fix(cli): suppress LangSmith trace for _context_tokens state writes (#3317)

`_context_tokens` is declared with `PrivateStateAttr`, which keeps it
out of the graph's input/output schemas, but `Pregel.aupdate_state`
still emits its own top-level `UpdateState` run on every turn — so the
count surfaces as a noisy standalone trace in LangSmith on each LLM
response and offload.

Wrap the `aupdate_state` call in `_persist_context_tokens` with
`langsmith.tracing_context(enabled=False)` so the internal bookkeeping
write is fully suppressed from the active LangSmith project while still
being checkpointed for thread resume.

_Opened collaboratively by Mason Daugherty and open-swe._

Co-authored-by: open-swe[bot] <open-swe@users.noreply.github.com>
Co-authored-by: Mason Daugherty <61371264+mdrxy@users.noreply.github.com>
Co-authored-by: Mason Daugherty <mason@langchain.dev>

libs/cli/deepagents_cli/textual_adapter.py

@@ -1432,13 +1432,22 @@ async def _persist_context_tokens(
 ) -> None:
     """Best-effort persist of the context token count into graph state.
 
+    The `aupdate_state` call is wrapped in `tracing_context(enabled=False)` so
+    this purely-internal bookkeeping write does not surface as a separate
+    `UpdateState` run in LangSmith. `_context_tokens` is already marked
+    `PrivateStateAttr`, but `aupdate_state` itself creates its own traced run
+    that would otherwise clutter the project's traces.
+
     Args:
         agent: The LangGraph agent (must support `aupdate_state`).
         config: Runnable config with `thread_id`.
         tokens: Total context tokens to persist.
     """
+    from langsmith import tracing_context
+
     try:
-        await agent.aupdate_state(config, {"_context_tokens": tokens})
+        with tracing_context(enabled=False):
+            await agent.aupdate_state(config, {"_context_tokens": tokens})
     except (httpx.TransportError, httpx.TimeoutException) as e:
         logger.warning(
             "Could not persist _context_tokens=%d (network): %s; "

libs/cli/tests/unit_tests/test_token_tracker.py

@@ -123,3 +123,28 @@ class TestPersistContextTokens:
 
         # Should not raise
         await _persist_context_tokens(agent, config, 1000)  # type: ignore[arg-type]
+
+    async def test_disables_tracing_during_update(self):
+        """`aupdate_state` should run with LangSmith tracing disabled.
+
+        The token-count write is a private bookkeeping update; surfacing it as a
+        standalone `UpdateState` run in LangSmith clutters traces.
+        """
+        from unittest.mock import AsyncMock
+
+        from langsmith import get_tracing_context
+
+        from deepagents_cli.textual_adapter import _persist_context_tokens
+
+        captured: dict[str, object] = {}
+
+        async def _capture(*_args: object, **_kwargs: object) -> None:  # noqa: RUF029  # AsyncMock side_effect must be a coroutine function
+            captured["enabled"] = get_tracing_context().get("enabled")
+
+        agent = AsyncMock()
+        agent.aupdate_state.side_effect = _capture
+        config = {"configurable": {"thread_id": "t-1"}}
+
+        await _persist_context_tokens(agent, config, 4200)  # type: ignore[arg-type]
+
+        assert captured["enabled"] is False