fix: use thread-level LangSmith URLs instead of run-level URLs to fix broken trace links (#1217)

* fix: use thread-level LangSmith URLs instead of run-level URLs to fix broken trace links

* linting

agent/utils/langsmith.py

@@ -20,11 +20,13 @@ def _compose_langsmith_project_url() -> str:
     return f"{host_url}/o/{tenant_id}/projects/p/{project_id}"
 
 
-def get_langsmith_trace_url(run_id: str) -> str | None:
-    """Build the LangSmith trace URL for a given run ID."""
+def get_langsmith_trace_url(thread_id: str) -> str | None:
+    """Build the LangSmith thread URL for a given thread ID."""
     try:
-        base = _compose_langsmith_project_url()
-        return f"{base}?peek={run_id}&peeked_trace={run_id}"
+        project_url = _compose_langsmith_project_url()
+        return f"{project_url}/t/{thread_id}"
     except Exception:  # noqa: BLE001
-        logger.warning("Failed to build LangSmith trace URL for run %s", run_id, exc_info=True)
+        logger.warning(
+            "Failed to build LangSmith trace URL for thread %s", thread_id, exc_info=True
+        )
         return None

agent/utils/linear.py

@@ -63,15 +63,23 @@ async def comment_on_linear_issue(
     return bool(result.get("commentCreate", {}).get("success"))
 
 
-async def post_linear_trace_comment(issue_id: str, run_id: str, triggering_comment_id: str) -> None:
+async def post_linear_trace_comment(
+    issue_id: str, thread_id: str, triggering_comment_id: str
+) -> None:
     """Post a trace URL comment on a Linear issue."""
-    trace_url = get_langsmith_trace_url(run_id)
+    trace_url = get_langsmith_trace_url(thread_id)
     if trace_url:
         await comment_on_linear_issue(
             issue_id,
             f"On it! [View trace]({trace_url})",
             parent_id=triggering_comment_id or None,
         )
+    else:
+        await comment_on_linear_issue(
+            issue_id,
+            "On it!",
+            parent_id=triggering_comment_id or None,
+        )
 
 
 async def list_teams() -> dict[str, Any]:

agent/utils/slack.py

@@ -365,10 +365,12 @@ async def fetch_slack_thread_messages(channel_id: str, thread_ts: str) -> list[d
     return messages
 
 
-async def post_slack_trace_reply(channel_id: str, thread_ts: str, run_id: str) -> None:
+async def post_slack_trace_reply(channel_id: str, thread_ts: str, thread_id: str) -> None:
     """Post a trace URL reply in a Slack thread."""
-    trace_url = get_langsmith_trace_url(run_id)
+    trace_url = get_langsmith_trace_url(thread_id)
     if trace_url:
         await post_slack_thread_reply(
             channel_id, thread_ts, f"Working on it! <{trace_url}|View trace>"
         )
+    else:
+        await post_slack_thread_reply(channel_id, thread_ts, "Working on it!")

agent/webapp.py

@@ -675,13 +675,13 @@ async def process_linear_issue(  # noqa: PLR0912, PLR0915
             langgraph_client = get_client(url=LANGGRAPH_URL)
             runs = await langgraph_client.runs.list(thread_id, limit=1)
             if runs:
-                await post_linear_trace_comment(issue_id, runs[0]["run_id"], triggering_comment_id)
+                await post_linear_trace_comment(issue_id, thread_id, triggering_comment_id)
         else:
             logger.error("Failed to queue message for thread %s", thread_id)
     else:
         logger.info("Creating LangGraph run for thread %s", thread_id)
         langgraph_client = get_client(url=LANGGRAPH_URL)
-        run = await langgraph_client.runs.create(
+        await langgraph_client.runs.create(
             thread_id,
             "agent",
             input={"messages": [{"role": "user", "content": content_blocks}]},
@@ -689,7 +689,7 @@ async def process_linear_issue(  # noqa: PLR0912, PLR0915
             if_not_exists="create",
         )
         logger.info("LangGraph run created successfully for thread %s", thread_id)
-        await post_linear_trace_comment(issue_id, run["run_id"], triggering_comment_id)
+        await post_linear_trace_comment(issue_id, thread_id, triggering_comment_id)
 
 
 async def process_slack_mention(event_data: dict[str, Any], repo_config: dict[str, str]) -> None:
@@ -834,7 +834,7 @@ async def process_slack_mention(event_data: dict[str, Any], repo_config: dict[st
             logger.error("Failed to queue Slack message for thread %s", thread_id)
         return
 
-    run = await langgraph_client.runs.create(
+    await langgraph_client.runs.create(
         thread_id,
         "agent",
         input={"messages": [{"role": "user", "content": content_blocks}]},
@@ -842,7 +842,7 @@ async def process_slack_mention(event_data: dict[str, Any], repo_config: dict[st
         if_not_exists="create",
         multitask_strategy="interrupt",
     )
-    await post_slack_trace_reply(channel_id, thread_ts, run["run_id"])
+    await post_slack_trace_reply(channel_id, thread_ts, thread_id)
 
 
 def verify_linear_signature(body: bytes, signature: str, secret: str) -> bool: