fix(models): normalize GLM-5.2 provider context (#6091)

Hosted GLM-5.2 provider aliases now respect their declared context caps instead of inheriting the native 1M; native/bare + verified OpenCode/ZenMux routes stay at 1M. Regression guards added.

Co-authored-by: diegosouzapw <diegosouza.pw@gmail.com>

CHANGELOG.md

@@ -22,6 +22,8 @@
 
 ### 🔧 Bug Fixes
 
+- **models (GLM-5.2 context normalization):** stop treating every hosted GLM-5.2 provider alias as the native 1M-context model. Native/bare GLM-5.2 and verified OpenCode / ZenMux routes keep their 1,000,000-token context, while hosted-provider aliases now respect the caps declared in their provider metadata instead of inheriting the native max. Regression guards: `tests/unit/model-capabilities-registry.test.ts`, `tests/unit/models-catalog-route.test.ts`. ([#6091](https://github.com/diegosouzapw/OmniRoute/pull/6091) — thanks @Thinkscape)
+
 - **providers (Gemini Web):** refresh the Gemini Web cookie handling and model catalog so live Gemini Web sessions keep authenticating and routing to current models. Regression guard: `tests/unit/gemini-web.test.ts`. ([#6095](https://github.com/diegosouzapw/OmniRoute/pull/6095) — thanks @backryun)
 
 - **providers (Perplexity Web):** refresh the Perplexity Web model catalog to the current set (GPT-5.4/5.5, Claude Sonnet 5.0 / Opus 4.8, GLM-5.2, Kimi K2.6, Nemotron 3 Ultra) and update the internal mode / `model_preference` mappings and thinking variants so requests resolve to live upstream models. Regression guard: `tests/unit/perplexity-web.test.ts`. ([#6106](https://github.com/diegosouzapw/OmniRoute/pull/6106) — thanks @backryun)

src/lib/modelCapabilities.ts

@@ -3,7 +3,13 @@ import {
   PROVIDER_MODELS,
 } from "@omniroute/open-sse/config/providerModels.ts";
 import { parseModel, resolveCanonicalProviderModel } from "@omniroute/open-sse/services/model.ts";
-import { MODEL_SPECS, getModelSpec, type ModelSpec } from "@/shared/constants/modelSpecs";
+import {
+  MODEL_SPECS,
+  getAuthoritativeContextWindow,
+  getAuthoritativeProviderContextWindow,
+  getModelSpec,
+  type ModelSpec,
+} from "@/shared/constants/modelSpecs";
 import { getSyncedCapability } from "@/lib/modelsDevSync";
 import { getModelContextOverride } from "@/lib/db/modelContextOverrides";
 import { isVisionModelId } from "@/shared/constants/visionModels";
@@ -178,6 +184,22 @@ function getStaticSpec(modelId: string | null, rawModel: string | null): ModelSp
   return undefined;
 }
 
+function getAuthoritativeStaticContextWindow(
+  provider: string | null,
+  modelId: string | null,
+  rawModel: string | null
+): number | null {
+  for (const candidate of [modelId, rawModel]) {
+    const providerContextWindow = getAuthoritativeProviderContextWindow(provider, candidate);
+    if (typeof providerContextWindow === "number") return providerContextWindow;
+  }
+  for (const candidate of [modelId, rawModel]) {
+    const contextWindow = getAuthoritativeContextWindow(candidate);
+    if (typeof contextWindow === "number") return contextWindow;
+  }
+  return null;
+}
+
 function getStaticSpecCanonicalModelId(modelId: string | null, rawModel: string | null) {
   const candidates = [modelId, rawModel].filter(
     (candidate): candidate is string => typeof candidate === "string" && candidate.length > 0
@@ -351,7 +373,13 @@ export function getResolvedModelCapabilities(input: CapabilityInput): ResolvedMo
         : null) ??
       (typeof spec?.supportsThinking === "boolean" ? spec.supportsThinking : null));
 
+  const authoritativeContextWindow = getAuthoritativeStaticContextWindow(
+    resolved.provider,
+    resolved.model,
+    resolved.rawModel
+  );
   const contextWindow =
+    authoritativeContextWindow ??
     synced?.limit_context ??
     (typeof registryModel?.contextLength === "number" ? registryModel.contextLength : null) ??
     spec?.contextWindow ??
@@ -378,7 +406,7 @@ export function getResolvedModelCapabilities(input: CapabilityInput): ResolvedMo
     structuredOutput: synced?.structured_output ?? null,
     temperature: synced?.temperature ?? null,
     contextWindow,
-    maxInputTokens: synced?.limit_input ?? contextWindow,
+    maxInputTokens: authoritativeContextWindow ?? synced?.limit_input ?? contextWindow,
     maxOutputTokens:
       synced?.limit_output ??
       (typeof registryModel?.maxOutputTokens === "number" ? registryModel.maxOutputTokens : null) ??

