diff --git a/README.md b/README.md
index 040fee89..4a6c54b3 100644
--- a/README.md
+++ b/README.md
@@ -1299,7 +1299,7 @@ Thanks to all contributors who helped make 9Router better!
 
 Built on the shoulders of giants:
 
-- **CLIProxyAPI(https://github.com/router-for-me/CLIProxyAPI)** — original Go implementation that inspired this JavaScript port.
+- **[CLIProxyAPI](https://github.com/router-for-me/CLIProxyAPI)** — original Go implementation that inspired this JavaScript port.
 - **[RTK](https://github.com/rtk-ai/rtk)** ![Stars](https://img.shields.io/github/stars/rtk-ai/rtk?style=flat&color=yellow) — Rust token-saver. 9Router ports its compression pipeline to JS → **−20-40% input tokens** on every request.
 - **[Caveman](https://github.com/JuliusBrussee/caveman)** ![Stars](https://img.shields.io/github/stars/JuliusBrussee/caveman?style=flat&color=yellow) by **[@JuliusBrussee](https://github.com/JuliusBrussee)** — viral *"why use many token when few token do trick"*. 9Router adapts its prompt → **−65% output tokens**.
 
diff --git a/open-sse/config/runtimeConfig.js b/open-sse/config/runtimeConfig.js
index a82cff3a..c2a4888e 100644
--- a/open-sse/config/runtimeConfig.js
+++ b/open-sse/config/runtimeConfig.js
@@ -32,7 +32,10 @@ export const MEMORY_CONFIG = {
 };
 
 // Stream stall timeout: abort if no chunk received within this duration
-export const STREAM_STALL_TIMEOUT_MS = 3 * 60 * 1000;
+export const STREAM_STALL_TIMEOUT_MS = 60 * 1000;
+
+// Fetch connect timeout: abort if upstream doesn't return response headers within this duration
+export const FETCH_CONNECT_TIMEOUT_MS = 30 * 1000;
 
 // Default token limits
 export const DEFAULT_MAX_TOKENS = 64000;
diff --git a/open-sse/executors/base.js b/open-sse/executors/base.js
index 8cb46721..adb942b1 100644
--- a/open-sse/executors/base.js
+++ b/open-sse/executors/base.js
@@ -1,5 +1,6 @@
-import { HTTP_STATUS, RETRY_CONFIG, DEFAULT_RETRY_CONFIG, resolveRetryEntry } from "../config/runtimeConfig.js";
+import { HTTP_STATUS, RETRY_CONFIG, DEFAULT_RETRY_CONFIG, resolveRetryEntry, FETCH_CONNECT_TIMEOUT_MS } from "../config/runtimeConfig.js";
 import { proxyAwareFetch } from "../utils/proxyFetch.js";
+import { dbg } from "../utils/debugLog.js";
 
 /**
  * BaseExecutor - Base class for provider executors
@@ -121,13 +122,25 @@ export class BaseExecutor {
 
       if (!retryAttemptsByUrl[urlIndex]) retryAttemptsByUrl[urlIndex] = 0;
 
+      // Abort if upstream doesn't return response headers within FETCH_CONNECT_TIMEOUT_MS
+      const connectCtrl = new AbortController();
+      const connectTimer = setTimeout(() => connectCtrl.abort(new Error("fetch connect timeout")), FETCH_CONNECT_TIMEOUT_MS);
+      const mergedSignal = signal ? AbortSignal.any([signal, connectCtrl.signal]) : connectCtrl.signal;
+
       try {
+        const bodyStr = JSON.stringify(transformedBody);
+        const fetchT0 = Date.now();
+        dbg("FETCH", `${this.provider.toUpperCase()} → ${url} | body=${bodyStr.length}B | connectTimeout=${FETCH_CONNECT_TIMEOUT_MS}ms`);
         const response = await proxyAwareFetch(url, {
           method: "POST",
           headers,
-          body: JSON.stringify(transformedBody),
-          signal
+          body: bodyStr,
+          signal: mergedSignal
         }, proxyOptions);
+        clearTimeout(connectTimer);
+        const ct = response.headers?.get?.("content-type") || "";
+        const cl = response.headers?.get?.("content-length") || "?";
+        dbg("FETCH", `${this.provider.toUpperCase()} ← ${response.status} | ttft=${Date.now() - fetchT0}ms | ct=${ct} | cl=${cl}`);
 
         if (await tryRetry(urlIndex, response.status, `status ${response.status}`)) { urlIndex--; continue; }
 
@@ -139,8 +152,12 @@ export class BaseExecutor {
 
         return { response, url, headers, transformedBody };
       } catch (error) {
+        clearTimeout(connectTimer);
         lastError = error;
-        if (error.name === "AbortError") throw error;
+        const isConnectTimeout = connectCtrl.signal.aborted && error.name === "AbortError";
+        dbg("FETCH", `${this.provider.toUpperCase()} ✖ ${error.name}: ${error.message}${isConnectTimeout ? " (connect timeout)" : ""}`);
+        // Connect timeout is internal — convert to retryable network error, don't propagate AbortError
+        if (error.name === "AbortError" && !isConnectTimeout) throw error;
 
         // Map network/fetch exceptions to 502 retry config
         if (await tryRetry(urlIndex, HTTP_STATUS.BAD_GATEWAY, `network "${error.message}"`)) { urlIndex--; continue; }
diff --git a/open-sse/executors/codex.js b/open-sse/executors/codex.js
index 80cbd6d3..eaac4bf6 100644
--- a/open-sse/executors/codex.js
+++ b/open-sse/executors/codex.js
@@ -6,11 +6,100 @@ import { normalizeResponsesInput } from "../translator/helpers/responsesApiHelpe
 import { fetchImageAsBase64 } from "../translator/helpers/imageHelper.js";
 import { getModelUpstreamId } from "../config/providerModels.js";
 import { getConsistentMachineId } from "../../src/shared/utils/machineId.js";
+import { DEFAULT_RETRY_CONFIG, resolveRetryEntry } from "../config/runtimeConfig.js";
+import { dbg } from "../utils/debugLog.js";
+
+// SSE error patterns inside 200-OK body that should trigger retry as if 503
+const CODEX_SSE_OVERLOADED_PATTERNS = ["server_is_overloaded", "service_unavailable_error"];
+const CODEX_SSE_PEEK_BYTES = 4096;
 
 // In-memory map: hash(machineId + first assistant content) → { sessionId, lastUsed }
 const SESSION_TTL_MS = 60 * 60 * 1000; // 1 hour
 const assistantSessionMap = new Map();
 
