---
title: "One Failed Health Check Is Not a Reason to Kill It"
canonical: https://dxdev.com/everyday-ai/one-failed-health-check-is-not-a-death-sentence/
datePublished: 2026-10-12
---
One missed 1-second probe was enough for our automation to kill and relaunch a busy but healthy signed-in browser.

The pool that manages that browser tested for a wedge with a single 1-second probe of `/json/version`. One miss went straight to kill and relaunch.

## How it turned up

We had an AI assistant work through a list of findings about our own automation. For this one it read the kill logic and saw that the wedge test was a single 1-second probe that led straight to a kill. It wrote 6 new tests first. They failed without the fix and passed with it.

## What the pool checks before it kills

The pass now skips the kill if any one of these holds:

- A patient 8-second re-probe gets an answer.
- A live CDP lease holder exists.
- A CDP success was recorded within the last 15 minutes.

A browser that stays silent is still repaired once the 15 minutes pass.

## A spin that wasn't there

The same list had a finding about a window agent that was supposedly spinning. The assistant could not reproduce it. The window agent is parked on purpose and not running, and `desk_live` used 0.00 CPU-seconds over a 60-second sample. The loop had been rewritten to be event-driven on 9/25, inside the window the finding covers. It found no proven spin path, so there was no fix. If it recurs, the next step is a `py-spy` dump.

## A hold that stays

Another finding was about the bridge holding messages while a session is busy. The assistant left it alone. The hold is deliberate, an existing test covers it, and the only real fix is risky. It triaged the finding with a proposal instead.

## One more fix in the same commit

`the CLI chrome launch` now spots Chrome running on the agent profile with no debug port and fails fast with rc 3. The message names the cause, an app shortcut such as the WhatsApp PWA, and the safe command, `the CLI chrome kill`, which refuses while a session holds the lease. I added 4 tests. The shortcut still shares the profile, so a separate profile for WhatsApp is the real fix.