src/lib/modelMetadataRegistry.ts

@@ -4,6 +4,8 @@ import { getModelInfo } from "@/sse/services/model";
 import { getModelAliases } from "@/lib/db/models";
 import { getResolvedModelCapabilities } from "@/lib/modelCapabilities";
 import {
+  getAuthoritativeContextWindow,
+  getAuthoritativeProviderContextWindow,
   getModelSpec,
   resolveModelAlias as resolveStaticModelAlias,
 } from "@/shared/constants/modelSpecs";
@@ -273,6 +275,11 @@ export function enrichCatalogModelEntry<T extends JsonRecord>(
 
   const nextEntry: JsonRecord = { ...entry };
   const existingName = asNonEmptyString(entry.name);
+  const authoritativeContextWindow =
+    getAuthoritativeProviderContextWindow(metadata.provider, metadata.model) ??
+    getAuthoritativeProviderContextWindow(provider, model) ??
+    getAuthoritativeContextWindow(metadata.model) ??
+    getAuthoritativeContextWindow(model);
   const capabilityFields = {
     ...(typeof metadata.capabilities.vision === "boolean"
       ? { vision: metadata.capabilities.vision }
@@ -309,7 +316,7 @@ export function enrichCatalogModelEntry<T extends JsonRecord>(
   }
 
   if (
-    typeof nextEntry.context_length !== "number" &&
+    (typeof nextEntry.context_length !== "number" || authoritativeContextWindow !== null) &&
     typeof metadata.limits.contextWindow === "number"
   ) {
     nextEntry.context_length = metadata.limits.contextWindow;
@@ -319,7 +326,10 @@ export function enrichCatalogModelEntry<T extends JsonRecord>(
     nextEntry.max_output_tokens = metadata.limits.maxOutputTokens;
   }
 
-  if (typeof metadata.limits.maxInputTokens === "number") {
+  if (
+    typeof metadata.limits.maxInputTokens === "number" &&
+    (typeof nextEntry.max_input_tokens !== "number" || authoritativeContextWindow !== null)
+  ) {
     nextEntry.max_input_tokens = metadata.limits.maxInputTokens;
   }
 

src/shared/constants/modelSpecs.ts

@@ -48,6 +48,23 @@ const BEDROCK_CLAUDE_ALIASES = (...modelIds: string[]) => [
   ),
 ];
 
+// Provider discovery/sync sources can under-report GLM-5.2 IDs as 128K.
+// Keep native/bare Z.AI GLM-5.2 context authoritative, but do not blindly apply
+// it to every provider-wrapped alias: hosted providers can and do cap lower.
+const AUTHORITATIVE_CONTEXT_WINDOW_MODEL_IDS = new Set(["glm-5.2", "glm-5.2-high", "glm-5.2-max"]);
+const AUTHORITATIVE_PROVIDER_CONTEXT_WINDOWS = new Map<string, number>([
+  ["cloudflare-ai/@cf/zai-org/glm-5.2", 262144],
+  // Hugging Face Router has 1M-capable backends, but bare routing can select
+  // lower-context providers (notably Together at 262K), so advertise a safe floor
+  // unless the caller can pin a 1M-capable backend.
+  ["huggingface/zai-org/glm-5.2", 262144],
+  ["opencode/glm-5.2", 1000000],
+  ["opencode-zen/glm-5.2", 1000000],
+  ["opencode-go/glm-5.2", 1000000],
+  ["zenmux/z-ai/glm-5.2", 1000000],
+  ["zenmux/z-ai/glm-5.2-free", 1000000],
+]);
+
 export const MODEL_SPECS: Record<string, ModelSpec> = {
   "gpt-5.5": {
     maxOutputTokens: 128000,
@@ -476,29 +493,53 @@ export const MODEL_SPECS: Record<string, ModelSpec> = {
   __default__: {},
 };
 
-export function getModelSpec(modelId: string): ModelSpec | undefined {
-  if (MODEL_SPECS[modelId]) return MODEL_SPECS[modelId];
+export function getCanonicalModelSpecId(modelId: string): string | null {
+  if (MODEL_SPECS[modelId]) return modelId;
 