+// Server-generated item id prefixes that Codex /responses cannot resolve when store=false
+const SERVER_ID_PATTERN = /^(rs|fc|resp|msg)_/;
+
+// Hosted tool types that Codex/OpenAI Responses executes server-side
+const CODEX_HOSTED_TOOL_TYPES = new Set([
+  "image_generation", "web_search", "web_search_preview", "file_search",
+  "computer", "computer_use_preview", "code_interpreter", "mcp", "local_shell"
+]);
+
+// Allowlist of fields accepted by Codex Responses API — anything else is stripped
+const RESPONSES_API_ALLOWLIST = new Set([
+  "model", "input", "instructions", "tools", "tool_choice", "stream", "store",
+  "reasoning", "service_tier", "include", "prompt_cache_key", "client_metadata"
+]);
+
+// Convert role=system → role=developer in body.input (keeps content in cacheable prefix)
+function convertSystemToDeveloperRole(body) {
+  if (!Array.isArray(body.input)) return;
+  for (const item of body.input) {
+    if (!item || typeof item !== "object" || Array.isArray(item)) continue;
+    const isSystemMsg = item.role === "system" && (!item.type || item.type === "message");
+    if (isSystemMsg) item.role = "developer";
+  }
+}
+
+// Strip server-generated item IDs (rs_/fc_/resp_/msg_) from input — avoids 404 with store=false
+function stripStoredItemReferences(body) {
+  if (!Array.isArray(body.input)) return;
+  body.input = body.input.filter((item) => {
+    if (typeof item === "string" && SERVER_ID_PATTERN.test(item)) return false;
+    if (item && typeof item === "object" && !Array.isArray(item)) {
+      if (item.type === "item_reference") return false;
+      if (typeof item.id === "string" && SERVER_ID_PATTERN.test(item.id)) delete item.id;
+    }
+    return true;
+  });
+}
+
+// Flatten Chat-Completions tool shape into Responses flat format + filter unsupported tools
+function normalizeCodexTools(body) {
+  if (!Array.isArray(body.tools)) return;
+  const validNames = new Set();
+  body.tools = body.tools.filter((tool) => {
+    if (!tool || typeof tool !== "object" || Array.isArray(tool)) return false;
+    const type = typeof tool.type === "string" ? tool.type : "";
+    if (type === "namespace") {
+      if (Array.isArray(tool.tools)) {
+        for (const st of tool.tools) {
+          const n = typeof st?.name === "string" ? st.name.trim().slice(0, 128) : "";
+          if (n) validNames.add(n);
+        }
+      }
+      return true;
+    }
+    if (type !== "function") {
+      if (!type || tool.function || typeof tool.name === "string") return false;
+      return CODEX_HOSTED_TOOL_TYPES.has(type);
+    }
+    const fn = tool.function && typeof tool.function === "object" && !Array.isArray(tool.function) ? tool.function : null;
+    const rawName = typeof tool.name === "string" ? tool.name : (typeof fn?.name === "string" ? fn.name : "");
+    const name = rawName.trim();
+    if (!name) return false;
+    const description = typeof tool.description === "string" ? tool.description : (typeof fn?.description === "string" ? fn.description : "");
+    const parameters = (tool.parameters && typeof tool.parameters === "object" && !Array.isArray(tool.parameters))
+      ? tool.parameters
+      : (fn?.parameters && typeof fn.parameters === "object" && !Array.isArray(fn.parameters) ? fn.parameters : { type: "object", properties: {} });
+    for (const k of Object.keys(tool)) delete tool[k];
+    tool.type = "function";
+    tool.name = name.slice(0, 128);
+    if (description) tool.description = description;
+    tool.parameters = parameters;
+    validNames.add(name);
+    return true;
+  });
+  // Drop tool_choice if it references an unknown function name
+  if (body.tool_choice && typeof body.tool_choice === "object" && !Array.isArray(body.tool_choice)) {
+    if (body.tool_choice.type === "function") {
+      const n = typeof body.tool_choice.name === "string" ? body.tool_choice.name.trim() : "";
+      if (!n || !validNames.has(n)) delete body.tool_choice;
+    }
+  }
+}
+
 // Cache machine ID at module level (resolved once)
 let cachedMachineId = null;
 getConsistentMachineId().then(id => { cachedMachineId = id; });
@@ -33,32 +122,54 @@ function extractItemText(item) {
   return "";
 }
 
-// Resolve session_id from first assistant message + machineId to avoid cross-user collision
-function resolveConversationSessionId(input, machineId) {
-  const machineSessionId = machineId ? `sess_${hashContent(machineId)}` : generateSessionId();
-  if (!Array.isArray(input) || input.length === 0) return machineSessionId;
+// Normalize a session id candidate (trim, length cap)
+function normalizeSessionId(value) {
+  if (typeof value !== "string") return null;
+  const v = value.trim();
+  if (!v || v.length > 256) return null;
+  return v;
+}
 
-  // Find first assistant message that has actual text content
-  let text = "";
-  for (const item of input) {
-    if (item.role === "assistant") {
-      text = extractItemText(item);
-      if (text) break;
+// Resolve prompt-cache session id with priority: body → assistant-text-hash → workspaceId → machineId
+function resolveCacheSessionId(body, credentials, machineId) {
+  // 1. Client-provided session/conversation id (highest priority — stable per conversation)
+  const fromBody =
+    normalizeSessionId(body?.prompt_cache_key) ||
+    normalizeSessionId(body?.session_id) ||
+    normalizeSessionId(body?.conversation_id);
+  if (fromBody) return fromBody;
+
+  // 2. Hash accumulated assistant text (≥50 chars) — sticky session across turns
+  if (Array.isArray(body?.input) && body.input.length > 0) {
+    let text = "";
+    const MIN_LEN = 50;
+    const CAP_LEN = 200;
+    for (const item of body.input) {
+      if (item?.role !== "assistant") continue;
+      const t = extractItemText(item);
+      if (!t) continue;
+      text += t;
+      if (text.length >= CAP_LEN) break;
+    }
+    if (text.length >= MIN_LEN) {
+      const hash = hashContent((machineId || "") + text.slice(0, CAP_LEN));
+      const entry = assistantSessionMap.get(hash);
+      if (entry) {
+        entry.lastUsed = Date.now();
+        return entry.sessionId;
+      }
+      const sessionId = generateSessionId();
+      assistantSessionMap.set(hash, { sessionId, lastUsed: Date.now() });
+      return sessionId;
     }
   }
-  if (!text) return machineSessionId;
 
