diff --git a/CHANGELOG.md b/CHANGELOG.md
index c7d81b44325..8bb278fb8cf 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -30,6 +30,7 @@ _In development — bullets added per PR; finalized at release._
 - **fix(pricing): align Claude Code (`cc`) pricing with current Anthropic per-MTok rates** — the `cc` provider block in the default pricing table had stale numbers across every Claude 4.x family entry — most visibly, `claude-opus-4-5-20251101` was billed at the deprecated Opus 4.1 rate (`input $15` / `output $75`), and `claude-haiku-4-5-20251001` was at half the current Haiku 4.5 rate. The `cached` (cache hit) and `cache_creation` (5-minute cache write) multipliers were also off across Opus 4.6/4.7/4.8, Sonnet 4.5/4.6, Haiku 4.5, and Fable 5. All eight entries now match the rates Anthropic publishes (input, 5m cache write at 1.25x input, cache hit at 0.1x input, output; reasoning billed at the output rate), so cost accounting on the dashboard and per-request usage events stop under- or over-reporting Claude Code spend. (thanks @chulanpro5)
 - **fix(executors): sanitize Anthropic-shape content parts before GitHub Copilot `/chat/completions`** — Claude models on GitHub Copilot driven from clients like Cursor IDE (e.g. `gh/claude-sonnet-4.6`) failed with `Provider returned error: type has to be either 'image_url' or 'text' (reset after 30s)` because the client passed through Anthropic-shape content parts (`tool_use`, `tool_result`, `thinking`) untouched, and the Copilot chat-completions endpoint only accepts `text`/`image_url`. `GithubExecutor.transformRequest` now serializes any unsupported part type as `text` (preserving the model's context), drops empty parts, and collapses to `null` when an assistant message's only content was tool_calls — `tool_calls` ride alongside untouched. Codex-family models still route through `/responses` unchanged. (thanks @cngznNN)
 - **fix(sse):** refactor stall detection to reduce false positives on slow but progressing streams. (thanks @zakirkun)
+- **fix(providers): restore specialty validator dispatch for web-cookie providers** — the generic `/models` web-cookie probe introduced in #4023 silently took precedence over the per-provider specialty validators (qwen-web, grok-web, chatgpt-web, claude-web, gemini-web, copilot-web, deepseek-web, perplexity-web, blackbox-web, muse-spark-web, t3-web, adapta-web, inner-ai). For qwen-web this regressed the body-check fix from #3958 — the generic probe accepted any 200 as valid, where the specialty validator inspects `data.user` on `/api/v2/user` to detect expired sessions that still return 200. Every other specialty web-cookie validator was equally bypassed. The dispatcher now gates the generic probe on a `WEB_COOKIE_PROVIDERS_WITH_SPECIALTY_VALIDATOR` set so providers with bespoke validators reach them again. A new `tests/unit/web-cookie-specialty-dispatch.test.ts` enforces the invariant (every override must really be a registered web-cookie provider, and qwen-web's specialty path must hit `/api/v2/user`, not `/models`).
 
 ---
 
diff --git a/config/quality/file-size-baseline.json b/config/quality/file-size-baseline.json
index 67940a6f6e4..9e2642e11ef 100644
--- a/config/quality/file-size-baseline.json
+++ b/config/quality/file-size-baseline.json
@@ -86,12 +86,15 @@
   "_rebaseline_2026_06_20_1449_1444_test_route": "Re-baseline providers test route.ts 842->887: combined growth of sibling fixes #1449 (bound OAuth connection-test probe with a timeout) + #1444 (label a deactivated account distinctly from a revoked token), both at the same connection-test chokepoint. Cohesive route handler; not extractable without hiding the test flow.",
   "_rebaseline_2026_06_20_1409_1294_models": "Re-baseline src/lib/db/models.ts 1184->1221: combined growth of sibling fixes #1409 (cascade-delete orphaned model aliases when a provider is removed) + #1294 (persist max_input_tokens/max_output_tokens on custom models), both adding CRUD at the existing models domain module. Cohesive db module; not extractable.",
   "_rebaseline_2026_06_20_4389_thinking_toolchoice": "Re-baseline base.ts 1387->1399 (#4389): tool_choice-forced thinking guard at the existing Claude wire-image injection chokepoint (effThinking gate avoids the Anthropic 400 when tool_choice forces a tool). Cohesive guard; structural shrink tracked in #3501.",
