In response Amazon did a lot to reduce price transparency. If you notice now most categories of items are constantly 'on sale' and even if camelcamelcamel picks up that fact, there are also 'coupons' available on-site for most amazon products that only alter the price under certain conditions and they're only applied at checkout.

This makes it difficult for a human being trying to buy things to compare the prices, let alone a series of scripts.

if memory serves camelcamelcamel gets their pricing data directly from amazon via a source they aren't allowed to disclose, and bloomberg has previously reported that amazon gives camel^3 the data they have; given that, i'm not too certain they're the cause of amazon's consistent reduction in transparency to consumers - a lot of it feels like cruft built into their marketplace allowing for bad actors to effectively play the marketplace

having personally built an internal tool that was much more aggressive than camelcamelcamel, I can say they're not doing anything special in terms of sources (or if they are, it's totally unnecessary)

Was thinking about building such tool, but I couldn't come up with an idea where to source the data other than scraping it. Was looking especially for big price drops.

Cammelx3 is great. I like Keepa as well, especially the chrome extension that embeds the chart on the Amazon page. It also seems to have a bit more functionality.

The Firefox extension of keepa does the same btw

There's also keepa.com.