-  const hash = hashContent((machineId || "") + text);
-  const entry = assistantSessionMap.get(hash);
-  if (entry) {
-    entry.lastUsed = Date.now();
-    return entry.sessionId;
-  }
+  // 3. Account-wide fallback (workspaceId from connection)
+  const workspaceId = normalizeSessionId(credentials?.providerSpecificData?.workspaceId);
+  if (workspaceId) return workspaceId;
 
-
-  const sessionId = generateSessionId();
-  assistantSessionMap.set(hash, { sessionId, lastUsed: Date.now() });
-  return sessionId;
+  // 4. Last resort — stable per-machine id
+  return machineId ? `sess_${hashContent(machineId)}` : generateSessionId();
 }
 
 // Cleanup expired entries periodically
@@ -80,12 +191,19 @@ export class CodexExecutor extends BaseExecutor {
   }
 
   /**
-   * Override headers to add session_id per conversation
-   * transformRequest runs BEFORE buildHeaders, sets this._currentSessionId
+   * Override headers to add codex-specific identity headers.
+   * transformRequest runs BEFORE buildHeaders, sets this._currentSessionId.
    */
   buildHeaders(credentials, stream = true) {
     const headers = super.buildHeaders(credentials, stream);
     headers["session_id"] = this._currentSessionId || credentials?.connectionId || "default";
+    // Identify client type to Codex backend (matches official codex CLI)
+    if (!headers["originator"]) headers["originator"] = "codex_cli_rs";
+    // Workspace binding header — improves account scope + cache affinity
+    const workspaceId = credentials?.providerSpecificData?.workspaceId;
+    if (typeof workspaceId === "string" && workspaceId && !headers["chatgpt-account-id"]) {
+      headers["chatgpt-account-id"] = workspaceId;
+    }
     return headers;
   }
 
@@ -117,9 +235,100 @@ export class CodexExecutor extends BaseExecutor {
   }
 
   async execute(args) {
-    // Fetch remote images before the synchronous transform/execute pipeline
-    await this.prefetchImages(args.body);
-    return super.execute(args);
+    const imgCount = Array.isArray(args.body?.input) ? args.body.input.reduce((n, it) => n + (Array.isArray(it.content) ? it.content.filter(c => c.type === "image_url").length : 0), 0) : 0;
+    const inputLen = Array.isArray(args.body?.input) ? args.body.input.length : 0;
+    dbg("CODEX", `execute start | inputItems=${inputLen} | images=${imgCount} | sessionId=${this._currentSessionId || "pending"}`);
+    if (imgCount > 0) {
+      const t0 = Date.now();
+      await this.prefetchImages(args.body);
+      dbg("CODEX", `prefetchImages done | ${Date.now() - t0}ms`);
+    } else {
+      await this.prefetchImages(args.body);
+    }
+
+    // Retry loop for SSE-level overloaded errors (200 OK body contains event: error)
+    // Reuses 503 retry config — same semantic: upstream temporarily unavailable
+    const retryConfig = { ...DEFAULT_RETRY_CONFIG, ...this.config.retry };
+    const { attempts, delayMs } = resolveRetryEntry(retryConfig[503]);
+    let attempt = 0;
+    while (true) {
+      const result = await super.execute(args);
+      const peek = await this._peekSseOverloaded(result.response);
+      if (!peek.matched) {
+        // Replace body with re-assembled stream (prefix bytes already read + rest)
+        if (peek.replacementBody) {
+          result.response = new Response(peek.replacementBody, {
+            status: result.response.status,
+            statusText: result.response.statusText,
+            headers: result.response.headers,
+          });
+        }
+        return result;
+      }
+      if (attempt >= attempts) {
+        args.log?.warn?.("RETRY", `CODEX | SSE overloaded "${peek.matched}" — retries exhausted (${attempt}/${attempts})`);
+        // Out of retries → return with replacement body so client gets the error
+        if (peek.replacementBody) {
+          result.response = new Response(peek.replacementBody, {
+            status: result.response.status,
+            statusText: result.response.statusText,
+            headers: result.response.headers,
+          });
+        }
+        return result;
+      }
+      attempt++;
+      args.log?.debug?.("RETRY", `CODEX | SSE "${peek.matched}" retry ${attempt}/${attempts} after ${delayMs / 1000}s`);
+      dbg("CODEX", `SSE overloaded "${peek.matched}" → retry ${attempt}/${attempts} in ${delayMs}ms`);
+      try { await result.response.body?.cancel?.(); } catch { /* noop */ }
+      await new Promise(r => setTimeout(r, delayMs));
+    }
+  }
+
+  // Peek first N bytes of SSE body to detect upstream "overloaded" errors.
+  // Returns { matched: string|null, replacementBody: ReadableStream|null }.
+  // Caller MUST use replacementBody (original body has been read).
+  async _peekSseOverloaded(response) {
+    if (!response || !response.ok || !response.body) return { matched: null, replacementBody: null };
+    const reader = response.body.getReader();
+    const decoder = new TextDecoder();
+    const chunks = [];
+    let text = "";
+    let matched = null;
+    try {
+      while (text.length < CODEX_SSE_PEEK_BYTES) {
+        const { done, value } = await reader.read();
+        if (done) break;
+        chunks.push(value);
+        text += decoder.decode(value, { stream: true });
+        const hit = CODEX_SSE_OVERLOADED_PATTERNS.find(p => text.includes(p));
+        if (hit) { matched = hit; break; }
+      }
+    } catch (e) {
+      dbg("CODEX", `peek read error: ${e.message}`);
+    }
+    reader.releaseLock();
+
+    // Re-assemble stream: prefix chunks + remaining upstream body
+    const upstream = response.body;
+    let upstreamReader = null;
+    const replacementBody = new ReadableStream({
+      start(controller) {
+        for (const c of chunks) controller.enqueue(c);
+        upstreamReader = upstream.getReader();
+      },
+      async pull(controller) {
+        try {
+          const { done, value } = await upstreamReader.read();
+          if (done) { controller.close(); return; }
+          controller.enqueue(value);
+        } catch (e) { controller.error(e); }
+      },
+      cancel(reason) {
+        try { upstreamReader?.cancel(reason); } catch { /* noop */ }
+      },
+    });
+    return { matched, replacementBody };
   }
 
