Add Braintrust tracing as experimental drop-in environment variants

pyproject.toml

@@ -96,6 +96,9 @@ browser = [
 renderers = [
     "renderers>=0.1.6",
 ]
+braintrust = [
+    "braintrust>=0.0.160",
+]
 rl = [
     "torch>=2.8.0,<2.9.0",
     "transformers>=4.56.2",
@@ -230,6 +233,12 @@ invalid-method-override = "ignore"
 invalid-assignment = "ignore"
 not-iterable = "ignore"
 
+[[tool.ty.overrides]]
+include = ["verifiers/envs/experimental/braintrust_tracing/**"]
+
+[tool.ty.overrides.rules]
+unresolved-import = "ignore"
+
 [tool.coverage.run]
 source = ["verifiers"]
 omit = [

verifiers/envs/experimental/braintrust_tracing/__init__.py

@@ -0,0 +1,24 @@
+"""Experimental Braintrust tracing variants of the core environment classes.
+
+Usage::
+
+    from verifiers.envs.experimental.braintrust_tracing.stateful_tool_env import StatefulToolEnv
+
+These classes are drop-in replacements for their non-tracing counterparts.
+Set ``BRAINTRUST_API_KEY`` and optionally ``VF_BRAINTRUST_PROJECT`` to enable
+trace logging to Braintrust.
+"""
+
+from verifiers.envs.experimental.braintrust_tracing.environment import Environment
+from verifiers.envs.experimental.braintrust_tracing.multiturn_env import MultiTurnEnv
+from verifiers.envs.experimental.braintrust_tracing.stateful_tool_env import (
+    StatefulToolEnv,
+)
+from verifiers.envs.experimental.braintrust_tracing.tool_env import ToolEnv
+
+__all__ = [
+    "Environment",
+    "MultiTurnEnv",
+    "ToolEnv",
+    "StatefulToolEnv",
+]