   // Case-insensitive lookups: upstream model ids are often capitalized
   // (e.g. "MiniMax-M2.7") while specs/aliases use lowercase ids (#3141).
   const lower = modelId.toLowerCase();
 
   // Exact match (case-insensitive)
-  for (const [canonical, spec] of Object.entries(MODEL_SPECS)) {
-    if (canonical.toLowerCase() === lower) return spec;
+  for (const canonical of Object.keys(MODEL_SPECS)) {
+    if (canonical.toLowerCase() === lower) return canonical;
   }
 
   // Buscas por alias (case-insensitive)
-  for (const [, spec] of Object.entries(MODEL_SPECS)) {
-    if (spec.aliases?.some((alias) => alias.toLowerCase() === lower)) return spec;
+  for (const [canonical, spec] of Object.entries(MODEL_SPECS)) {
+    if (spec.aliases?.some((alias) => alias.toLowerCase() === lower)) return canonical;
   }
 
   // Prefix matching (case-insensitive)
-  for (const [key, spec] of Object.entries(MODEL_SPECS)) {
-    if (key !== "__default__" && lower.startsWith(key.toLowerCase())) return spec;
+  for (const key of Object.keys(MODEL_SPECS)) {
+    if (key !== "__default__" && lower.startsWith(key.toLowerCase())) return key;
   }
 
-  return undefined;
+  return null;
+}
+
+export function getModelSpec(modelId: string): ModelSpec | undefined {
+  const canonical = getCanonicalModelSpecId(modelId);
+  return canonical ? MODEL_SPECS[canonical] : undefined;
+}
+
+export function getAuthoritativeContextWindow(modelId: string | null | undefined): number | null {
+  if (typeof modelId !== "string" || modelId.length === 0) return null;
+  const normalized = modelId.toLowerCase();
+  for (const canonical of AUTHORITATIVE_CONTEXT_WINDOW_MODEL_IDS) {
+    if (canonical.toLowerCase() === normalized)
+      return MODEL_SPECS[canonical]?.contextWindow ?? null;
+  }
+  return null;
+}
+
+export function getAuthoritativeProviderContextWindow(
+  provider: string | null | undefined,
+  modelId: string | null | undefined
+): number | null {
+  if (typeof provider !== "string" || typeof modelId !== "string") return null;
+  const key = `${provider}/${modelId}`.toLowerCase();
+  return AUTHORITATIVE_PROVIDER_CONTEXT_WINDOWS.get(key) ?? null;
 }
 
 /**

tests/unit/model-capabilities-registry.test.ts

@@ -207,3 +207,53 @@ test("Kimi K2.7 Code resolves full capabilities instead of the degraded import d
   assert.notEqual(ollama.contextWindow, 128000);
   assert.notEqual(ollama.maxOutputTokens, 8192);
 });
+
+test("GLM-5.2 context limits respect provider-hosted caps", () => {
+  modelsDevSync.saveModelsDevCapabilities({
+    huggingface: {
+      "zai-org/GLM-5.2": buildCapability({
+        limit_context: 128000,
+        limit_input: 128000,
+        limit_output: 128000,
+      }),
+    },
+    "cloudflare-ai": {
+      "@cf/zai-org/glm-5.2": buildCapability({
+        limit_context: 128000,
+        limit_input: 128000,
+        limit_output: 128000,
+      }),
+    },
+    zenmux: {
+      "z-ai/glm-5.2": buildCapability({
+        limit_context: 128000,
+        limit_input: 128000,
+        limit_output: 128000,
+      }),
+    },
+  });
+
+  for (const modelId of ["glm-5.2", "opencode-go/glm-5.2", "opencode/glm-5.2", "oc/glm-5.2"]) {
+    const capabilities = modelCapabilities.getResolvedModelCapabilities(modelId);
+    assert.equal(capabilities.contextWindow, 1000000, modelId);
+    assert.equal(capabilities.maxInputTokens, 1000000, modelId);
+  }
+
+  for (const modelId of ["zenmux/z-ai/glm-5.2", "zenmux/z-ai/glm-5.2-free"]) {
+    const capabilities = modelCapabilities.getResolvedModelCapabilities(modelId);
+    assert.equal(capabilities.contextWindow, 1000000, modelId);
+    assert.equal(capabilities.maxInputTokens, 1000000, modelId);
+  }
+
+  for (const modelId of ["cloudflare-ai/@cf/zai-org/glm-5.2", "cf/@cf/zai-org/glm-5.2"]) {
+    const capabilities = modelCapabilities.getResolvedModelCapabilities(modelId);
+    assert.equal(capabilities.contextWindow, 262144, modelId);
+    assert.equal(capabilities.maxInputTokens, 262144, modelId);
+  }
+
+  for (const modelId of ["huggingface/zai-org/GLM-5.2", "hf/zai-org/GLM-5.2"]) {
+    const capabilities = modelCapabilities.getResolvedModelCapabilities(modelId);
+    assert.equal(capabilities.contextWindow, 262144, modelId);
+    assert.equal(capabilities.maxInputTokens, 262144, modelId);
+  }
+});

