fix(catalog): honour a member's max_output_tokens override in combo metadata

changelog.d/fixes/16556-combo-max-output-override.md

@@ -0,0 +1 @@
+- **fix(catalog):** a combo's `max_output_tokens` now honours a member's `max_output_tokens` capability override, as the per-model entry already did ([#16556](https://github.com/diegosouzapw/OmniRoute/pull/16556)) — thanks @pacocartones

src/app/api/v1/models/catalog.ts

@@ -670,11 +670,15 @@ async function buildUnifiedModelsResponseCore(
       const maxInputTokens = isPositiveFiniteNumber(canonical.limits.maxInputTokens)
         ? canonical.limits.maxInputTokens
         : contextLength;
-      const maxOutputTokens = isPositiveFiniteNumber(synced?.limit_output)
-        ? synced.limit_output
-        : isPositiveFiniteNumber(spec?.maxOutputTokens)
-          ? spec.maxOutputTokens
-          : undefined;
+      // #16515: canonical.limits.maxOutputTokens already applies an operator's
+      // max_output_tokens override, as the per-model catalog entry does.
+      const maxOutputTokens = isPositiveFiniteNumber(canonical.limits.maxOutputTokens)
+        ? canonical.limits.maxOutputTokens
+        : isPositiveFiniteNumber(synced?.limit_output)
+          ? synced.limit_output
+          : isPositiveFiniteNumber(spec?.maxOutputTokens)
+            ? spec.maxOutputTokens
+            : undefined;
 
       const syncedVision =
         typeof synced?.attachment === "boolean"

tests/unit/16515-combo-max-output-override.test.ts

@@ -0,0 +1,72 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+import fs from "node:fs";
+import os from "node:os";
+import path from "node:path";
+
+const TEST_DATA_DIR = fs.mkdtempSync(path.join(os.tmpdir(), "omniroute-16515-"));
+process.env.DATA_DIR = TEST_DATA_DIR;
+process.env.API_KEY_SECRET = process.env.API_KEY_SECRET || "catalog-test-secret";
+process.env.CATALOG_BUILD_TIMEOUT_MS = process.env.CATALOG_BUILD_TIMEOUT_MS || "120000";
+
+const core = await import("../../src/lib/db/core.ts");
+const combosDb = await import("../../src/lib/db/combos.ts");
+const overridesDb = await import("../../src/lib/db/modelCapabilityOverrides.ts");
+const modelsDevSync = await import("../../src/lib/modelsDevSync.ts");
+const v1ModelsCatalog = await import("../../src/app/api/v1/models/catalog.ts");
+
+function capability(limitOutput: number) {
+  return {
+    tool_call: true,
+    reasoning: null,
+    attachment: null,
+    structured_output: null,
+    temperature: null,
+    modalities_input: JSON.stringify(["text"]),
+    modalities_output: JSON.stringify(["text"]),
+    knowledge_cutoff: null,
+    release_date: null,
+    last_updated: null,
+    status: null,
+    family: null,
+    open_weights: null,
+    limit_context: 1_000_000,
+    limit_input: null,
+    limit_output: limitOutput,
+    interleaved_field: null,
+  };
+}
+
+test.after(() => {
+  core.resetDbInstance();
+  fs.rmSync(TEST_DATA_DIR, { recursive: true, force: true, maxRetries: 5, retryDelay: 100 });
+});
+
+test("#16515 a combo's max_output_tokens honours a member's max_output_tokens override", async () => {
+  modelsDevSync.saveModelsDevCapabilities({
+    openai: { "override-member": capability(1_048_576) },
+    gemini: { "plain-member": capability(384_000) },
+  });
+  assert.equal(
+    overridesDb.setModelCapabilityOverride("openai/override-member", "max_output_tokens", 65_536),
+    true
+  );
+  await combosDb.createCombo({
+    name: "override-router",
+    strategy: "priority",
+    models: ["openai/override-member", "gemini/plain-member"],
+  });
+
+  const response = await v1ModelsCatalog.getUnifiedModelsResponse(
+    new Request("http://localhost/api/v1/models")
+  );
+  const body = (await response.json()) as {
+    data: Array<{ id: string; max_output_tokens?: number }>;
+  };
+  const combo = body.data.find((item) => item.id === "override-router");
+
+  assert.equal(response.status, 200);
+  assert.ok(combo);
+  // min(65536 after the override, 384000), not min(1048576 raw, 384000)
+  assert.equal(combo.max_output_tokens, 65_536);
+});