+  "_rebaseline_2026_06_20_qwen_web_specialty_dispatch": "Re-baseline validation.ts 4518->4556 (+38) — restore-green dispatch fix for web-cookie providers regressed by #4023. The generic web-cookie /models probe added in #4023 silently took precedence over the per-provider specialty validators (qwen-web/grok-web/chatgpt-web/...), regressing the qwen-web body-check fix from #3958 and the equivalent guards for the other 12 specialty web-cookie providers. Fix gates the generic probe on a Set of providers that have a specialty validator below (WEB_COOKIE_PROVIDERS_WITH_SPECIALTY_VALIDATOR), plus a single test-export const used by the invariant test (tests/unit/web-cookie-specialty-dispatch.test.ts). Cohesive guard at the validateProviderApiKey dispatch chokepoint; not extractable without splitting the dispatcher. Structural shrink for validation.ts tracked in #3501.",
+  "_rebaseline_2026_06_20_4440_cc_pricing": "Re-baseline pricing.ts 1620->1623 (+3) — drift from PR #4440 (align Claude Code pricing with Anthropic) which was merged with --admin while file-size was already over. Pure pricing data rows; not extractable.",
+  "_rebaseline_2026_06_20_4443_reasoning_effort": "Re-baseline base.ts 1399->1407 (+8) — drift from PR #4443 (granular reasoning_effort handling for Claude models on Copilot) which was merged with --admin while file-size was already over. Cohesive per-model preserve at the existing serialization chokepoint; not extractable. Structural shrink tracked in #3501.",
   "cap": 800,
   "frozen": {
     "open-sse/translator/request/openai-to-kiro.ts": 807,
     "open-sse/config/providerRegistry.ts": 4731,
     "open-sse/executors/antigravity.ts": 1687,
-    "open-sse/executors/base.ts": 1399,
+    "open-sse/executors/base.ts": 1407,
     "open-sse/executors/chatgpt-web.ts": 2870,
     "open-sse/executors/claude-web.ts": 1057,
     "open-sse/executors/codex.ts": 1449,
@@ -175,7 +178,7 @@
     "src/lib/evals/evalRunner.ts": 961,
     "src/lib/memory/retrieval.ts": 1171,
     "src/lib/modelsDevSync.ts": 934,
-    "src/lib/providers/validation.ts": 4518,
+    "src/lib/providers/validation.ts": 4556,
     "src/lib/tailscaleTunnel.ts": 1202,
     "src/lib/usage/callLogs.ts": 975,
     "src/lib/usage/providerLimits.ts": 949,
@@ -184,7 +187,7 @@
     "src/shared/components/RequestLoggerV2.tsx": 1287,
     "src/shared/components/analytics/charts.tsx": 1558,
     "src/shared/constants/cliTools.ts": 875,
-    "src/shared/constants/pricing.ts": 1620,
+    "src/shared/constants/pricing.ts": 1623,
     "src/shared/constants/providers.ts": 3242,
     "src/shared/constants/sidebarVisibility.ts": 1100,
     "src/shared/services/cliRuntime.ts": 1090,
diff --git a/src/lib/providers/validation.ts b/src/lib/providers/validation.ts
index c6904d715cc..1c367207fd8 100644
--- a/src/lib/providers/validation.ts
+++ b/src/lib/providers/validation.ts
@@ -3992,6 +3992,33 @@ export async function validateWebCookieProvider({
   }
 }
 
+// Web-cookie providers that ship a per-provider specialty validator below
+// (registered in SPECIALTY_VALIDATORS inside validateProviderApiKey). They
+// must NOT fall into the generic /models web-cookie probe, which would
+// regress per-provider body-check guards (see #3958 for qwen-web).
+//
+// Keep this set in sync with the SPECIALTY_VALIDATORS keys that are also in
+// WEB_COOKIE_PROVIDERS — the test in
+// `tests/unit/web-cookie-specialty-dispatch.test.ts` enforces the invariant.
+const WEB_COOKIE_PROVIDERS_WITH_SPECIALTY_VALIDATOR = new Set<string>([
+  "adapta-web",
+  "blackbox-web",
+  "chatgpt-web",
+  "claude-web",
+  "copilot-web",
+  "deepseek-web",
+  "gemini-web",
+  "grok-web",
+  "inner-ai",
+  "muse-spark-web",
+  "perplexity-web",
+  "qwen-web",
+  "t3-web",
+]);
+
+export const __testing__WEB_COOKIE_PROVIDERS_WITH_SPECIALTY_VALIDATOR =
+  WEB_COOKIE_PROVIDERS_WITH_SPECIALTY_VALIDATOR;
+
 export async function validateProviderApiKey({ provider, apiKey, providerSpecificData = {} }: any) {
   const requiresApiKey = !providerAllowsOptionalApiKey(provider);
   const isLocal = isLocalProvider(provider);
@@ -4000,8 +4027,19 @@ export async function validateProviderApiKey({ provider, apiKey, providerSpecifi
     return { valid: false, error: "Provider and API key required", unsupported: false };
   }
 
-  // Web-cookie providers (session-based authentication)
-  if (WEB_COOKIE_PROVIDERS[provider]) {
+  // Web-cookie providers (session-based authentication).
