feat: send LangSmith trace URL on run trigger from Slack and Linear (#1057)

* feat: send LangSmith trace URL on run trigger from Slack and Linear

* fix: check LANGSMITH_PROJECT before LANGSMITH_PROJECT_PROD for project name lookup

* fix: pass LangSmith API key explicitly to Client and remove global variable

* Update agent/utils/langsmith.py

Co-authored-by: Brace Sproul <braceasproul@gmail.com>

* refactor: move trace notification helpers out of webapp and use env vars for LangSmith URL base

* docs: add LangSmith tenant and project ID env vars to installation guide

* fix: remove unused comment_on_linear_issue import from webapp

* nit: remove lru_cache, make get_langsmith_trace_url sync, and move langsmith import to top level

* Update INSTALLATION.md

Co-authored-by: Brace Sproul <braceasproul@gmail.com>

* Update INSTALLATION.md

Co-authored-by: Brace Sproul <braceasproul@gmail.com>

* Update INSTALLATION.md

Co-authored-by: Brace Sproul <braceasproul@gmail.com>

---------

Co-authored-by: Brace Sproul <braceasproul@gmail.com>

INSTALLATION.md

@@ -1,3 +1,4 @@
+
 # Installation Guide
 
 This guide walks you through setting up Open SWE end-to-end: local development, GitHub App creation, LangSmith configuration, webhooks, and production deployment.
@@ -105,11 +106,13 @@ Open SWE uses [LangSmith](https://smith.langchain.com/) for:
 - **Tracing**: all agent runs are logged for debugging and observability
 - **Sandboxes**: each task runs in an isolated LangSmith cloud sandbox
 
-### 4a. Get your API key
+### 4a. Get your API key, project and tenant IDs
 
 1. Create a [LangSmith account](https://smith.langchain.com/) if you don't have one
 2. Go to **Settings → API Keys → Create API Key**
 3. Save it as `LANGSMITH_API_KEY_PROD`
+4. Get your **Tenant ID**: Visit LangSmith, login, then copy the UUID in the URL. Example: if your URL is `https://smith.langchain.com/o/72184268-01ea-4d29-98cc-6cfcf0f2abb0/agents/chat` -> the tenant ID would be `72184268-01ea-4d29-98cc-6cfcf0f2abb0`. Save it as `LANGSMITH_TENANT_ID_PROD`.
+5. Get your **Project ID**: open your tracing project in LangSmith, then click on the **ID** button in the top left, directly next to the project name. Save it as `LANGSMITH_TRACING_PROJECT_ID_PROD`
 
 ### 4b. Configure GitHub OAuth (optional but recommended)
 
@@ -300,6 +303,9 @@ Create a `.env` file in the project root. Below is the full list — only fill i
 LANGSMITH_API_KEY_PROD=""              # From step 4a
 LANGCHAIN_TRACING_V2="true"
 LANGCHAIN_PROJECT=""                   # LangSmith project name for traces
+LANGSMITH_TENANT_ID_PROD=""           
+LANGSMITH_TRACING_PROJECT_ID_PROD=""  
+LANGSMITH_URL_PROD="https://smith.langchain.com"                 
 
 # === LLM ===
 ANTHROPIC_API_KEY=""                   # Anthropic API key (default provider)

agent/utils/langsmith.py

@@ -0,0 +1,30 @@
+"""LangSmith trace URL utilities."""
+
+from __future__ import annotations
+
+import logging
+import os
+
+logger = logging.getLogger(__name__)
+
+
+def _compose_langsmith_url_base() -> str:
+    """Build the LangSmith URL base from environment variables."""
+    host_url = os.environ.get("LANGSMITH_URL_PROD", "https://smith.langchain.com")
+    tenant_id = os.environ.get("LANGSMITH_TENANT_ID_PROD")
+    project_id = os.environ.get("LANGSMITH_TRACING_PROJECT_ID_PROD")
+    if not tenant_id or not project_id:
+        raise ValueError(
+            "LANGSMITH_TENANT_ID_PROD and LANGSMITH_TRACING_PROJECT_ID_PROD must be set"
+        )
+    return f"{host_url}/o/{tenant_id}/projects/p/{project_id}/r"
+
+
+def get_langsmith_trace_url(run_id: str) -> str | None:
+    """Build the LangSmith trace URL for a given run ID."""
+    try:
+        url_base = _compose_langsmith_url_base()
+        return f"{url_base}/{run_id}?poll=true"
+    except Exception:  # noqa: BLE001
+        logger.warning("Failed to build LangSmith trace URL for run %s", run_id, exc_info=True)
+        return None

agent/utils/linear.py

@@ -7,17 +7,22 @@ import os
 
 import httpx
 
+from agent.utils.langsmith import get_langsmith_trace_url
+
 logger = logging.getLogger(__name__)
 
 LINEAR_API_KEY = os.environ.get("LINEAR_API_KEY", "")
 
 
-async def comment_on_linear_issue(issue_id: str, comment_body: str) -> bool:
+async def comment_on_linear_issue(
-    """Add a comment to a Linear issue.
+    issue_id: str, comment_body: str, parent_id: str | None = None
+) -> bool:
+    """Add a comment to a Linear issue, optionally as a reply to a specific comment.
 