   // Parse Codex usage_limit_reached to extract precise resetsAtMs; fallback to default otherwise
@@ -154,8 +363,8 @@ export class CodexExecutor extends BaseExecutor {
   transformRequest(model, body, stream, credentials) {
     this._isCompact = !!body._compact;
     delete body._compact;
-    // Resolve conversation-stable session_id from input history + machineId
-    this._currentSessionId = resolveConversationSessionId(body.input, cachedMachineId);
+    // Resolve conversation-stable session_id (priority: body → assistant-text → workspace → machine)
+    this._currentSessionId = resolveCacheSessionId(body, credentials, cachedMachineId);
     // Convert string input to array format (Codex API requires input as array)
     const normalized = normalizeResponsesInput(body.input);
     if (normalized) body.input = normalized;
@@ -165,6 +374,13 @@ export class CodexExecutor extends BaseExecutor {
       body.input = [{ type: "message", role: "user", content: [{ type: "input_text", text: "..." }] }];
     }
 
+    // Keep system prompts in body.input as role=developer so they stay in the cacheable prefix
+    convertSystemToDeveloperRole(body);
+    // Strip server-generated item IDs (rs_/fc_/resp_/msg_) — Codex /responses can't resolve when store=false
+    stripStoredItemReferences(body);
+    // Flatten function tools + drop unsupported types
+    normalizeCodexTools(body);
+
     // Ensure streaming is enabled (Codex API requires it)
     body.stream = true;
 
@@ -176,6 +392,11 @@ export class CodexExecutor extends BaseExecutor {
     // Ensure store is false (Codex requirement)
     body.store = false;
 
+    // Inject prompt_cache_key for stable Codex prompt caching
+    if (!body.prompt_cache_key && this._currentSessionId) {
+      body.prompt_cache_key = this._currentSessionId;
+    }
+
     // Map virtual Codex review models to the upstream Codex model before suffix parsing.
     body.model = getModelUpstreamId("cx", body.model || model);
 
@@ -223,6 +444,12 @@ export class CodexExecutor extends BaseExecutor {
     delete body.metadata; // Cursor sends this but Codex doesn't support it
     delete body.stream_options; // Cursor sends this but Codex doesn't support it
     delete body.safety_identifier; // Droid CLI sends this but Codex doesn't support it
+    delete body.previous_response_id; // store=false → backend can't resolve previous resp; avoid 404
+
+    // Final allowlist filter — strip any unknown field that could trigger upstream "routing_unsupported"
+    for (const k of Object.keys(body)) {
+      if (!RESPONSES_API_ALLOWLIST.has(k)) delete body[k];
+    }
 
     return body;
   }
diff --git a/open-sse/translator/response/openai-responses.js b/open-sse/translator/response/openai-responses.js
index 184b5396..0cf79cbd 100644
--- a/open-sse/translator/response/openai-responses.js
+++ b/open-sse/translator/response/openai-responses.js
@@ -568,10 +568,17 @@ export function openaiResponsesToOpenAIResponse(chunk, state) {
     return null;
   }
 
-  // Reasoning events (convert to content or skip)
+  // Reasoning summary delta → emit as reasoning_content for client thinking display
   if (eventType === "response.reasoning_summary_text.delta") {
-    // Optionally include reasoning as content, or skip
-    return null;
+    const delta = data.delta || "";
+    if (!delta) return null;
+    return {
+      id: state.chatId,
+      object: "chat.completion.chunk",
+      created: state.created,
+      model: state.model || "unknown",
+      choices: [{ index: 0, delta: { reasoning_content: delta }, finish_reason: null }]
+    };
   }
 
   // Ignore other events
diff --git a/open-sse/utils/debugLog.js b/open-sse/utils/debugLog.js
new file mode 100644
index 00000000..67cdc31f
--- /dev/null
+++ b/open-sse/utils/debugLog.js
@@ -0,0 +1,14 @@
+// Debug logging utility — only active in dev mode (NODE_ENV !== "production")
+// Outputs are tagged with [DBG:tag] for easy grep/filter
+const isDev = process.env.NODE_ENV !== "production";
+
+function ts() {
+  return new Date().toLocaleTimeString("en-US", { hour12: false, hour: "2-digit", minute: "2-digit", second: "2-digit" });
+}
+
+export function dbg(tag, msg) {
+  if (!isDev) return;
+  console.log(`[${ts()}] 🐛 [DBG:${tag}] ${msg}`);
+}
+
+export const isDebugEnabled = isDev;
diff --git a/open-sse/utils/proxyFetch.js b/open-sse/utils/proxyFetch.js
index 43b71642..16cac731 100644
--- a/open-sse/utils/proxyFetch.js
+++ b/open-sse/utils/proxyFetch.js
@@ -1,9 +1,101 @@
 import { Readable } from "stream";
 import { MEMORY_CONFIG } from "../config/runtimeConfig.js";
+import { dbg } from "./debugLog.js";
 
 const originalFetch = globalThis.fetch;
 const proxyDispatchers = new Map();
 
