/tools · 7IT Guard Pro · Custom sensors · Catalog

The custom sensor catalog

Every sensor planned for Guard Pro: what it catches, how it connects to your app, and where you set the limit. Below the tables: the probe endpoint, the ping address and the MCP tools, at the level of principles.

Coming to Guard Pro

123sensors

6categories

4ways to connect

How custom sensors work Guard Pro Plans

The catalog

Filter by category or by how it connects.

X A limit you set. Guard suggests it from your business's own history; you approve or change it.

Pull Guard checks your app Ping Your app pings Guard Probe Signed probe in your app Provider Read-only provider connection

Part of the Guard Pro watch Already among the checks Guard Pro runs on every watched app.

Online store

22 sensors

The checks a store owner wishes they had the week the checkout broke quietly.

Online store: sensors, what each catches, how it connects and the limit you set
Sensor	What it catches	How it connects	Your limit
Last order older than X hours	The checkout broke quietly	Probe	X you set
Checkout page loads and shows the pay button	A broken checkout	Pull	No limit to set
Add to cart works (a flow of a few steps)	A cart that does not update	Pull	No limit to set
Failed payments above X% in an hour	A problem with card processing	Providere.g. Stripe	X you set
Payment webhook not delivered	Orders that are never marked as paid	Providere.g. Stripe	No limit to set
Payments and orders differ by more than X	Lost orders	Probe	X you set
Best seller out of stock or below X units	Sales that stop	Probe	X you set
A product price changed by more than X%	A mistake or a break-in	Probe	X you set
A coupon used abnormally (over X uses an hour)	A coupon code that leaked	Probe	X you set
Order confirmation email sent	Customers who get no confirmation	Ping	No limit to set
Shipping cost is calculated	A shipping calculator that went down	Pull	No limit to set
Store search returns results	Broken search	Pull	No limit to set
Product images load	Broken images after a storage change	Pull	No limit to set
Inventory sync ran in the last X hours	Stock levels out of date	Ping	X you set
Orders not shipped within X days	Fulfillment running late	Probe	X you set
Refunds or cancellations above X%	A product problem or fraud	Providere.g. Stripe	X you set
New payment disputes	Risk to your payment account	Providere.g. Stripe	No limit to set
Price on the page differs from the price at checkout	A pricing fault	Pull	No limit to set
Product page slower than X seconds	Shoppers who leave	Pull	X you set
Daily order value X% below normal	A drop in sales	Probe	X you set
Abandoned carts above X%	A checkout that drives buyers away	Probe	X you set
Contact form submits	Messages that never arrive	Pull	No limit to set

Suspicious silence

21 sensors

The strongest category for a founder. Most expensive failures do not look like an error; they look like nothing happening. Each sensor alerts when something that should happen did not happen within X hours or days.

Suspicious silence: sensors, what each catches, how it connects and the limit you set
Sensor	What it catches	How it connects	Your limit
No new order within X	A broken checkout or payment	Probe	X you set
No new sign-up within X	A broken sign-up, or a verification email that never arrives	Probe	X you set
No successful sign-in within X	Broken sign-in	Probe	X you set
No successful payment within X	Card processing that got stuck	ProviderProbe	X you set
No subscription renewal within X	Recurring charges that fail	Providere.g. Stripe	X you set
No email sent by the system within X	The email provider blocked or suspended the account	Ping	X you set
No SMS or WhatsApp message within X	The messaging provider stopped	Ping	X you set
No contact form lead within X	A broken form	Probe	X you set
No user file upload within X	File storage full or blocked	Probe	X you set
No backup run within X	Backups that stopped	Ping	X you set
No sync from an outside system within X	An expired key or an API that changed	Ping	X you set
No hourly or daily scheduled job within X	A scheduler that was switched off	Ping	X you set
No content update (post, product, page) within X	A content system that is stuck	Probe	X you set
No call to the app's AI feature within X	The AI feature failing quietly	Probe	X you set
No analytics event from the site within X	Tracking code removed in a deploy	Ping	X you set
No home page visit within X	The site not reachable for real users	Ping	X you set
No job completed in the queue within X	A stuck queue	Probe	X you set
No invoice issued within X	An invoicing system that is stuck	Ping	X you set
No daily report sent to the admin within X	Reports that stopped	Ping	X you set
No new deploy within X (for projects that ship daily)	A deploy pipeline that is stuck	Pulldeploy fingerprint	X you set
Not even one active user within X	An app that is empty in practice	Probe	X you set

Databases and data

20 sensors

Checked from inside your app, with the connection it already has. 7IT never receives a database password.

