Amazon wants a key to your house. I did it. I regretted it.

For an ask this big (total access to your home, after all), Amazon needs to make Key better. Photo / Amazon YouTube

I gave Amazon.com a key to go into my house and drop off packages when I'm not around. After two weeks, it turns out letting strangers in has been the least-troubling part of the experience.

Once Amazon owned my door, I was the one locked into an all-Amazon world.

When Amazon first floated the idea of Amazon Key, an Internet-connected lock it can access, people had two responses.

1) This is creepy.

2) I kind of want this, so my packages don't get stolen.

But make no mistake, the $250 Amazon Key isn't just about stopping thieves. It's the most aggressive effort I've seen from a tech giant to connect your home to the Internet in a way that puts itself right at the centre.

Amazon chief executive Jeff Bezos owns The Washington Post, but I review all tech with the same critical eye. So I put an Amazon-compatible smart lock on my door (installation was included) and hooked up its companion Cloud Cam nearby to record who comes and goes. Then I ordered enough Amazon packages to earn overtime for Santa's elves.

The good news is nobody ran off with my boxes - or burgled my house.

The bad news is Amazon missed four of my in-home deliveries and charged me (on top of a Prime membership) for gear that occasionally jammed and makes it awkward to share my own door with people, apps, services - and, of course, retailers - other than Amazon.

"Amazon Key has had a positive reception from customers since its launch last month," Amazon spokeswoman Kristen Kish said.

"There have been situations where we haven't gotten it right with a delivery and we use these situations to continue making improvements to the service."

Big tech companies love building walled gardens, in ham-handed attempts to keep customers loyal. But for an ask this big (total access to your home, after all), Amazon needs to make Key better.

Smart locks get a purpose

Amazon's path to home domination requires persuading Americans to connect appliances and everyday things to the Internet - thermostats, lights, even water filters. With the Echo speaker and Alexa talking assistant, it's had more luck than most companies at getting us interested.

What Amazon gets right is that the so-called smart home has to solve real problems. Smart locks have been around for years, but Amazon Key finds a real use for them: stopping package theft.

Amazon smartly paired the lock with its security Cloud Cam. Having a camera - which only you can watch, and which must be powered up for the door to unlock - makes this a little less terrifying. (If the power goes out, you can always open the door with an old-fashioned key.)

When you use Amazon Key, you get a phone alert with a window when a delivery might occur. If no one is home, the delivery person taps an app that grants one-time access to unlock your door, places the package inside, then relocks the door. (They don't recommend Key if you have a pet, and won't come in if they hear barking.) The moment the door unlocks, the Cloud Cam starts recording - and sends you a live stream of the whole thing. It's a surreal 15 seconds.

Even if your family runs on Prime shipping, this scenario would likely test your faith in Amazon. There are certainly less-invasive ways to keep packages safe, like lockboxes or shipping to the office. The company promises deliveries are only made by Amazon employees it thinks are trustworthy. It also says that it will "correct the problem" if your property gets damaged. (In the fine print, you also agree to arbitration, rather than a lawsuit, if something goes really wrong.)

Amazon's drivers earned high marks for discretion. Most of them opened the door just enough to slide in a package. None of them stopped to use the toilet. None of them took a cookie - not even when I set some by the door with a card.

The Amazon workers are no doubt aware they're under digital surveillance. Amazon's systems monitor their whereabouts before they can unlock the door, and when they lock it again.

If only it worked

Worry about a creepy driver turned out to just be the beginning of Amazon Key's problems.

The other reason smart home tech has been a tough slog for Silicon Valley is that houses come in so many shapes and ages. And there's a lot at stake if tech fails where you live.

My Amazon Key setup was finicky, even though Amazon sent someone to help. My installer was friendly, but found a problem with my decades-old door he wasn't authorized to fix - the spot where the deadbolt went into the frame slightly misaligned. I paid a locksmith $100 for a new strike plate, which was Amazon's recommendation.

That wasn't enough. From time to time, my Kwikset Convert lock makes a screech that would alarm a hyena, and flashes a warning in the Key app about jamming.

Even worse, that happened during an Amazon delivery. Fortunately, the driver kept trying until the door actually locked. Amazon said it thinks my lock is not properly installed. I also might have had a better experience with one of the two other compatible smart locks, whose designs are bulkier.

Then I heard Amazon Key got hacked. Researchers found a way a rogue delivery person could cause the security camera to freeze and then potentially lurk in your house. Amazon said customers weren't really at risk, but pushed a software update to provide quicker notifications if the camera goes offline during delivery.

The biggest head scratcher: Of eight in-home deliveries, Amazon missed its original delivery window on four of them. It sent some inaccurate alerts about when packages might arrive, which is especially unnerving when drivers might be entering your house. (The packages all arrived eventually, a day or more late.) This is a record-breaking online shopping season, but this is the part of the business I expect Amazon to get right.

Who owns your door?

When you add Amazon Key to your door, something more sneaky also happens: Amazon takes over.

You can leave your keys at home and unlock your door with the Amazon Key app - but it's really built for Amazon deliveries. To share online access with family and friends, you have to give them a special code to SMS (yes, text) to unlock the door.

The Key-compatible locks are made by Yale and Kwikset, yet don't work with those brands' own apps. They also can't connect with a home-security system or smart-home gadgets that work with Apple and Google software.

When you add Amazon Key to your door, something more sneaky also happens: Amazon takes over. Photo / Amazon

And, of course, the lock can't be accessed by businesses other than Amazon. No Walmart, no UPS, no local dog-walking company.

Keeping tight control over Key might help Amazon guarantee security or a better experience. "Our focus with smart home is on making things simpler for customers - things like providing easy control of connected devices with your voice using Alexa, simplifying tasks like reordering household goods and receiving packages," the Amazon spokeswoman said.

But Amazon is barely hiding its goal: It wants to be the operating system for your home. Amazon says Key will eventually work with dog walkers, maids and other service workers who bill through its marketplace. An Amazon home security service and grocery delivery from Whole Foods can't be far off. (Walmart has announced plans to test delivering groceries straight to the refrigerator with a smart lock maker called August.)

Amazon said it doesn't have access to data about when you lock your door or the video feed from the Cloud Cam - both good things. But surely its data team is also crunching the numbers on how Key changes your consumer behavior, especially whether you are buying more stuff from Amazon.

What's so bad about living in an all-Amazon house? The company doesn't always have the best prices, or act in ways that benefit consumers. For example, it's currently in a spat with Google, whose smart-home products like Chromecast and Google Home are not carried by Amazon - and who retaliated by blocking access to its YouTube apps on some Amazon products. (Grow up, you two!)

Amazon Key did give me some peace of mind about delivery theft. But the trade-off is giving more power over your life to a company that probably already has too much.