+// ─── TLS fingerprinting via got-scraping (browser-like JA3) ───────────────
+// Lazy-loaded once; if import fails (missing optional native deps in some
+// envs) we silently fall back to native fetch — no behavioral change.
+let _gotScraping = null;
+let _gotScrapingChecked = false;
+const _gotScrapingLoggedHosts = new Set();
+
+async function getGotScraping() {
+  if (_gotScrapingChecked) return _gotScraping;
+  _gotScrapingChecked = true;
+  try {
+    const mod = await import("got-scraping");
+    _gotScraping = typeof mod.gotScraping === "function" ? mod.gotScraping : null;
+    if (_gotScraping) dbg("TLS", "got-scraping loaded (browser-like JA3 enabled)");
+  } catch (e) {
+    console.warn(`[ProxyFetch] got-scraping unavailable, falling back to native fetch: ${e.message}`);
+    _gotScraping = null;
+  }
+  return _gotScraping;
+}
+
+// Run a request through got-scraping streaming, return a fetch-compatible Response
+async function gotScrapingFetch(url, options) {
+  const gs = await getGotScraping();
+  if (!gs) return null;
+
+  const method = (options.method || "GET").toUpperCase();
+  const headersInit = options.headers || {};
+  const headers = headersInit instanceof Headers
+    ? Object.fromEntries(headersInit.entries())
+    : { ...headersInit };
+
+  return new Promise((resolve, reject) => {
+    let settled = false;
+    const stream = gs.stream({
+      url,
+      method,
+      headers,
+      body: method === "GET" || method === "HEAD" ? undefined : options.body,
+      throwHttpErrors: false,
+      retry: { limit: 0 },
+      timeout: { request: undefined }, // streaming → no overall timeout
+      followRedirect: false,
+      decompress: true,
+    });
+
+    if (options.signal) {
+      const onAbort = () => { try { stream.destroy(new Error("aborted")); } catch { /* noop */ } };
+      if (options.signal.aborted) onAbort();
+      else options.signal.addEventListener("abort", onAbort, { once: true });
+    }
+
+    stream.once("response", (res) => {
+      if (settled) return;
+      settled = true;
+      const resHeaders = new Headers();
+      for (const [k, v] of Object.entries(res.headers || {})) {
+        if (Array.isArray(v)) v.forEach((x) => resHeaders.append(k, String(x)));
+        else if (v != null) resHeaders.set(k, String(v));
+      }
+      const body = Readable.toWeb(stream);
+      resolve(new Response(body, { status: res.statusCode, statusText: res.statusMessage || "", headers: resHeaders }));
+    });
+
+    stream.once("error", (err) => {
+      if (settled) return;
+      settled = true;
+      reject(err);
+    });
+  });
+}
+
+async function tryGotScrapingFetch(url, options) {
+  try {
+    const res = await gotScrapingFetch(url, options);
+    if (res) {
+      try {
+        const host = new URL(typeof url === "string" ? url : url.toString()).hostname;
+        if (!_gotScrapingLoggedHosts.has(host)) {
+          _gotScrapingLoggedHosts.add(host);
+          dbg("TLS", `using got-scraping for ${host}`);
+        }
+      } catch { /* noop */ }
+    }
+    return res;
+  } catch (e) {
+    console.warn(`[ProxyFetch] got-scraping request failed, fallback to native fetch: ${e.message}`);
+    return null;
+  }
+}
+
 // DNS cache — use Map to avoid prototype pollution via malformed hostnames
 const DNS_CACHE = new Map();
 const MITM_BYPASS_HOSTS = [
@@ -255,6 +347,8 @@ export async function proxyAwareFetch(url, options = {}, proxyOptions = null) {
     }
   }
 
+  // got-scraping disabled — use native fetch directly
+  // (Re-enable per-host by wrapping with tryGotScrapingFetch when needed)
   return originalFetch(url, options);
 }
 
diff --git a/open-sse/utils/stream.js b/open-sse/utils/stream.js
index 138f2ee3..42829686 100644
--- a/open-sse/utils/stream.js
+++ b/open-sse/utils/stream.js
@@ -3,6 +3,7 @@ import { FORMATS } from "../translator/formats.js";
 import { trackPendingRequest, appendRequestLog } from "@/lib/usageDb.js";
 import { extractUsage, hasValidUsage, estimateUsage, logUsage, addBufferToUsage, filterUsageForFormat, COLORS } from "./usageTracking.js";
 import { parseSSELine, hasValuableContent, fixInvalidId, formatSSE } from "./streamHelpers.js";
+import { dbg, isDebugEnabled } from "./debugLog.js";
 
 export { COLORS, formatSSE };
 
@@ -58,11 +59,15 @@ export function createSSEStream(options = {}) {
   let accumulatedContent = "";
   let accumulatedThinking = "";
   let ttftAt = null;
+  let sseLineCount = 0;
+  let sseEmittedCount = 0;
+  const eventTypeCounts = {};
 
   return new TransformStream({
     transform(chunk, controller) {
       if (!ttftAt) {
         ttftAt = Date.now();
+        dbg("SSE", `${provider}/${model} | first chunk received | size=${chunk?.byteLength || 0}B`);
       }
       const text = decoder.decode(chunk, { stream: true });
       buffer += text;
@@ -73,6 +78,14 @@ export function createSSEStream(options = {}) {
 
       for (const line of lines) {
         const trimmed = line.trim();
+        if (isDebugEnabled && trimmed) {
+          sseLineCount++;
+          if (trimmed.startsWith("event:")) {
+            const evt = trimmed.slice(6).trim();
+            eventTypeCounts[evt] = (eventTypeCounts[evt] || 0) + 1;
+            if (eventTypeCounts[evt] <= 2) dbg("SSE", `recv event: ${evt} (#${eventTypeCounts[evt]})`);
+          }
+        }
 
         // Passthrough mode: normalize and forward
         if (mode === STREAM_MODE.PASSTHROUGH) {
@@ -248,12 +261,15 @@ export function createSSEStream(options = {}) {
             const output = formatSSE(item, sourceFormat);
             reqLogger?.appendConvertedChunk?.(output);
             controller.enqueue(sharedEncoder.encode(output));
+            sseEmittedCount++;
           }
         }
       }
     },
 
     flush(controller) {
+      const evtSummary = Object.entries(eventTypeCounts).map(([k, v]) => `${k}=${v}`).join(",") || "none";
+      dbg("SSE", `flush | provider=${provider} | model=${model} | recvLines=${sseLineCount} | emitted=${sseEmittedCount} | events=[${evtSummary}]`);
       trackPendingRequest(model, provider, connectionId, false);
       try {
         const remaining = decoder.decode();
diff --git a/open-sse/utils/streamHandler.js b/open-sse/utils/streamHandler.js
index f3fc50c8..567b59ac 100644
--- a/open-sse/utils/streamHandler.js
+++ b/open-sse/utils/streamHandler.js
@@ -1,5 +1,6 @@
 // Stream handler with disconnect detection - shared for all providers
 import { STREAM_STALL_TIMEOUT_MS } from "../config/runtimeConfig.js";
+import { dbg, isDebugEnabled } from "./debugLog.js";
 
 // Get HH:MM:SS timestamp
 function getTimeString() {
@@ -38,6 +39,7 @@ export function createStreamController({ onDisconnect, onError, log, provider, m
       disconnected = true;
 
       logStream(`disconnect: ${reason}`);
+      dbg("CTRL", `${provider}/${model} | disconnect=${reason} | dur=${Date.now() - startTime}ms`);
 
