Resolve repo-architect models from GitHub catalog with available-only fallback selection and preserve explicit override

.github/workflows/repo-architect.yml

@@ -77,14 +77,96 @@ jobs:
         run: |
           mkdir -p .agent docs/repo_architect
 
+      - name: Resolve GitHub Models configuration
+        env:
+          GITHUB_TOKEN: ${{ github.token }}
+        run: |
+          python - <<'PY'
+          import json
+          import os
+          import urllib.request
+
+          order = [
+              "anthropic/claude-sonnet-4.6",
+              "anthropic/claude-sonnet-4.5",
+              "openai/gpt-4.1",
+          ]
+          secondary = "google/gemini-3-pro"
+          available = set()
+          catalog_ok = False
+          try:
+              req = urllib.request.Request(
+                  "https://models.github.ai/catalog/models",
+                  headers={
+                      "Authorization": f"Bearer {os.environ['GITHUB_TOKEN']}",
+                      "Accept": "application/json",
+                      "User-Agent": "repo-architect-workflow",
+                  },
+              )
+              with urllib.request.urlopen(req, timeout=30) as resp:
+                  payload = json.loads(resp.read().decode("utf-8"))
+              models = payload.get("data", payload) if isinstance(payload, dict) else payload
+              if isinstance(models, list):
+                  catalog_ok = True
+                  for item in models:
+                      if isinstance(item, dict):
+                          model_id = item.get("id") or item.get("name") or item.get("model")
+                          if isinstance(model_id, str) and model_id:
+                              available.add(model_id)
+          except Exception as exc:
+              print(f"warning: GitHub Models catalog lookup failed; using defaults ({exc})")
+
+          def first_available(candidates):
+              for candidate in candidates:
+                  if candidate in available:
+                      return candidate
+              return None
+
+          def deterministic_available(exclude=None):
+              candidates = sorted(m for m in available if m != exclude)
+              return candidates[0] if candidates else None
+
+          if catalog_ok and available:
+              preferred = (
+                  first_available(order)
+                  or (secondary if secondary in available else None)
+                  or deterministic_available()
+              )
+          else:
+              preferred = order[0]
+
+          if catalog_ok and available:
+              if secondary in available and secondary != preferred:
+                  fallback = secondary
+              else:
+                  fallback = (
+                      first_available([c for c in order if c != preferred])
+                      or deterministic_available(exclude=preferred)
+                      or preferred
+                  )
+          else:
+              fallback = secondary
+
+          if not isinstance(preferred, str) or not preferred:
+              preferred = order[0]
+          if not isinstance(fallback, str) or not fallback:
+              fallback = secondary if secondary != preferred else order[-1]
+
+          env_file = os.environ.get("GITHUB_ENV")
+          if not env_file:
+              raise RuntimeError("GITHUB_ENV is not set; this internal workflow step must run inside GitHub Actions with environment-file support.")
+          with open(env_file, "a", encoding="utf-8") as fh:
+              fh.write(f"REPO_ARCHITECT_PREFERRED_MODEL={preferred}\n")
+              fh.write(f"REPO_ARCHITECT_FALLBACK_MODEL={fallback}\n")
+          print(f"selected preferred={preferred} fallback={fallback}")
+          PY
+
       - name: Run repo architect
         env:
           GITHUB_TOKEN: ${{ github.token }}
           GITHUB_REPO: ${{ github.repository }}
           GITHUB_BASE_BRANCH: ${{ github.event.repository.default_branch }}
           REPO_ARCHITECT_BRANCH_SUFFIX: ${{ github.run_id }}-${{ github.run_attempt }}
-          REPO_ARCHITECT_PREFERRED_MODEL: openai/gpt-5.4
-          REPO_ARCHITECT_FALLBACK_MODEL: openai/gpt-4.1
         run: |
           MODE="${{ github.event.inputs.mode }}"
           MODEL="${{ github.event.inputs.github_model }}"

repo_architect.py

@@ -60,8 +60,8 @@
 }
 
 # Model selection defaults
-DEFAULT_PREFERRED_MODEL = "openai/gpt-5.4"
-DEFAULT_FALLBACK_MODEL = "openai/gpt-4.1"
+DEFAULT_PREFERRED_MODEL = "anthropic/claude-sonnet-4.6"
+DEFAULT_FALLBACK_MODEL = "google/gemini-3-pro"
 # Substrings in HTTP error bodies that indicate the model itself is unavailable (not a transient error)
 _MODEL_UNAVAILABLE_SIGNALS = frozenset({
     "unknown_model", "model_not_found", "unsupported_model", "unsupported model",
@@ -697,7 +697,7 @@ def build_analysis(root: pathlib.Path) -> Dict[str, Any]:
 # -----------------------------
 