Databases and data: sensors, what each catches, how it connects and the limit you set
Sensor	What it catches	How it connects	Your limit
Database answers within X ms	An outage or slowness	Probe	X you set
Open connections above X% of the limit	"Too many connections" on the way	Probe	X you set
Database size above X% of the plan	A switch to read-only mode	ProbeProvider	X you set
A table growing abnormally fast	A bug that duplicates rows, or spam	Probe	No limit to set
A table suddenly emptied	Accidental deletion or a break-in	Probe	No limit to set
A known query slower than X	An index that is missing or was dropped	Probe	X you set
Last backup older than X hours	Backups that stopped	PingProvider	X you set
The last tested restore passed	A backup you cannot restore from	Ping	No limit to set
Orphan records (an order with no customer) above X	Data that broke	Probe	X you set
A public table without row level security	Data open to everyone	Providere.g. Supabase	No limit to set
The data provider flags a new security advisory	A risky setting	Providere.g. Supabase	No limit to set
The project is close to pausing for inactivity	A database that falls asleep	PullProvider	No limit to set
Query errors above X an hour	Code that broke against the database	Ping	X you set
Locks waiting more than X seconds	A lock that freezes the app	Probe	X you set
The cache (Redis) answers	Cache down	Probe	No limit to set
Cache memory above X%	Data pushed out of the cache	Probe	X you set
File storage above X% of the plan	Uploads that are about to fail	Provider	X you set
A storage bucket turned public	Users' files leaking	Pullon an app you own	No limit to set
A migration that did not complete	A deploy stuck halfway	Probe	No limit to set
Replica lag above X seconds	Users shown stale data	Probe	X you set

Background jobs and integrations

20 sensors

The work nobody sees until it stops: scheduled jobs, queues, webhooks and the outside services your app calls.

Background jobs and integrations: sensors, what each catches, how it connects and the limit you set
Sensor	What it catches	How it connects	Your limit
A scheduled job ran on time	A cron job that was switched off	Ping	No limit to set
A job started and did not finish within X	A stuck job	Pingstart and success pings	X you set
A job failed (exit code)	An error during the run	Pingfail ping	No limit to set
A job took longer than X	Load that keeps growing	Ping	X you set
Queue above X jobs	Workers that cannot keep up	Probe	X you set
The oldest job has waited more than X	A stuck queue	Probe	X you set
Jobs that failed for good (dead letter)	Work that was lost	Probe	No limit to set
Incoming webhooks failed above X	A provider that stopped sending	Ping	X you set
An outside API key works	A key that expired or was revoked	Probe	No limit to set
A key or token expires within X days	A failure you can see coming	Probe	X you set
The email provider accepts requests	Emails that are not going out	Probe	No limit to set
Bounced emails above X%	Getting blocked on the way to inboxes	ProviderPing	X you set
The SMS provider answers	Messages that are not sent	Probe	No limit to set
An outside rate limit was exceeded	A temporary block that breaks a feature	Ping	No limit to set
The CRM or spreadsheet sync ran	Leads that never arrive	Ping	No limit to set
A customer export or report was produced	A process that failed	Ping	No limit to set
Image or video processing finished	A heavy process that is stuck	Ping	No limit to set
Jobs that ran twice (duplicates)	Double emails or double charges	Ping	No limit to set
The background worker is connected and alive	A worker that crashed	Ping	No limit to set
GitHub Actions run succeeded	A deploy or tests that failed	ProviderGitHub	No limit to set

SaaS and users

20 sensors

Sign-in, subscriptions and the one action your product exists for, watched the way a user meets them.