tests/unit/models-catalog-route.test.ts

@@ -843,6 +843,99 @@ test("v1 models catalog includes synced non-Gemini provider models from discover
   assert.equal(syncedModel.context_length, 262144);
 });
 
+test("v1 models catalog advertises GLM-5.2 provider aliases with hosted context limits", async () => {
+  const hfConnection = await seedConnection("huggingface", {
+    name: "huggingface-glm52",
+    apiKey: "hf-key",
+  });
+  const cfConnection = await seedConnection("cloudflare-ai", {
+    name: "cloudflare-glm52",
+    apiKey: "cf-key",
+  });
+  const zenmuxConnection = await seedConnection("zenmux", {
+    name: "zenmux-glm52",
+    apiKey: "zen-key",
+  });
+  await seedConnection("opencode-go", {
+    name: "opencode-go-glm52",
+    apiKey: "go-key",
+  });
+
+  await modelsDb.replaceSyncedAvailableModelsForConnection(
+    "huggingface",
+    (hfConnection as any).id,
+    [
+      {
+        id: "zai-org/GLM-5.2",
+        name: "GLM 5.2",
+        source: "imported",
+        supportedEndpoints: ["chat"],
+        inputTokenLimit: 128000,
+        outputTokenLimit: 128000,
+      },
+    ]
+  );
+  await modelsDb.replaceSyncedAvailableModelsForConnection(
+    "cloudflare-ai",
+    (cfConnection as any).id,
+    [
+      {
+        id: "@cf/zai-org/glm-5.2",
+        name: "GLM 5.2",
+        source: "imported",
+        supportedEndpoints: ["chat"],
+        inputTokenLimit: 128000,
+        outputTokenLimit: 128000,
+      },
+    ]
+  );
+  await modelsDb.replaceSyncedAvailableModelsForConnection("zenmux", (zenmuxConnection as any).id, [
+    {
+      id: "z-ai/glm-5.2",
+      name: "GLM 5.2",
+      source: "imported",
+      supportedEndpoints: ["chat"],
+      inputTokenLimit: 128000,
+      outputTokenLimit: 128000,
+    },
+  ]);
+
+  try {
+    modelsDevSync.saveModelsDevCapabilities({
+      huggingface: {
+        "zai-org/GLM-5.2": capability({ limit_context: 128000, limit_input: 128000 }),
+      },
+      "cloudflare-ai": {
+        "@cf/zai-org/glm-5.2": capability({ limit_context: 128000, limit_input: 128000 }),
+      },
+      zenmux: {
+        "z-ai/glm-5.2": capability({ limit_context: 128000, limit_input: 128000 }),
+      },
+    });
+
+    const response = await v1ModelsCatalog.getUnifiedModelsResponse(
+      new Request("http://localhost/api/v1/models")
+    );
+    const body = (await response.json()) as any;
+    const byId = new Map(body.data.map((item) => [item.id, item]));
+
+    for (const [id, expectedContext] of [
+      ["huggingface/zai-org/GLM-5.2", 262144],
+      ["cloudflare-ai/@cf/zai-org/glm-5.2", 262144],
+      ["opencode-go/glm-5.2", 1000000],
+      ["zenmux/z-ai/glm-5.2", 1000000],
+    ] as const) {
+      const model = byId.get(id) as any;
+      assert.ok(model, `expected ${id} in catalog`);
+      assert.equal(model.context_length, expectedContext, id);
+      assert.equal(model.max_input_tokens, expectedContext, id);
+      assert.notEqual(model.context_length, 128000, id);
+    }
+  } finally {
+    modelsDevSync.saveModelsDevCapabilities({});
+  }
+});
+
 test("v1 models catalog includes media, moderation, rerank, video, and music models for active providers", async () => {
   await seedConnection("openai", { name: "openai-media" });
   await seedConnection("cohere", { name: "cohere-rerank" });