     Args:
         issue_id: The Linear issue ID
         comment_body: The comment text
+        parent_id: Optional comment ID to reply to
 
     Returns:
         True if successful, False otherwise
@@ -28,8 +33,8 @@ async def comment_on_linear_issue(issue_id: str, comment_body: str) -> bool:
     url = "https://api.linear.app/graphql"
 
     mutation = """
-    mutation CommentCreate($issueId: String!, $body: String!) {
+    mutation CommentCreate($issueId: String!, $body: String!, $parentId: String) {
-        commentCreate(input: { issueId: $issueId, body: $body }) {
+        commentCreate(input: { issueId: $issueId, body: $body, parentId: $parentId }) {
             success
             comment {
                 id
@@ -48,7 +53,11 @@ async def comment_on_linear_issue(issue_id: str, comment_body: str) -> bool:
                 },
                 json={
                     "query": mutation,
-                    "variables": {"issueId": issue_id, "body": comment_body},
+                    "variables": {
+                        "issueId": issue_id,
+                        "body": comment_body,
+                        "parentId": parent_id,
+                    },
                 },
             )
             response.raise_for_status()
@@ -56,3 +65,14 @@ async def comment_on_linear_issue(issue_id: str, comment_body: str) -> bool:
             return bool(result.get("data", {}).get("commentCreate", {}).get("success"))
         except Exception:  # noqa: BLE001
             return False
+
+
+async def post_linear_trace_comment(issue_id: str, run_id: str, triggering_comment_id: str) -> None:
+    """Post a trace URL comment on a Linear issue."""
+    trace_url = get_langsmith_trace_url(run_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,
+        )

agent/utils/slack.py

@@ -12,6 +12,8 @@ from typing import Any
 
 import httpx
 
+from agent.utils.langsmith import get_langsmith_trace_url
+
 logger = logging.getLogger(__name__)
 
 SLACK_API_BASE_URL = "https://slack.com/api"
@@ -355,3 +357,12 @@ async def fetch_slack_thread_messages(channel_id: str, thread_ts: str) -> list[d
 
     messages.sort(key=lambda item: _parse_ts(item.get("ts")))
     return messages
+
+
+async def post_slack_trace_reply(channel_id: str, thread_ts: str, run_id: str) -> None:
+    """Post a trace URL reply in a Slack thread."""
+    trace_url = get_langsmith_trace_url(run_id)
+    if trace_url:
+        await post_slack_thread_reply(
+            channel_id, thread_ts, f"Working on it! <{trace_url}|View trace>"
+        )

agent/webapp.py

@@ -36,6 +36,7 @@ from .utils.github_comments import (
 )
 from .utils.github_token import get_github_token_from_thread
 from .utils.github_user_email_map import GITHUB_USER_EMAIL_MAP
+from .utils.linear import post_linear_trace_comment
 from .utils.linear_team_repo_map import LINEAR_TEAM_TO_REPO
 from .utils.multimodal import dedupe_urls, extract_image_urls, fetch_image_block
 from .utils.slack import (
@@ -45,6 +46,7 @@ from .utils.slack import (
     get_slack_user_info,
     get_slack_user_names,
     post_slack_thread_reply,
+    post_slack_trace_reply,
     select_slack_context_messages,
     strip_bot_mention,
     verify_slack_signature,
@@ -680,12 +682,16 @@ async def process_linear_issue(  # noqa: PLR0912, PLR0915
 
         if queued:
             logger.info("Message queued for thread %s, will be processed by middleware", thread_id)
+            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)
         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)
-        await langgraph_client.runs.create(
+        run = await langgraph_client.runs.create(
             thread_id,
             "agent",
             input={"messages": [{"role": "user", "content": content_blocks}]},
@@ -693,6 +699,7 @@ 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)
 
 
 async def process_slack_mention(event_data: dict[str, Any], repo_config: dict[str, str]) -> None:
@@ -800,7 +807,7 @@ async def process_slack_mention(event_data: dict[str, Any], repo_config: dict[st
 
     langgraph_client = get_client(url=LANGGRAPH_URL)
     await _upsert_slack_thread_repo_metadata(thread_id, repo_config, langgraph_client)
-    await langgraph_client.runs.create(
+    run = await langgraph_client.runs.create(
         thread_id,
         "agent",
         input={"messages": [{"role": "user", "content": content_blocks}]},
@@ -808,6 +815,7 @@ 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"])
 
 
 def verify_linear_signature(body: bytes, signature: str, secret: str) -> bool: