@@ -167,6 +167,9 @@ def _stream_delta_event(text: str, *, thinking: bool = False) -> str:
 def _model_activity_key(url: str, model: str) -> str:
     return f"{(url or '').strip()}|{(model or '').strip()}"
 
+def _same_model_identity(left: str, right: str) -> bool:
+    return (left or "").strip().lower() == (right or "").strip().lower()
+
 def note_model_activity(url: str, model: str):
     """Record that a real upstream request used this endpoint/model."""
     if not url or not model:
@@ -1493,6 +1496,8 @@ async def stream_llm(url: str, model: str, messages: List[Dict], temperature: fl
     _think_open_stripped = False  # opening <think> tag already removed
     _harmony_router = _HarmonyStreamRouter()
     _harmony_active = False       # sticky: gpt-oss harmony <|channel|> stream detected
+    _actual_model = ""
+    _actual_model_announced = False
 
     def _emit_tool_calls():
         """Build the tool_calls event string if any were accumulated."""
@@ -1549,6 +1554,15 @@ async def stream_llm(url: str, model: str, messages: List[Dict], temperature: fl
                         if data.strip():
                             if data.startswith("{"):
                                 j = json.loads(data)
+                                chunk_model = j.get("model")
+                                if isinstance(chunk_model, str) and chunk_model.strip():
+                                    _actual_model = chunk_model.strip()
+                                    if (
+                                        not _actual_model_announced
+                                        and not _same_model_identity(_actual_model, model)
+                                    ):
+                                        _actual_model_announced = True
+                                        yield f'data: {json.dumps({"type": "model_actual", "requested_model": model, "model": _actual_model})}\n\n'
                                 # Usage chunk (from stream_options)
                                 _choices = j.get("choices") or []
                                 _delta0 = _choices[0].get("delta") if (_choices and _choices[0] is not None) else None
@@ -1579,6 +1593,10 @@ async def stream_llm(url: str, model: str, messages: List[Dict], temperature: fl
                                             _usage_data["gen_tps"] = round(_tm["predicted_per_second"], 2)
                                         if _tm.get("prompt_per_second"):
                                             _usage_data["prefill_tps"] = round(_tm["prompt_per_second"], 2)
+                                    if _actual_model:
+                                        _usage_data["model"] = _actual_model
+                                        if not _same_model_identity(_actual_model, model):
+                                            _usage_data["requested_model"] = model
                                     yield f'data: {json.dumps({"type": "usage", "data": _usage_data})}\n\n'
                                 elif "choices" in j:
                                     _c0 = (j["choices"] or [None])[0]
@@ -1791,6 +1809,13 @@ async def stream_llm_with_fallback(candidates, messages, **kwargs):
                 continue
             # Any data chunk other than the terminal [DONE] means real output.
             if chunk.startswith("data: ") and not chunk.startswith("data: [DONE]"):
+                try:
+                    event_data = json.loads(chunk[6:])
+                except Exception:
+                    event_data = {}
+                if event_data.get("type") == "model_actual":
+                    yield chunk
+                    continue
                 # First real output from a NON-primary candidate: tell the client
                 # the selected model failed and another answered. Without this the
                 # fallback is invisible — a misconfigured provider looks like it

static/js/chat.js

@@ -53,7 +53,27 @@ import { createStreamRenderer } from './streamingRenderer.js';
 
   // shortModel and modelColor are now in chatRenderer.js
   var _shortModel = chatRenderer.shortModel;
+  var _modelRouteLabel = chatRenderer.modelRouteLabel;
+  var _sameModelName = chatRenderer.sameModelName;
   var _applyModelColor = chatRenderer.applyModelColor;
+  function _setRoleModelLabel(roleEl, requestedModel, actualModel, opts) {
+    if (!roleEl) return;
+    opts = opts || {};
+    const tsSpan = roleEl.querySelector('.role-timestamp');
+    const req = requestedModel || actualModel || '';
+    const actual = actualModel || requestedModel || '';
+    let label = _modelRouteLabel(req, actual);
+    if (opts.suffix) label += ' (' + opts.suffix + ')';
+    if (opts.characterName) label = opts.characterName;
+    roleEl.textContent = label + ' ';
+    _applyModelColor(roleEl, actual || req);
+    if (req && actual && !_sameModelName(req, actual)) {
+      roleEl.title = req + ' -> ' + actual + (opts.reason ? ': ' + opts.reason : '');
+    } else if (!opts.reason) {
+      roleEl.removeAttribute('title');
+    }
+    if (tsSpan) roleEl.appendChild(tsSpan);
+  }
   // Per-session research tracking (supports concurrent research across sessions)
   const _researchingStreamIds = new Set();
   let _researchTimerEl = null, _researchTimerInterval = null;
@@ -556,7 +576,6 @@ import { createStreamRenderer } from './streamingRenderer.js';
     let _thinkOpen = false;
     let holder = null;
     let finalMeta = null;
-    let finalModelName = null;
     let spinner = null;
     let timedOut = false;
     let processingProbeTimer = null;
@@ -892,11 +911,13 @@ import { createStreamRenderer } from './streamingRenderer.js';
         loadingText = 'Processing request...';
       }
 