       // Delay abort to allow cleanup
       abortTimeout = setTimeout(() => {
@@ -117,8 +119,23 @@ export function createDisconnectAwareStream(transformStream, streamController) {
         streamController.handleError(error);
         reader.cancel().catch(() => {});
         writer.abort().catch(() => {});
-        
-        if (!wasConnected || error.name === "AbortError" || error.message?.includes("aborted")) {
+
+        // Treat network resets / socket hang up / abort as graceful close
+        const msg = error?.message || "";
+        const code = error?.code || error?.cause?.code || "";
+        const isNetworkClose =
+          error.name === "AbortError" ||
+          msg.includes("aborted") ||
+          msg.includes("socket hang up") ||
+          msg.includes("ECONNRESET") ||
+          msg.includes("ETIMEDOUT") ||
+          msg.includes("EPIPE") ||
+          code === "ECONNRESET" ||
+          code === "ETIMEDOUT" ||
+          code === "EPIPE" ||
+          code === "UND_ERR_SOCKET";
+
+        if (!wasConnected || isNetworkClose) {
           try {
             controller.close();
           } catch (e) {
@@ -158,6 +175,11 @@ export function createDisconnectAwareStream(transformStream, streamController) {
  */
 export function pipeWithDisconnect(providerResponse, transformStream, streamController) {
   let stallTimer = null;
+  let chunkCount = 0;
+  let totalBytes = 0;
+  let lastChunkAt = Date.now();
+  const t0 = Date.now();
+  const tag = "STREAM";
   const clearStall = () => {
     if (stallTimer) { clearTimeout(stallTimer); stallTimer = null; }
   };
@@ -165,6 +187,7 @@ export function pipeWithDisconnect(providerResponse, transformStream, streamCont
     clearStall();
     stallTimer = setTimeout(() => {
       stallTimer = null;
+      dbg(tag, `STALL TIMEOUT ${STREAM_STALL_TIMEOUT_MS}ms | chunks=${chunkCount} | bytes=${totalBytes} | sinceLast=${Date.now() - lastChunkAt}ms`);
       streamController.handleError?.(new Error("stream stall timeout"));
       streamController.abort?.();
     }, STREAM_STALL_TIMEOUT_MS);
@@ -177,20 +200,30 @@ export function pipeWithDisconnect(providerResponse, transformStream, streamCont
     signal: streamController.signal,
     startTime: streamController.startTime,
     isConnected: () => streamController.isConnected(),
-    handleComplete: () => { clearStall(); streamController.handleComplete(); },
-    handleError: (e) => { clearStall(); streamController.handleError(e); },
-    handleDisconnect: (r) => { clearStall(); streamController.handleDisconnect(r); },
+    handleComplete: () => { dbg(tag, `complete | chunks=${chunkCount} | bytes=${totalBytes} | dur=${Date.now() - t0}ms`); clearStall(); streamController.handleComplete(); },
+    handleError: (e) => { dbg(tag, `error: ${e?.message} | chunks=${chunkCount} | bytes=${totalBytes} | dur=${Date.now() - t0}ms`); clearStall(); streamController.handleError(e); },
+    handleDisconnect: (r) => { dbg(tag, `disconnect: ${r} | chunks=${chunkCount} | bytes=${totalBytes} | dur=${Date.now() - t0}ms`); clearStall(); streamController.handleDisconnect(r); },
     abort: () => { clearStall(); streamController.abort(); }
   };
 
   armStall();
+  dbg(tag, `pipe start | stallTimeout=${STREAM_STALL_TIMEOUT_MS}ms`);
 
   const upstreamTap = new TransformStream({
     transform(chunk, controller) {
+      chunkCount++;
+      const sz = chunk?.byteLength || chunk?.length || 0;
+      totalBytes += sz;
+      const now = Date.now();
+      const gap = now - lastChunkAt;
+      lastChunkAt = now;
+      if (isDebugEnabled && (chunkCount <= 5 || chunkCount % 20 === 0 || gap > 5000)) {
+        dbg(tag, `chunk #${chunkCount} | size=${sz}B | gap=${gap}ms | total=${totalBytes}B`);
+      }
       armStall();
       controller.enqueue(chunk);
     },
-    flush() { clearStall(); }
+    flush() { dbg(tag, `upstream EOF | chunks=${chunkCount} | bytes=${totalBytes} | dur=${Date.now() - t0}ms`); clearStall(); }
   });
 