SaaS and users: sensors, what each catches, how it connects and the limit you set
Sensor	What it catches	How it connects	Your limit
The sign-in flow works (test user)	Sign-in broken after a change	Pulla flow of a few steps	No limit to set
Failed sign-ins above X% an hour	A sign-in fault, or break-in attempts	Probe	X you set
A burst of sign-in attempts from one source	Password guessing	Probe	No limit to set
Suspicious sign-ups above X an hour	Bots and spam	Probe	X you set
The verification email arrives within X minutes	Users stuck at sign-up	Ping	X you set
The password reset link works	Users locked out	Pull	No limit to set
Sign-in with Google or GitHub works	A sign-in provider that broke	Pull	No limit to set
Active subscriptions dropped X% in a day	Cancellations or failed charges	Providere.g. Stripe	X you set
Failed recurring charges above X	Revenue being lost	Providere.g. Stripe	X you set
A paying user did not get access	Permissions that do not update	Probe	No limit to set
A cancelled user still has access	Service given away after cancelling	Probe	No limit to set
Daily active users X% below normal	A bug that drives users away	Probe	X you set
The product's core action succeeds (save, send, create)	The main feature broke	PullProbe	No limit to set
Inviting a user to a team works	Growth that is blocked	Pull	No limit to set
A user's data export completes	Privacy requests left unhandled	Ping	No limit to set
Account deletion requests waiting more than X days	Legal exposure	Probe	X you set
Users go past their plan's limits	Limits that are not enforced	Probe	No limit to set
User notifications (push, email) were sent	A notification system that is stuck	Ping	No limit to set
Main API response time above X	Slowness users can feel	Pull	X you set
A burst of errors on users' screens above X a minute	Crashes on the user's side	Pingfail ping	X you set

AI features

20 sensors

Most apps built with AI also use AI. Here the risk is both money and quality.

AI features: sensors, what each catches, how it connects and the limit you set
Sensor	What it catches	How it connects	Your limit
The AI feature answers a test question correctly	A broken feature	Probe	No limit to set
Daily AI spend above X	A bill that blows up	ProviderProbe	X you set
One user consumes more than X% of the spend	Abuse	Probe	X you set
AI provider rate-limit errors above X	Hitting the provider's rate limit	Ping	X you set
AI provider credit about to run out	A feature that stops tomorrow	Provider	No limit to set
Average AI response time above X seconds	Users kept waiting	Ping	X you set
Empty or cut-off answers above X%	Quality that dropped	Ping	X you set
A retired model still in use	A break you can see coming	Probe	No limit to set
AI endpoint open without sign-in Part of the Guard Pro watch	Usage billed to you	Pull	No limit to set
AI key in the code browsers receive Part of the Guard Pro watch	A key that leaked	Pull	No limit to set
AI provider outage Part of the Guard Pro watch	A feature failing through no fault of yours	Providerprovider status page	No limit to set
AI requests above X an hour	A usage spike or an attack	Ping	X you set
Content filter blocks above X	Misuse, or a filter set too strict	Ping	X you set
Document search (vector) returns results	An index that was deleted or is empty	Probe	No limit to set
Documents waiting for processing above X	Embedding work that is stuck	Probe	X you set
Average cost per AI chat up X%	A prompt that grew after an update	Ping	X you set
An agent looping beyond X steps	Cost with no ceiling	Ping	X you set
An MCP server the app uses answers	An outside tool that is down	Provider7Maps data	No limit to set
The system prompt changed in a deploy	An unintended change in behavior	Probefingerprint only	No limit to set
Negative user feedback (thumbs down) above X%	Quality that dropped	Ping	X you set

By connection method

How the library connects.

Sensors per category and connection method. A sensor that can use two methods counts in both.

Number of sensors by category and connection method
Category	Pull	Ping	Probe	Provider	Sensors
Online store	8	2	8	4	22
Suspicious silence	1	9	10	2	21
Databases and data	2	3	12	6	20
Background jobs and integrations	0	12	7	2	20
SaaS and users	6	4	9	2	20
AI features	2	8	7	4	20
All	19	38	53	20	123

Pull Guard checks your app

Guard calls an address in your app on a schedule and checks the answer: a page, an API response, a word that must appear, a flow of a few steps.

Good for: Pages, APIs, sign-in and checkout flows, subdomains

Ping Your app pings Guard

Your job or app calls its own private ping address when something happens. A ping that does not arrive on time is the alert.