+  //
+  // Skip the generic /models probe when the provider has its own specialty
+  // validator below (in SPECIALTY_VALIDATORS) — the specialty validator hits
+  // the provider's real session endpoint (e.g. qwen-web → /api/v2/user) and
+  // inspects the body for a real user/session marker, which the generic probe
+  // cannot do. Without this guard, the generic dispatch silently returns
+  // `valid:true` on any 200 (regressing the qwen-web body-check fix from #3958
+  // and the equivalent guards for the other web-cookie providers).
+  if (
+    WEB_COOKIE_PROVIDERS[provider] &&
+    !WEB_COOKIE_PROVIDERS_WITH_SPECIALTY_VALIDATOR.has(provider)
+  ) {
     try {
       return await validateWebCookieProvider({ provider, apiKey, providerSpecificData });
     } catch (error: any) {
diff --git a/tests/unit/web-cookie-specialty-dispatch.test.ts b/tests/unit/web-cookie-specialty-dispatch.test.ts
new file mode 100644
index 00000000000..a81c039c44b
--- /dev/null
+++ b/tests/unit/web-cookie-specialty-dispatch.test.ts
@@ -0,0 +1,64 @@
+// Regression guard for the dispatch order in validateProviderApiKey:
+// PR #4023 added a generic web-cookie /models probe that silently took
+// precedence over per-provider specialty validators, regressing the qwen-web
+// body-check fix from #3958 (and the equivalent guards for every other
+// specialty web-cookie provider). The fix gates the generic probe on a Set
+// of providers that have a specialty validator. This test enforces the
+// invariant: every key in that Set must really be served by the specialty
+// dispatch, never the generic probe.
+//
+// Drift mode (e.g. someone adds a new specialty web-cookie validator):
+//  → the new key must also be added to
+//    WEB_COOKIE_PROVIDERS_WITH_SPECIALTY_VALIDATOR — this test will fail
+//    until it is, surfacing the regression at PR review time.
+
+import test from "node:test";
+import assert from "node:assert/strict";
+
+import {
+  __testing__WEB_COOKIE_PROVIDERS_WITH_SPECIALTY_VALIDATOR as SPECIALTY_OVERRIDES,
+  validateProviderApiKey,
+} from "../../src/lib/providers/validation.ts";
+import { WEB_COOKIE_PROVIDERS } from "../../src/shared/constants/providers.ts";
+
+const originalFetch = globalThis.fetch;
+
+test.afterEach(() => {
+  globalThis.fetch = originalFetch;
+});
+
+test("every override is actually a registered web-cookie provider", () => {
+  for (const provider of SPECIALTY_OVERRIDES) {
+    assert.ok(
+      Object.hasOwn(WEB_COOKIE_PROVIDERS, provider),
+      `override "${provider}" is not in WEB_COOKIE_PROVIDERS — drop it or fix the typo`
+    );
+  }
+});
+
+test("a specialty web-cookie provider does NOT fall into the generic /models probe", async () => {
+  // The generic probe hits "<baseUrl>/models" and accepts any non-401/403 as
+  // valid. For qwen-web specifically the specialty validator hits
+  // /api/v2/user and inspects the body for a real `user` object. We assert
+  // the fetch URL: if dispatch lands on the generic probe, the path ends in
+  // /models; the specialty path ends in /api/v2/user.
+  const seenUrls: string[] = [];
+  globalThis.fetch = (async (url: any) => {
+    seenUrls.push(String(url));
+    return new Response("{}", {
+      status: 200,
+      headers: { "content-type": "application/json" },
+    });
+  }) as typeof fetch;
+
+  await validateProviderApiKey({ provider: "qwen-web", apiKey: "qwen-token-abc" });
+
+  assert.ok(
+    seenUrls.some((u) => u.endsWith("/api/v2/user")),
+    `expected specialty validator to call /api/v2/user, got: ${seenUrls.join(", ")}`
+  );
+  assert.ok(
+    !seenUrls.some((u) => u.endsWith("/models")),
+    `specialty dispatch leaked into the generic /models probe: ${seenUrls.join(", ")}`
+  );
+});