-      var roleLabel = _shortModel(modelName);
+      var roleLabel = _modelRouteLabel(modelName, modelName);
       var _charNameInit = presetsModule.getCharacterName ? presetsModule.getCharacterName() : '';
       if (_charNameInit) roleLabel = _charNameInit;
       const roleTs = new Date().toLocaleTimeString([], {hour: '2-digit', minute:'2-digit'});
       holder.innerHTML = `<div class="role">${uiModule.esc(roleLabel)} <span class="role-timestamp">${roleTs}</span></div><div class="body"></div>`;
+      holder._requestedModel = modelName;
+      holder._actualModel = modelName;
       _applyModelColor(holder.querySelector('.role'), modelName);
       holder.style.position = 'relative';
       
@@ -1807,21 +1828,16 @@ import { createStreamRenderer } from './streamingRenderer.js';
                 if (!_isBg && holder) {
                   const roleEl = holder.querySelector('.role');
                   if (roleEl) {
-                    const tsSpan = roleEl.querySelector('.role-timestamp');
-                    var _modelLabel = _shortModel(json.model);
-                    if (json.suffix) {
-                      _modelLabel += ' (' + json.suffix + ')';
-                      holder._roleSuffix = json.suffix;
-                    }
+                    holder._requestedModel = json.requested_model || json.model || holder._requestedModel;
+                    holder._actualModel = json.model || holder._actualModel || holder._requestedModel;
+                    if (json.suffix) holder._roleSuffix = json.suffix;
                     // Prepend character name if sent by server or set locally
                     var _charName = json.character_name || (presetsModule.getCharacterName ? presetsModule.getCharacterName() : '');
-                    if (_charName) {
-                      _modelLabel = _charName;
-                      holder._characterName = _charName;
-                    }
-                    roleEl.textContent = _modelLabel + ' ';
-                    _applyModelColor(roleEl, json.model);
-                    if (tsSpan) roleEl.appendChild(tsSpan);
+                    if (_charName) holder._characterName = _charName;
+                    _setRoleModelLabel(roleEl, holder._requestedModel, holder._actualModel, {
+                      suffix: holder._roleSuffix,
+                      characterName: holder._characterName,
+                    });
                   }
                 }
               } else if (json.type === 'fallback') {
@@ -1841,6 +1857,14 @@ import { createStreamRenderer } from './streamingRenderer.js';
                         (json.reason ? ': ' + json.reason : '') + ' — answered by ' + (json.answered_by || '');
                       _applyModelColor(_rEl, json.answered_by);
                       if (_tsS) _rEl.appendChild(_tsS);
+                      holder._requestedModel = json.selected_model || holder._requestedModel || modelName;
+                      const _hasResolvedActual = holder._actualModel && !_sameModelName(holder._actualModel, holder._requestedModel);
+                      holder._actualModel = _hasResolvedActual ? holder._actualModel : (json.answered_by || holder._actualModel || holder._requestedModel);
+                      _setRoleModelLabel(_rEl, holder._requestedModel, holder._actualModel, {
+                        suffix: holder._roleSuffix,
+                        characterName: holder._characterName,
+                        reason: json.reason,
+                      });
                     }
                   }
                 }
@@ -1882,6 +1906,15 @@ import { createStreamRenderer } from './streamingRenderer.js';
                   _chatBox.appendChild(note);
                   try { note.scrollIntoView({ block: 'end', behavior: 'smooth' }); } catch (_) { uiModule.scrollHistory && uiModule.scrollHistory(); }
                 }
+              } else if (json.type === 'model_actual') {
+                if (!_isBg && holder) {
+                  holder._requestedModel = json.requested_model || holder._requestedModel || modelName;
+                  holder._actualModel = json.model || holder._actualModel || holder._requestedModel;
+                  _setRoleModelLabel(holder.querySelector('.role'), holder._requestedModel, holder._actualModel, {
+                    suffix: holder._roleSuffix,
+                    characterName: holder._characterName,
+                  });
+                }
               } else if (json.type === 'attachments') {
                 if (_isBg) continue;
                 // Update user bubble — replace file chips with image previews
@@ -1959,6 +1992,10 @@ import { createStreamRenderer } from './streamingRenderer.js';
                 }
               } else if (json.type === 'metrics') {
                 metrics = json.data;
+                if (!_isBg && holder && metrics) {
+                  holder._requestedModel = metrics.requested_model || holder._requestedModel || modelName;
+                  holder._actualModel = metrics.model || holder._actualModel || holder._requestedModel;
+                }
                 if (_isBg) {
                   var bgM = _backgroundStreams.get(streamSessionId);
                   if (bgM) bgM.metrics = json.data;
@@ -2441,8 +2478,10 @@ import { createStreamRenderer } from './streamingRenderer.js';
                 const newRole = document.createElement('div');
                 newRole.className = 'role';
                 const metaS = sessionModule.getSessions().find(s => s.id === streamSessionId);
-                newRole.textContent = _shortModel(metaS?.model) || '';
-                _applyModelColor(newRole, metaS?.model);
+                const _roundRequested = holder?._requestedModel || metaS?.model;
+                const _roundActual = holder?._actualModel || _roundRequested;
+                newRole.textContent = _modelRouteLabel(_roundRequested, _roundActual) || '';
+                _applyModelColor(newRole, _roundActual);
                 newWrap.appendChild(newRole);
                 const newBody = document.createElement('div');
                 newBody.className = 'body';
@@ -2548,18 +2587,16 @@ import { createStreamRenderer } from './streamingRenderer.js';
       const _isBgFinal = (sessionModule.getCurrentSessionId() !== streamSessionId) || _backgroundStreams.has(streamSessionId);
       if (!_isBgFinal) {
         finalMeta = sessionModule.getSessions().find(s => s.id === sessionModule.getCurrentSessionId());
-        finalModelName = _shortModel(metrics?.model || finalMeta?.model);
-        // Preserve suffix (e.g. "Research") if set by model_info event
-        if (holder._roleSuffix) finalModelName += ' (' + holder._roleSuffix + ')';
+        const _finalActualModel = metrics?.model || holder._actualModel || finalMeta?.model;
+        const _finalRequestedModel = metrics?.requested_model || holder._requestedModel || finalMeta?.model || _finalActualModel;
         // Prepend character name if set
         var _charNameFinal = presetsModule.getCharacterName ? presetsModule.getCharacterName() : '';
-        if (_charNameFinal) finalModelName = _charNameFinal;
         const roleEl = holder.querySelector('.role');
         if (roleEl) {
-          const tsSpan = roleEl.querySelector('.role-timestamp');
-          roleEl.textContent = finalModelName + ' ';
-          _applyModelColor(roleEl, metrics?.model || finalMeta?.model);
-          if (tsSpan) roleEl.appendChild(tsSpan);
+          _setRoleModelLabel(roleEl, _finalRequestedModel, _finalActualModel, {
+            suffix: holder._roleSuffix,
+            characterName: _charNameFinal || holder._characterName,
+          });
         }
         holder.dataset.raw = accumulated;
 