Good for: Cron jobs, backups, syncs, queues, emails the system sends

Probe Signed probe in your app

A small endpoint your AI adds to your app. Guard asks it with a signed request; it runs read-only checks inside your app and answers with a signed OK or not OK plus numbers.

Good for: Databases, internal services, keys to outside providers, business numbers

Provider Read-only provider connection

A one-click, read-only connection to a provider you already use, such as your payments, database or code host. Guard reads health and numbers; it cannot change anything.

Good for: Payments, database platforms, code hosting, AI providers

The probe endpoint

A signed check that runs inside your app.

One address in your app, such as /api/guard-probe, added by your AI from the probe kit for your stack: Next.js, Supabase Edge Functions, Express or Python.

Signed requests only. It answers only a request signed (HMAC) with your app's own key, refuses anything unsigned, altered or stale, and signs its answer the same way. You can replace the key in one click.
Read-only checks you approved. It uses the connection your app already has and runs only read-only checks you confirmed. The queries live in your code, not with 7IT.
Status and numbers, never rows. The answer holds a status and numbers. Never rows, never user data, never secrets. Its size and shape are limited.
Rate-limited. It limits how often it can be asked.
An open format. The answer follows the shape of the IETF draft "Health Check Response Format for HTTP APIs": an overall status of pass, warn or fail, and checks named component:measurement with an observed value and unit.

An answer, with sample values

HTTP/1.1 200 OK
Content-Type: application/health+json

{
  "status": "pass",
  "checks": {
    "database:responseTime": [
      { "observedValue": 41, "observedUnit": "ms", "status": "pass" }
    ],
    "orders:lastCreatedAge": [
      { "observedValue": 37, "observedUnit": "min", "status": "pass" }
    ],
    "jobs:queueDepth": [
      { "observedValue": 3, "observedUnit": "jobs", "status": "pass" }
    ]
  }
}

The ping address

For jobs that should report in.

Each ping sensor has its own private address that cannot be guessed. A ping that does not arrive on time is the alert.

<ping-url>: Success: the job ran.
<ping-url>/start: The job started. Guard measures how long it runs and notices a job that started and never finished within your limit.
<ping-url>/fail: The job failed.
<ping-url>/<exit code>: The job's exit code: 0 is success, anything else is a failure.
Grace: How long after the expected time Guard waits before it alerts. You set it; Guard suggests it from the job's own history.

In a scheduled job

# the job started
curl -fsS -m 10 <ping-url>/start

# the job ran: report its exit code (0 is success)
./nightly-email.sh
curl -fsS -m 10 <ping-url>/<exit code>

The address can be replaced in one click. Incoming pings are rate-limited.

MCP tools

The tools your AI uses.

New tools on the 7IT Guard MCP server, also available as a regular API with your 7IT key.

propose_sensors: Takes what you want watched, in words, and the app. Returns a proposed list of sensors in a fixed shape. Saves nothing.
get_probe_snippet: Returns a short probe endpoint for your stack (Next.js, Supabase Edge Functions, Express, Python) and the app's own signing key, for your AI to add to the code.
add_sensor: Registers one sensor, only after you confirm it in the chat. Marked as a tool that changes state.
test_sensor: Runs the sensor once and shows what it will report when it watches.
list_sensors, sensor_status: What is watched, and how each sensor stands right now.
pause_sensor, remove_sensor: Pause or remove a sensor.

Rules that always hold

Your yes, every time. Your AI never registers or changes a sensor without your explicit confirmation in the chat.
Paused until proven. A new sensor starts paused and turns on when its first check passes.
Only your app. A sensor aimed outside an app whose ownership was proven, and its subdomains, is refused. Outside APIs, such as your payment provider, are checked through your own probe, not directly.
No secrets in settings. A sensor setting that looks like a key or a password is refused when it is registered.
Edit without AI. Pausing, renaming and removing a sensor also work from a simple screen in the control room. Adding one always goes through your AI, because it adds the code to your app.

This page describes what sensors do and how they connect. How Guard decides when to alert stays internal.

Coming to Guard Pro

Custom sensors open with Guard Pro.

Part of Guard Pro and Pro + personal guidance. Prices are published when it opens.

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