 def enrich_with_github_models(config: Config, analysis: Dict[str, Any]) -> Dict[str, Any]:
-    preferred = config.preferred_model or config.github_model
+    preferred = config.github_model or config.preferred_model
     fallback = config.fallback_model
     meta: Dict[str, Any] = {
         "enabled": False,
@@ -975,7 +975,7 @@ def build_parse_errors_plan(config: Config, analysis: Dict[str, Any]) -> Optiona
     errors = analysis.get("parse_error_files", [])
     if not errors:
         return None
-    preferred = config.preferred_model or config.github_model
+    preferred = config.github_model or config.preferred_model
     if not config.github_token or not preferred:
         return None
     fallback = config.fallback_model
@@ -1042,7 +1042,7 @@ def build_import_cycles_plan(config: Config, analysis: Dict[str, Any]) -> Option
     cycles = analysis.get("cycles", [])
     if not cycles:
         return None
-    preferred = config.preferred_model or config.github_model
+    preferred = config.github_model or config.preferred_model
     if not config.github_token or not preferred:
         return None
     fallback = config.fallback_model
@@ -1128,7 +1128,7 @@ def build_entrypoint_consolidation_plan(config: Config, analysis: Dict[str, Any]
     backend_eps = clusters.get("backend_servers", [])
     if len(backend_eps) < _ENTRYPOINT_CONSOLIDATION_THRESHOLD:
         return None
-    preferred = config.preferred_model or config.github_model
+    preferred = config.github_model or config.preferred_model
     if not config.github_token or not preferred:
         return None
     fallback = config.fallback_model
@@ -1482,14 +1482,96 @@ def workflow_yaml(secret_env_names: Sequence[str], cron: str, github_model: Opti
         run: |
           mkdir -p .agent docs/repo_architect
 
+      - name: Resolve GitHub Models configuration
+        env:
+          GITHUB_TOKEN: ${{{{ github.token }}}}
+        run: |
+          python - <<'PY'
+          import json
+          import os
+          import urllib.request
+
+          order = [
+              "anthropic/claude-sonnet-4.6",
+              "anthropic/claude-sonnet-4.5",
+              "openai/gpt-4.1",
+          ]
+          secondary = "google/gemini-3-pro"
+          available = set()
+          catalog_ok = False
+          try:
+              req = urllib.request.Request(
+                  "https://models.github.ai/catalog/models",
+                  headers={{
+                      "Authorization": f"Bearer {{os.environ['GITHUB_TOKEN']}}",
+                      "Accept": "application/json",
+                      "User-Agent": "repo-architect-workflow",
+                  }},
+              )
+              with urllib.request.urlopen(req, timeout=30) as resp:
+                  payload = json.loads(resp.read().decode("utf-8"))
+              models = payload.get("data", payload) if isinstance(payload, dict) else payload
+              if isinstance(models, list):
+                  catalog_ok = True
+                  for item in models:
+                      if isinstance(item, dict):
+                          model_id = item.get("id") or item.get("name") or item.get("model")
+                          if isinstance(model_id, str) and model_id:
+                              available.add(model_id)
+          except Exception as exc:
+              print(f"warning: GitHub Models catalog lookup failed; using defaults ({{exc}})")
+
+          def first_available(candidates):
+              for candidate in candidates:
+                  if candidate in available:
+                      return candidate
+              return None
+
+          def deterministic_available(exclude=None):
+              candidates = sorted(m for m in available if m != exclude)
+              return candidates[0] if candidates else None
+
+          if catalog_ok and available:
+              preferred = (
+                  first_available(order)
+                  or (secondary if secondary in available else None)
+                  or deterministic_available()
+              )
+          else:
+              preferred = order[0]
+
+          if catalog_ok and available:
+              if secondary in available and secondary != preferred:
+                  fallback = secondary
+              else:
+                  fallback = (
+                      first_available([c for c in order if c != preferred])
+                      or deterministic_available(exclude=preferred)
+                      or preferred
+                  )
+          else:
+              fallback = secondary
+
+          if not isinstance(preferred, str) or not preferred:
+              preferred = order[0]
+          if not isinstance(fallback, str) or not fallback:
+              fallback = secondary if secondary != preferred else order[-1]
+
+          env_file = os.environ.get("GITHUB_ENV")
+          if not env_file:
+              raise RuntimeError("GITHUB_ENV is not set; this internal workflow step must run inside GitHub Actions with environment-file support.")
+          with open(env_file, "a", encoding="utf-8") as fh:
+              fh.write(f"REPO_ARCHITECT_PREFERRED_MODEL={{preferred}}\\n")
+              fh.write(f"REPO_ARCHITECT_FALLBACK_MODEL={{fallback}}\\n")
+          print(f"selected preferred={{preferred}} fallback={{fallback}}")
+          PY
+
       - name: Run repo architect
         env:
           GITHUB_TOKEN: ${{{{ github.token }}}}
           GITHUB_REPO: ${{{{ github.repository }}}}
           GITHUB_BASE_BRANCH: ${{{{ github.event.repository.default_branch }}}}
           REPO_ARCHITECT_BRANCH_SUFFIX: ${{{{ github.run_id }}}}-${{{{ github.run_attempt }}}}
-          REPO_ARCHITECT_PREFERRED_MODEL: openai/gpt-5.4
-          REPO_ARCHITECT_FALLBACK_MODEL: openai/gpt-4.1
 {extra_env}        run: |
           MODE="${{{{ github.event.inputs.mode }}}}"
           MODEL="${{{{ github.event.inputs.github_model }}}}"

tests/test_repo_architect.py

@@ -250,7 +250,72 @@ def side_effect(token: str, model: str, messages: list) -> dict:
 
 
 # ---------------------------------------------------------------------------
-# 3. Syntax validation of generated Python (ast.parse gate)
+# 3. Model configuration behaviour
+# ---------------------------------------------------------------------------
+
+class TestModelConfiguration(unittest.TestCase):
+    def test_build_config_uses_env_models_when_github_model_blank(self) -> None:
+        env = dict(os.environ)
+        env.pop("GITHUB_MODEL", None)
+        env["REPO_ARCHITECT_PREFERRED_MODEL"] = "anthropic/claude-sonnet-4.6"
+        env["REPO_ARCHITECT_FALLBACK_MODEL"] = "google/gemini-3-pro"
+        with patch.object(ra, "discover_git_root", return_value=pathlib.Path("/tmp/repo")):
+            with patch.dict(os.environ, env, clear=True):
+                config = ra.build_config(ra.parse_args([]))
+        self.assertIsNone(config.github_model)
+        self.assertEqual(config.preferred_model, "anthropic/claude-sonnet-4.6")
+        self.assertEqual(config.fallback_model, "google/gemini-3-pro")
+
+    def test_github_model_override_takes_precedence_over_preferred(self) -> None:
+        analysis = {
+            "architecture_score": 0.8,
+            "cycles": [],
+            "parse_error_files": [],
+            "entrypoint_paths": [],
+            "roadmap": [],
+        }
+        response = {"choices": [{"message": {"content": "ok"}}], "model": "openai/manual-override"}
+        with tempfile.TemporaryDirectory() as tmp:
+            root = _make_git_root(tmp)
+            config = _make_config(
+                root,
+                github_token="tok",
+                github_model="openai/manual-override",
+                preferred_model="anthropic/claude-sonnet-4.6",
+                fallback_model="google/gemini-3-pro",
+            )
+            with patch.object(
+                ra,
+                "call_models_with_fallback_or_none",
+                return_value=(response, "openai/manual-override", None, False),
+            ) as mocked_call:
+                meta = ra.enrich_with_github_models(config, analysis)
+        self.assertEqual(mocked_call.call_args.args[1], "openai/manual-override")
+        self.assertEqual(mocked_call.call_args.args[2], "google/gemini-3-pro")
+        self.assertEqual(meta["requested_model"], "openai/manual-override")
+        self.assertEqual(meta["actual_model"], "openai/manual-override")
+
+    def test_workflow_yaml_resolves_models_via_catalog_and_keeps_blank_override_logic(self) -> None:
+        workflow = ra.workflow_yaml([], "17 * * * *", None)
+        self.assertIn("Resolve GitHub Models configuration", workflow)
+        self.assertIn("https://models.github.ai/catalog/models", workflow)
+        self.assertIn("catalog_ok = False", workflow)
+        self.assertIn('"anthropic/claude-sonnet-4.6"', workflow)
+        self.assertIn('"anthropic/claude-sonnet-4.5"', workflow)
+        self.assertIn('"openai/gpt-4.1"', workflow)
+        self.assertIn('secondary = "google/gemini-3-pro"', workflow)
+        self.assertIn("def deterministic_available(exclude=None):", workflow)
+        self.assertIn("or deterministic_available()", workflow)
+        self.assertIn("or deterministic_available(exclude=preferred)", workflow)
+        self.assertIn("or preferred", workflow)
+        self.assertIn("REPO_ARCHITECT_PREFERRED_MODEL={preferred}", workflow)
+        self.assertIn("REPO_ARCHITECT_FALLBACK_MODEL={fallback}", workflow)
+        self.assertIn('if [ -n "$MODEL" ]; then EXTRA_ARGS="$EXTRA_ARGS --github-model $MODEL"; fi', workflow)
+        self.assertIn("models: read", workflow)
+
+
+# ---------------------------------------------------------------------------
+# 4. Syntax validation of generated Python (ast.parse gate)
 # ---------------------------------------------------------------------------
 
 class TestSyntaxValidationGate(unittest.TestCase):
@@ -313,7 +378,7 @@ def test_build_parse_errors_plan_accepts_valid_fix(self) -> None:
 
 
 # ---------------------------------------------------------------------------
-# 4. Campaign aggregation behaviour
+# 5. Campaign aggregation behaviour
 # ---------------------------------------------------------------------------
 
 class TestCampaignAggregation(unittest.TestCase):