Get started

LangSmith alert notifications on your phone.

Get a push notification when a LangSmith project alert on errors, latency, cost or feedback score crosses its threshold.

Install in Studio See the setup
alertAIMonitoring
How it works

Three steps to your first push

STEP 01

Install the recipe

One click in Studio gives you a personal webhook URL.

STEP 02

Paste your URL into LangSmith

Add it as a webhook for Alert.

STEP 03

Get a push on your phone

With the text, sound and buttons from the recipe.

Setup

How to set up the LangSmith alert webhook

  1. Click Install in Studio and sign in. The recipe is added to your account and you get a personal webhook URL.
  2. Follow the setup notes below: Alert is configured in a different part of LangSmith than the other recipes.
  3. Paste your webhook URL (plus any query parameters from the notes) as the webhook URL and save.https://••••••••/•••••••• your personal URL, shown after install
  4. In your tracing project, click the **Alerts** icon (top right) → **+ Alert**, pick the metric and threshold, and under **Notification Settings** choose **Webhook**. Paste the URL above.
  5. Leave the **request body template** empty (or `{}`): LangSmith adds the alert details itself, and doesn't fill in `{placeholders}` in the template.
  6. Use **Send Test Alert** to check it. LangSmith doesn't sign alert webhooks, so keep your endpoint URL private.
The code

What runs when the webhook arrives

Studio calls handleRequest(request) with the incoming webhook and sends the message it returns. It's yours after install; change anything.

transform.js
1// LangSmith → alert
2// Fires when a LangSmith project alert (errors, latency, cost, feedback score, run count)
3// crosses its threshold and notifies a Webhook channel.
4// Docs: https://docs.langchain.com/langsmith/alerts
5
6// alert_rule_attribute → how to describe the metric.
7const METRICS = {
8 error_count: { label: "Errors", emoji: "❌" },
9 feedback_score: { label: "Feedback score", emoji: "👎" },
10 latency: { label: "Latency", emoji: "🐢" },
11 cost: { label: "Cost", emoji: "💸" },
12}
13
14// Round to at most two decimals without trailing zeros: 0.1234 → "0.12", 12 → "12".
15function num(value) {
16 const n = Number(value)
17 return Number.isFinite(n) ? String(Math.round(n * 100) / 100) : null
18}
19
20// Only link to real http(s) URLs.
21function link(url, cta) {
22 return typeof url === "string" && /^https?:\/\//.test(url) ? [{ cta, url }] : []
23}
24
25function handleRequest(request) {
26 const body = request.body || {}
27
28 // Guard: only LangSmith alert payloads, so anything else on this integration stays quiet.
29 if (!body.alert_rule_id || !body.alert_rule_name) {
30 console.log("Not a LangSmith alert payload — skipping")
31 return null
32 }
33
34 const metric = Object.prototype.hasOwnProperty.call(METRICS, body.alert_rule_attribute)
35 ? METRICS[body.alert_rule_attribute]
36 : { label: "Metric", emoji: "🚨" }
37 const value = num(body.triggered_metric_value)
38 const threshold = num(body.triggered_threshold)
39 const reading = value
40 ? `${metric.label} ${value}` + (threshold ? ` (threshold ${threshold})` : "")
41 : null
42 const where = body.project_name ? ` in ${body.project_name}` : ""
43
44 return {
45 title: `${metric.emoji} ${body.alert_rule_name}`,
46 message: (reading ?? "Alert threshold crossed") + where,
47 topic: "LangSmith",
48 priority: 1, // High — an alert you set up yourself just crossed its line
49 buttons: [...link(body.runs_url, "View runs"), ...link(body.alert_rule_url, "View alert")],
50 }
51}
Payload

The LangSmith alert webhook

This is what LangSmith sends to your URL for alert. It is a sample, trimmed to the fields recipes use.

alert · sample.json
1{
2 "runs_url": "https://smith.langchain.com/o/2ebda79f/projects/p/6a3be6a2?filter=eq(is_root%2C%20true)%2Ceq(error%2C%20true)",
3 "timestamp": "2026-09-29T09:15:00Z",
4 "project_name": "support-bot",
5 "alert_rule_id": "5e2f4c1a-7b3d-4e8f-9a0b-1c2d3e4f5a6b",
6 "alert_rule_url": "https://smith.langchain.com/o/2ebda79f/projects/p/6a3be6a2?alertRule=5e2f4c1a",
7 "workspace_name": "Acme",
8 "alert_rule_name": "Error spike",
9 "alert_rule_type": "threshold",
10 "triggered_threshold": 10,
11 "alert_rule_attribute": "error_count",
12 "alert_rule_description": "",
13 "triggered_metric_value": 14
14}
FAQ

LangSmith alert notifications: questions

Does this work on iPhone and Android?

Yes. Install the JustPush app from the App Store or Google Play and sign in. Every phone signed in to your account gets the notification.

Do I need to write code?

No. Install the recipe in Studio, paste your webhook URL into LangSmith and you are done. The code is there if you want to change the text, the sound or the buttons.

Can I change what the notification says?

Yes. After install the recipe's code is yours. Edit it in Studio and test it against the sample payload before you save.

What does it cost?

JustPush is free for 30 days. After that it's $19.99 a year, or $39.99 once. There is no extra charge for recipes.

More recipes

More from LangSmith

LangSmith

Agent run finished

Get a push notification when a LangGraph agent run finishes, fails or times out, with how long it took and the agent's final answer.

run
LangSmith

Automation rule

Get a push notification when runs match a LangSmith automation rule, such as runs that error or get negative feedback.

automationButtons

All 3 LangSmith recipes

Monitoring

More monitoring recipes

Arize AX

Monitor alert

Get a push notification when an Arize AX monitor triggers, clears, or stops receiving data.

monitor.triggeredButtons
Better Stack

Incident

Get a Highest-priority push notification when a Better Stack incident starts, and quiet ones when it's acknowledged or resolved, plus incident comments.

incident_changeButtons
Better Stack

On-call change

Get a push notification when the on-call person changes on a Better Stack on-call calendar.

on_call_change

All monitoring recipes

Ready when you are

LangSmith on your phone in two minutes.

Install the recipe, paste one URL, done. Free for 30 days, no credit card required.

Install in Studio Download for iOS Download for Android