static/js/chatRenderer.js

@@ -537,6 +537,39 @@ export function shortModel(name) {
   return short;
 }
 
+function modelValue(name) {
+  if (name == null) return '';
+  return String(name).trim();
+}
+
+export function sameModelName(left, right) {
+  const a = modelValue(left);
+  const b = modelValue(right);
+  if (!a || !b) return false;
+  return a.toLowerCase() === b.toLowerCase()
+    || shortModel(a).toLowerCase() === shortModel(b).toLowerCase();
+}
+
+export function modelRouteLabel(requestedModel, actualModel) {
+  const requested = modelValue(requestedModel);
+  const actual = modelValue(actualModel) || requested;
+  if (!requested || sameModelName(requested, actual)) return shortModel(actual || requested);
+  return shortModel(requested) + ' -> ' + shortModel(actual);
+}
+
+export function replyModelPair(modelName, metadata) {
+  const meta = metadata || {};
+  const actualFromMeta = modelValue(meta.model || meta.actual_model);
+  const requestedFromMeta = modelValue(meta.requested_model || meta.selected_model);
+  if (actualFromMeta || requestedFromMeta) {
+    const actual = actualFromMeta || requestedFromMeta || modelValue(modelName);
+    const requested = requestedFromMeta || actual;
+    return { requestedModel: requested, actualModel: actual };
+  }
+  const fallback = modelValue(modelName);
+  return { requestedModel: fallback, actualModel: fallback };
+}
+
 /**
  * Generate a consistent HSL color for a model name.
  * Returns an hsl() string. The hue is derived from a string hash,
@@ -577,7 +610,11 @@ export function applyModelColor(roleEl, modelName) {
   }
   // Replace generic dot with provider logo if available
   const logo = providerLogo(modelName);
-  if (logo && !roleEl.querySelector('.role-provider-logo')) {
+  const existingLogo = roleEl.querySelector('.role-provider-logo');
+  if (!logo) {
+    if (existingLogo) existingLogo.remove();
+    roleEl.classList.remove('has-logo');
+  } else if (!existingLogo) {
     const span = document.createElement('span');
     span.className = 'role-provider-logo';
     span.innerHTML = logo;
@@ -1933,8 +1970,12 @@ export function addMessage(role, content, modelName, metadata) {
           wrap.className = 'msg msg-ai' + (r > 0 ? ' msg-continuation' : '');
           const roleEl = document.createElement('div');
           roleEl.className = 'role';
-          const contModel = modelName || metadata?.model;
-          roleEl.textContent = shortModel(contModel);
+          const pair = replyModelPair(modelName, metadata);
+          const contModel = pair.actualModel || pair.requestedModel;
+          roleEl.textContent = modelRouteLabel(pair.requestedModel, contModel);
+          if (pair.requestedModel && contModel && !sameModelName(pair.requestedModel, contModel)) {
+            roleEl.title = pair.requestedModel + ' -> ' + contModel;
+          }
           applyModelColor(roleEl, contModel);
           if (r === 0) roleEl.appendChild(roleTimestamp(metadata?.timestamp));
           wrap.appendChild(roleEl);
@@ -2057,8 +2098,9 @@ export function addMessage(role, content, modelName, metadata) {
     r.className = 'role';
     const isSlash = metadata?.source === 'slash';
     const isCompacted = metadata?.compacted;
-    const resolvedModel = modelName || metadata?.model;
-    var _roleText = role === 'user' ? 'You' : (isSlash || isCompacted) ? 'Odysseus' : shortModel(resolvedModel);
+    const replyModels = replyModelPair(modelName, metadata);
+    const resolvedModel = replyModels.actualModel || replyModels.requestedModel;
+    var _roleText = role === 'user' ? 'You' : (isSlash || isCompacted) ? 'Odysseus' : modelRouteLabel(replyModels.requestedModel, resolvedModel);
     if (role === 'assistant' && (metadata?.research || metadata?.research_clarification)) {
       _roleText += ' (Research)';
     }
@@ -2069,6 +2111,9 @@ export function addMessage(role, content, modelName, metadata) {
     }
     r.textContent = _roleText;
     if (role !== 'user') {
+      if (!isSlash && !isCompacted && replyModels.requestedModel && resolvedModel && !sameModelName(replyModels.requestedModel, resolvedModel)) {
+        r.title = replyModels.requestedModel + ' -> ' + resolvedModel;
+      }
       if (!isSlash && !isCompacted) applyModelColor(r, resolvedModel);
       r.appendChild(roleTimestamp(metadata?.timestamp));
     }
@@ -2335,6 +2380,9 @@ export function addMessage(role, content, modelName, metadata) {
 
 const chatRenderer = {
   shortModel,
+  sameModelName,
+  modelRouteLabel,
+  replyModelPair,
   modelColor,
   applyModelColor,
   getModelCost,

tests/test_chat_helpers.py

@@ -1,7 +1,12 @@
 import pytest
 from fastapi import HTTPException
 
-from routes.chat_helpers import _enforce_chat_privileges, clean_thinking_for_save, needs_auto_name
+from routes.chat_helpers import (
+    _enforce_chat_privileges,
+    clean_thinking_for_save,
+    needs_auto_name,
+    save_assistant_response,
+)
 
 
 class _AuthManager:
@@ -64,6 +69,15 @@ def test_allowed_models_nonempty_list_still_restricts_without_new_flag(monkeypat
         )
 
 
+class _FakeSession:
+    def __init__(self, model="selected-model"):
+        self.model = model
+        self.history = []
+
+    def add_message(self, message):
+        self.history.append(message)
+
+
 @pytest.mark.parametrize("name,expected", [
     # 24h format (the bug this PR fixes)
     ("deepseek-v4-flash 14:05:33", True),
@@ -130,3 +144,19 @@ def test_clean_thinking_for_save_extracts_thought_tag():
 
     assert content == "Final answer."
     assert metadata["thinking"] == "internal reasoning"
+
+
+def test_save_assistant_response_preserves_actual_and_requested_model():
+    sess = _FakeSession("selected-model")
+
+    save_assistant_response(
+        sess,
+        session_manager=None,
+        session_id="s1",
+        full_response="hello",
+        last_metrics={"model": "actual-model", "input_tokens": 1, "output_tokens": 2},
+        incognito=True,
+    )
+
+    assert sess.history[-1].metadata["requested_model"] == "selected-model"
+    assert sess.history[-1].metadata["model"] == "actual-model"

tests/test_chat_metrics.py

@@ -82,6 +82,32 @@ def _usage_event(monkeypatch, lines):
     return asyncio.run(run())
 
 
+def _stream_events(monkeypatch, lines):
+    """Drive stream_llm and return all JSON data events."""
+    monkeypatch.setattr(llm_core, "_get_http_client", lambda: _FakeClient(lines))
+    monkeypatch.setattr(llm_core, "_is_host_dead", lambda u: False)
+    monkeypatch.setattr(llm_core, "note_model_activity", lambda *a, **k: None)
+    monkeypatch.setattr(llm_core, "_clear_host_dead", lambda *a, **k: None)
+
+    async def run():
+        events = []
+        async for chunk in llm_core.stream_llm(
+            "http://127.0.0.1:8081/v1/chat/completions",
+            "openrouter/auto",
+            [{"role": "user", "content": "hi"}],
+        ):
+            for ln in chunk.split("\n"):
+                ln = ln.strip()
+                if ln.startswith("data: ") and ln[6:] != "[DONE]":
+                    try:
+                        events.append(json.loads(ln[6:]))
+                    except ValueError:
+                        pass
+        return events
+
+    return asyncio.run(run())
+
+
 # A real llama.cpp final chunk carries `usage` (delta empty / choices []) with a
 # sibling `timings` block. The decode speed here (78.91) is far above the
 # wall-clock figure the old code would have shown.
@@ -127,6 +153,31 @@ def test_stream_llm_omits_tps_when_backend_has_no_timings(monkeypatch):
     assert "prefill_tps" not in usage
 
 
+def test_stream_llm_surfaces_provider_resolved_model(monkeypatch):
+    events = _stream_events(monkeypatch, [
+        'data: ' + json.dumps({
+            "model": "meta-llama/llama-3.3-70b-instruct:free",
+            "choices": [{"index": 0, "delta": {"content": "Hi"}}],
+        }),
+        'data: ' + json.dumps({
+            "model": "meta-llama/llama-3.3-70b-instruct:free",
+            "choices": [],
+            "usage": {"prompt_tokens": 8, "completion_tokens": 5},
+        }),
+        "data: [DONE]",
+    ])
+
+    actual = [e for e in events if e.get("type") == "model_actual"]
+    assert actual == [{
+        "type": "model_actual",
+        "requested_model": "openrouter/auto",
+        "model": "meta-llama/llama-3.3-70b-instruct:free",
+    }]
+    usage = [e["data"] for e in events if e.get("type") == "usage"][0]
+    assert usage["requested_model"] == "openrouter/auto"
+    assert usage["model"] == "meta-llama/llama-3.3-70b-instruct:free"
+
+
 # --- _compute_final_metrics preference logic --------------------------------
 
 def _metrics(**overrides):