   const transformedBody = providerResponse.body
diff --git a/package.json b/package.json
index 340622f1..c15d0f89 100644
--- a/package.json
+++ b/package.json
@@ -22,6 +22,7 @@
     "confbox": "^0.2.4",
     "express": "^5.2.1",
     "fs": "^0.0.1-security",
+    "got-scraping": "^4.2.1",
     "http-proxy-middleware": "^3.0.5",
     "jose": "^6.1.3",
     "marked": "^18.0.1",
diff --git a/src/mitm/antigravityIdeVersion.js b/src/mitm/antigravityIdeVersion.js
new file mode 100644
index 00000000..cac9bc47
--- /dev/null
+++ b/src/mitm/antigravityIdeVersion.js
@@ -0,0 +1,58 @@
+"use strict";
+
+// Rewrite Antigravity IDE markers so upstream AG 2.x backend accepts the request.
+// User-Agent header (antigravity/<old>) and body.metadata.ideVersion are forced
+// to a known-good IDE version. Hardcoded MVP — toggle/version configurable later.
+
+const ANTIGRAVITY_IDE_VERSION = "1.23.2";
+const ANTIGRAVITY_IDE_VERSION_OVERRIDE_ENABLED = true;
+
+function shouldRewriteMetadata(metadata) {
+  if (!metadata || typeof metadata !== "object" || Array.isArray(metadata)) return false;
+  if (String(metadata.ideName || "").toLowerCase() === "antigravity") return true;
+  if (String(metadata.ideType || "").toUpperCase() === "ANTIGRAVITY") return true;
+  return Object.prototype.hasOwnProperty.call(metadata, "ideVersion");
+}
+
+function rewriteAntigravityUserAgent(userAgent, version) {
+  if (typeof userAgent !== "string" || !userAgent.includes("antigravity/")) return userAgent;
+  return userAgent.replace(/antigravity\/[^\s]+/, `antigravity/${version}`);
+}
+
+function applyAntigravityIdeVersionOverride(bodyBuffer, headers, log = () => {}) {
+  if (!ANTIGRAVITY_IDE_VERSION_OVERRIDE_ENABLED) {
+    return { bodyBuffer, headers, applied: false, version: ANTIGRAVITY_IDE_VERSION };
+  }
+
+  const nextHeaders = { ...headers };
+  const nextUserAgent = rewriteAntigravityUserAgent(nextHeaders["user-agent"], ANTIGRAVITY_IDE_VERSION);
+  const userAgentChanged = nextUserAgent !== nextHeaders["user-agent"];
+  if (userAgentChanged) nextHeaders["user-agent"] = nextUserAgent;
+
+  try {
+    const parsed = JSON.parse(bodyBuffer.toString());
+    if (!shouldRewriteMetadata(parsed?.metadata)) {
+      if (userAgentChanged) log(`🛰️ [antigravity] user-agent version override → ${ANTIGRAVITY_IDE_VERSION}`);
+      return { bodyBuffer, headers: nextHeaders, applied: userAgentChanged, version: ANTIGRAVITY_IDE_VERSION };
+    }
+
+    const previousVersion = parsed.metadata.ideVersion;
+    parsed.metadata.ideVersion = ANTIGRAVITY_IDE_VERSION;
+    const nextBodyBuffer = Buffer.from(JSON.stringify(parsed));
+    log(`🛰️ [antigravity] IDE version override: ${previousVersion || "unknown"} → ${ANTIGRAVITY_IDE_VERSION}`);
+    return { bodyBuffer: nextBodyBuffer, headers: nextHeaders, applied: true, version: ANTIGRAVITY_IDE_VERSION };
+  } catch (e) {
+    if (userAgentChanged) {
+      log(`🛰️ [antigravity] user-agent version override → ${ANTIGRAVITY_IDE_VERSION}`);
+      return { bodyBuffer, headers: nextHeaders, applied: true, version: ANTIGRAVITY_IDE_VERSION };
+    }
+    log(`🛰️ [antigravity] IDE version override skipped: ${e.message}`);
+    return { bodyBuffer, headers: nextHeaders, applied: false, version: ANTIGRAVITY_IDE_VERSION };
+  }
+}
+
+module.exports = {
+  ANTIGRAVITY_IDE_VERSION,
+  applyAntigravityIdeVersionOverride,
+  rewriteAntigravityUserAgent,
+};
diff --git a/src/mitm/config.js b/src/mitm/config.js
index 3c14adba..eb8aefc9 100644
--- a/src/mitm/config.js
+++ b/src/mitm/config.js
@@ -31,7 +31,7 @@ const URL_PATTERNS = {
 // Synonym map: rawModel from request → canonical alias key in mitmAlias DB
 const MODEL_SYNONYMS = {
   antigravity: {
-    "gemini-default": "gemini-3-flash-agent",
+    "gemini-default": "gemini-3.5-flash-low",
     "gemini-3.1-pro-high": "gemini-pro-agent",
     "gemini-3-pro-high": "gemini-pro-agent",
     "gemini-3-pro-low": "gemini-3.1-pro-low",
diff --git a/src/mitm/server.js b/src/mitm/server.js
index f334db60..09469ad0 100644
--- a/src/mitm/server.js
+++ b/src/mitm/server.js
@@ -1,4 +1,6 @@
 const https = require("https");
+const http2 = require("http2");
+const tls = require("tls");
 const fs = require("fs");
 const path = require("path");
 const dns = require("dns");
@@ -9,6 +11,7 @@ const { IS_DEV, LSOF_BIN, TARGET_HOSTS, URL_PATTERNS, MODEL_SYNONYMS, MODEL_PATT
 const { DATA_DIR, MITM_DIR } = require("./paths");
 const { getCertForDomain } = require("./cert/generate");
 const { getMitmAlias } = require("./dbReader");
+const { applyAntigravityIdeVersionOverride } = require("./antigravityIdeVersion");
 const LOCAL_PORT = 443;
 const IS_WIN = process.platform === "win32";
 const ENABLE_FILE_LOG = IS_DEV;
@@ -129,16 +132,136 @@ function getMappedModel(tool, model) {
  */
 async function passthrough(req, res, bodyBuffer, onResponse) {
   const originalHost = (req.headers.host || TARGET_HOSTS[0]).split(":")[0];
-  const targetHost = HOST_REWRITE[originalHost] || originalHost;
-  const targetIP = await resolveTargetIP(targetHost);
+  // Only rewrite host for chat endpoints — daily-cloudcode-pa rejects auth/login requests
+  const isChatEndpoint = req.url.includes(":generateContent") || req.url.includes(":streamGenerateContent");
+  const targetHost = isChatEndpoint ? (HOST_REWRITE[originalHost] || originalHost) : originalHost;
   const dumper = ENABLE_FILE_LOG ? createResponseDumper(req, "passthrough") : null;
 
+  const tool = getToolForHost(req.headers.host);
+  const versionOverride = tool === "antigravity"
+    ? applyAntigravityIdeVersionOverride(bodyBuffer, req.headers, log)
+    : { bodyBuffer, headers: req.headers };
+  const bodyForForwarding = versionOverride.bodyBuffer;
+  const headersForForwarding = { ...versionOverride.headers, host: targetHost };
+  if (bodyForForwarding !== bodyBuffer) {
+    headersForForwarding["content-length"] = String(bodyForForwarding.length);
+  }
+
+  // ALPN negotiate: try HTTP/2 first (like browsers/mitmweb), fallback HTTP/1.1
+  try {
+    const proto = await negotiateAlpn(targetHost);
+    if (proto === "h2") {
+      return await passthroughHttp2(req, res, bodyForForwarding, headersForForwarding, targetHost, onResponse, dumper);
+    }
+  } catch (e) {
+    err(`[mitm] ALPN negotiate failed: ${e.message}, fallback to HTTP/1.1`);
+  }
+
+  return passthroughHttps(req, res, bodyForForwarding, headersForForwarding, targetHost, onResponse, dumper);
+}
+
+// ── ALPN negotiation cache ────────────────────────────────────
+const alpnCache = new Map(); // host → "h2" | "http/1.1"
+async function negotiateAlpn(host) {
+  if (alpnCache.has(host)) return alpnCache.get(host);
+  const ip = await resolveTargetIP(host);
+  return new Promise((resolve, reject) => {
+    const socket = tls.connect({
+      host: ip, port: 443, servername: host,
+      ALPNProtocols: ["h2", "http/1.1"], rejectUnauthorized: false,
+    }, () => {
+      const proto = socket.alpnProtocol || "http/1.1";
+      alpnCache.set(host, proto);
+      log(`🔗 [mitm] ALPN ${host} → ${proto}`);
+      socket.end();
+      resolve(proto);
+    });
+    socket.once("error", reject);
+    socket.setTimeout(5000, () => { socket.destroy(new Error("ALPN timeout")); });
+  });
+}
+
+// HTTP/2 passthrough using node:http2 native
+async function passthroughHttp2(req, res, bodyBuffer, headers, targetHost, onResponse, dumper) {
+  const targetIP = await resolveTargetIP(targetHost);
+  // HTTP/2 pseudo-headers required; strip HTTP/1.1-only headers
+  const h2Headers = {};
+  for (const [k, v] of Object.entries(headers)) {
+    const lk = k.toLowerCase();
+    if (lk === "host" || lk === "connection" || lk === "keep-alive" ||
+        lk === "transfer-encoding" || lk === "upgrade" || lk === "proxy-connection") continue;
+    h2Headers[lk] = v;
+  }
+  h2Headers[":method"] = req.method;
+  h2Headers[":path"] = req.url;
+  h2Headers[":scheme"] = "https";
+  h2Headers[":authority"] = targetHost;
+
+  return new Promise((resolve) => {
+    const client = http2.connect(`https://${targetHost}`, {
+      createConnection: () => tls.connect({
+        host: targetIP, port: 443, servername: targetHost,
+        ALPNProtocols: ["h2"], rejectUnauthorized: false,
+      }),
+    });
+    client.once("error", (e) => {
+      err(`[mitm] http2 client error: ${e.message}`);
+      if (dumper) { dumper.writeChunk(`\n[ERROR h2] ${e.message}\n`); dumper.end(); }
+      if (!res.headersSent) res.writeHead(502);
+      if (!res.writableEnded) res.end("Bad Gateway");
+      try { client.close(); } catch {}
+      resolve();
+    });
+
+    const stream = client.request(h2Headers, { endStream: bodyBuffer.length === 0 });
+    if (bodyBuffer.length > 0) stream.end(bodyBuffer);
+
+    stream.once("response", (responseHeaders) => {
+      const status = responseHeaders[":status"];
+      // Filter pseudo-headers + connection-specific
+      const outHeaders = {};
+      for (const [k, v] of Object.entries(responseHeaders)) {
+        if (k.startsWith(":")) continue;
+        if (k === "connection" || k === "keep-alive" || k === "transfer-encoding") continue;
+        outHeaders[k] = v;
+      }
+      res.writeHead(status, outHeaders);
+      if (dumper) dumper.writeHeader(status, outHeaders);
+
+      const chunks = [];
+      stream.on("data", chunk => {
+        if (dumper) dumper.writeChunk(chunk);
+        if (onResponse) chunks.push(chunk);
+        res.write(chunk);
+      });
+      stream.on("end", () => {
+        if (dumper) dumper.end();
+        if (!res.writableEnded) res.end();
+        if (onResponse) try { onResponse(Buffer.concat(chunks), outHeaders); } catch {}
+        try { client.close(); } catch {}
+        resolve();
+      });
+    });
+    stream.once("error", (e) => {
+      err(`[mitm] http2 stream error: ${e.message}`);
+      if (dumper) { dumper.writeChunk(`\n[ERROR h2-stream] ${e.message}\n`); dumper.end(); }
+      if (!res.headersSent) res.writeHead(502);
+      if (!res.writableEnded) res.end();
+      try { client.close(); } catch {}
+      resolve();
+    });
+  });
+}
+
+// Fallback: raw https.request HTTP/1.1 with custom DNS (bypasses /etc/hosts MITM loop)
+async function passthroughHttps(req, res, bodyBuffer, headers, targetHost, onResponse, dumper) {
+  const targetIP = await resolveTargetIP(targetHost);
   const forwardReq = https.request({
     hostname: targetIP,
     port: 443,
     path: req.url,
     method: req.method,
-    headers: { ...req.headers, host: targetHost },
+    headers,
     servername: targetHost,
     rejectUnauthorized: false
   }, (forwardRes) => {
@@ -150,7 +273,6 @@ async function passthrough(req, res, bodyBuffer, onResponse) {
       return;
     }
 
-    // Tee: forward to client AND optionally buffer + dump
     const chunks = [];
     forwardRes.on("data", chunk => {
       if (dumper) dumper.writeChunk(chunk);
diff --git a/src/shared/constants/cliTools.js b/src/shared/constants/cliTools.js
index 8f97b8bb..c3aa010c 100644
--- a/src/shared/constants/cliTools.js
+++ b/src/shared/constants/cliTools.js
@@ -8,12 +8,13 @@ export const MITM_TOOLS = {
     description: "Google Antigravity IDE with MITM",
     configType: "mitm",
     mitmDomain: "daily-cloudcode-pa.googleapis.com",
-    modelAliases: ["gemini-3-flash-agent", "gemini-3.5-flash-low", "gemini-pro-agent", "gemini-3.1-pro-low", "claude-sonnet-4-6", "claude-opus-4-6-thinking", "gpt-oss-120b-medium", "gemini-3-flash"],
+    modelAliases: ["gemini-3.5-flash-low", "gemini-3-flash-agent", "gemini-3.5-flash-extra-low", "gemini-3.1-pro-low", "gemini-pro-agent", "claude-sonnet-4-6", "claude-opus-4-6-thinking", "gpt-oss-120b-medium", "gemini-3-flash"],
     defaultModels: [
-      { id: "gemini-3-flash-agent", name: "Gemini 3.5 Flash (High) / Default", alias: "gemini-3-flash-agent" },
-      { id: "gemini-3.5-flash-low", name: "Gemini 3.5 Flash (Medium)", alias: "gemini-3.5-flash-low" },
-      { id: "gemini-pro-agent", name: "Gemini 3.1 Pro (High)", alias: "gemini-pro-agent" },
+      { id: "gemini-3.5-flash-low", name: "Gemini 3.5 Flash (Medium) / Default", alias: "gemini-3.5-flash-low" },
+      { id: "gemini-3-flash-agent", name: "Gemini 3.5 Flash (High)", alias: "gemini-3-flash-agent" },
+      { id: "gemini-3.5-flash-extra-low", name: "Gemini 3.5 Flash (Low)", alias: "gemini-3.5-flash-extra-low" },
       { id: "gemini-3.1-pro-low", name: "Gemini 3.1 Pro (Low)", alias: "gemini-3.1-pro-low" },
+      { id: "gemini-pro-agent", name: "Gemini 3.1 Pro (High)", alias: "gemini-pro-agent" },
       { id: "claude-sonnet-4-6", name: "Claude Sonnet 4.6 (Thinking)", alias: "claude-sonnet-4-6" },
       { id: "claude-opus-4-6-thinking", name: "Claude Opus 4.6 (Thinking)", alias: "claude-opus-4-6-thinking" },
       { id: "gpt-oss-120b-medium", name: "GPT-OSS 120B (Medium)", alias: "gpt-oss-120b-medium" },