chore(weave): Env var for Remote Scoring result schema

tests/trace_server/test_environment.py

@@ -6,6 +6,7 @@
     DEFAULT_REMOTE_SCORER_HTTP_TIMEOUT_SECONDS,
     REMOTE_SCORER_ALLOW_INSECURE_HTTP_ENV,
     REMOTE_SCORER_ALLOWED_HOSTS_ENV,
+    REMOTE_SCORER_REQUIRE_STRUCTURED_RESULT_SCHEMA_ENV,
     REMOTE_SCORER_VALIDATE_HOSTS_ENV,
     VALID_CALLS_SHARD_KEYS,
     kafka_producer_max_buffer_size,
@@ -19,6 +20,7 @@
     wf_scoring_worker_remote_scorer_bearer_token,
     wf_scoring_worker_remote_scorer_enabled,
     wf_scoring_worker_remote_scorer_http_timeout_seconds,
+    wf_scoring_worker_remote_scorer_require_structured_result_schema,
     wf_scoring_worker_remote_scorer_validate_hosts,
 )
 
@@ -269,3 +271,25 @@ def test_wf_scoring_worker_remote_scorer_allow_insecure_http(monkeypatch):
     assert wf_scoring_worker_remote_scorer_allow_insecure_http() is False
     monkeypatch.setenv(key, "1")
     assert wf_scoring_worker_remote_scorer_allow_insecure_http() is False
+
+
+@pytest.mark.disable_logging_error_check
+def test_wf_scoring_worker_remote_scorer_require_structured_result_schema(
+    monkeypatch,
+):
+    """Structured result schema enforcement is enabled by default; only false disables it."""
+    key = REMOTE_SCORER_REQUIRE_STRUCTURED_RESULT_SCHEMA_ENV
+    monkeypatch.delenv(key, raising=False)
+    assert wf_scoring_worker_remote_scorer_require_structured_result_schema() is True
+
+    monkeypatch.setenv(key, "false")
+    assert wf_scoring_worker_remote_scorer_require_structured_result_schema() is False
+    monkeypatch.setenv(key, "False")
+    assert wf_scoring_worker_remote_scorer_require_structured_result_schema() is False
+
+    monkeypatch.setenv(key, "true")
+    assert wf_scoring_worker_remote_scorer_require_structured_result_schema() is True
+    monkeypatch.setenv(key, "")
+    assert wf_scoring_worker_remote_scorer_require_structured_result_schema() is True
+    monkeypatch.setenv(key, "0")
+    assert wf_scoring_worker_remote_scorer_require_structured_result_schema() is True

weave/trace_server/environment.py

@@ -159,6 +159,9 @@ def wf_scoring_worker_remote_scorer_bearer_token() -> str | None:
 REMOTE_SCORER_ALLOW_INSECURE_HTTP_ENV = (
     "WF_SCORING_WORKER_REMOTE_SCORER_ALLOW_INSECURE_HTTP"
 )
+REMOTE_SCORER_REQUIRE_STRUCTURED_RESULT_SCHEMA_ENV = (
+    "WF_SCORING_WORKER_REMOTE_SCORER_REQUIRE_STRUCTURED_RESULT_SCHEMA"
+)
 
 
 def wf_scoring_worker_remote_scorer_enabled() -> bool:
@@ -223,6 +226,21 @@ def wf_scoring_worker_remote_scorer_allow_insecure_http() -> bool:
     )
 
 
+def wf_scoring_worker_remote_scorer_require_structured_result_schema() -> bool:
+    """Whether remote scorer results must match the structured scorer schema.
+
+    Defaults to true to nudge new RemoteScorer users onto the typed scorer
+    result shape. Set to ``false`` only for controlled compatibility testing or
+    emergency operational bypasses.
+    """
+    return (
+        os.environ.get(
+            REMOTE_SCORER_REQUIRE_STRUCTURED_RESULT_SCHEMA_ENV, "true"
+        ).lower()
+        != "false"
+    )
+
+
 # Clickhouse Settings