From 6afb392daadea500077952ebdb6773537d6f4ae5 Mon Sep 17 00:00:00 2001
From: Zhanibek Datbayev <itomatik@gmail.com>
Date: Mon, 12 Oct 2026 19:19:13 -0700
Subject: [PATCH] feat(models): add canonical Drex 2.0 decision model

---
 models/nace-ai/drex-v2.0.toml                 | 40 +++++++++++++++++++
 .../core/src/sync/providers/openrouter.ts     |  5 ++-
 packages/core/test/sync.test.ts               | 22 ++++++++++
 .../openrouter/models/nace-ai/drex-v2.0.toml  | 20 +---------
 4 files changed, 66 insertions(+), 21 deletions(-)
 create mode 100644 models/nace-ai/drex-v2.0.toml

diff --git a/models/nace-ai/drex-v2.0.toml b/models/nace-ai/drex-v2.0.toml
new file mode 100644
index 00000000000..d4464cc39a7
--- /dev/null
+++ b/models/nace-ai/drex-v2.0.toml
@@ -0,0 +1,40 @@
+# Sources:
+# - https://huggingface.co/nace-ai/drex-v2.0
+# - https://github.com/nace-ai/drex-decision-models/blob/main/docs/context-length.md
+# - https://console.nace.ai/docs/drex/reference/models
+# Context is the model's maximum state-plus-one-question length, not the
+# first-party API's smaller Drex 2.0 limit before fallback to Drex 1.5.
+name = "Drex 2.0"
+type = "decision"
+description = "35B mixture-of-experts System One decision model with 3B active parameters, returning typed, calibrated probabilities over text or structured state without generating text"
+release_date = "2026-10-06"
+last_updated = "2026-10-12"
+attachment = false
+reasoning = false
+temperature = false
+tool_call = false
+structured_output = true
+open_weights = true
+license = "Nace.AI Open RAIL-M"
+
+[limit]
+context = 131_072
+output = 0
+
+[modalities]
+input = ["text"]
+output = ["text"]
+
+[[links]]
+label = "Documentation"
+url = "https://github.com/nace-ai/drex-decision-models"
+type = "docs"
+
+[[links]]
+label = "License"
+url = "https://huggingface.co/nace-ai/drex-v2.0/blob/main/LICENSE"
+type = "license"
+
+[[weights]]
+url = "https://huggingface.co/nace-ai/drex-v2.0"
+format = "safetensors"
diff --git a/packages/core/src/sync/providers/openrouter.ts b/packages/core/src/sync/providers/openrouter.ts
index f90874363fa..4bfa6d06306 100644
--- a/packages/core/src/sync/providers/openrouter.ts
+++ b/packages/core/src/sync/providers/openrouter.ts
@@ -266,10 +266,11 @@ export function buildOpenRouterModel(
   const limit = {
     context,
     input: existing?.limit?.input,
-    output: OUTPUT_LIMIT_OVERRIDES[model.id]
+    // Decision models evaluate state without generating completion tokens.
+    output: decision ? 0 : (OUTPUT_LIMIT_OVERRIDES[model.id]
       ?? model.top_provider.max_completion_tokens
       ?? existing?.limit?.output
-      ?? context,
+      ?? context),
   };
   const canonical = existing?.base_model ?? baseModel ?? resolveCanonicalBaseModel(model.id);
 
diff --git a/packages/core/test/sync.test.ts b/packages/core/test/sync.test.ts
index ae322e72769..e5396fc6d9e 100644
--- a/packages/core/test/sync.test.ts
+++ b/packages/core/test/sync.test.ts
@@ -5189,6 +5189,7 @@ test("syncs OpenRouter decision models with no supported parameters as decision
     description: "Decision model for typed evaluation of shared state",
     modalities: { input: ["text", "image"], output: ["text"] },
     cost: { input: 0.15, output: 0 },
+    limit: { context: 65_536, output: 0 },
   });
   expect(openrouter.translateModel(openRouterModel(), {
     existing: () => undefined,
@@ -5214,6 +5215,27 @@ test("factors OpenRouter decision models onto decision lab metadata without a ch
   expect(translated?.model).toMatchObject({ base_model: "liquid/d1", cost: { input: 0.04, output: 0 } });
   expect(translated?.model).not.toHaveProperty("type"); // inherited from lab metadata
   expect(translated?.model).not.toHaveProperty("description");
+  expect(translated?.model).not.toHaveProperty("limit");
+});
+
+test("inherits canonical Drex2 metadata instead of retaining an OpenRouter completion limit", () => {
+  for (const existing of [undefined, { limit: { output: 117_964 } }]) {
+    const model = buildOpenRouterModel(openRouterModel({
+      id: "nace-ai/drex-v2.0",
+      name: "Nace AI: Drex v2.0",
+      knowledge_cutoff: null,
+      context_length: 131_072,
+      architecture: { input_modalities: ["text"], output_modalities: ["decisions"] },
+      pricing: { prompt: "0.00000006", completion: "0" },
+      top_provider: { context_length: 131_072, max_completion_tokens: 117_964 },
+      supported_parameters: [],
+    }), existing);
+
+    expect(model).toMatchObject({ base_model: "nace-ai/drex-v2.0", cost: { input: 0.06, output: 0 } });
+    for (const inherited of ["type", "description", "limit", "structured_output", "open_weights"]) {
+      expect(model).not.toHaveProperty(inherited);
+    }
+  }
 });
 
 test("parses nullable EmpirioLabs release dates", () => {
diff --git a/providers/openrouter/models/nace-ai/drex-v2.0.toml b/providers/openrouter/models/nace-ai/drex-v2.0.toml
index 5d8ec7929f5..7575033ede9 100644
--- a/providers/openrouter/models/nace-ai/drex-v2.0.toml
+++ b/providers/openrouter/models/nace-ai/drex-v2.0.toml
@@ -1,23 +1,5 @@
-type = "decision"
-name = "Drex v2.0"
-description = "Decision model for typed evaluation of shared state"
-release_date = "2026-10-12"
-last_updated = "2026-10-12"
-attachment = false
-reasoning = false
-temperature = false
-tool_call = false
-structured_output = false
-open_weights = false
+base_model = "nace-ai/drex-v2.0"
 
 [cost]
 input = 0.06
 output = 0
-
-[limit]
-context = 131_072
-output = 117_964
-
-[modalities]
-input = ["text"]
-output = ["text"]