Networks are unreliable. Weve all experienced trouble connecting to Wi-Fi, or had a phone call drop on us abruptly.

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To overcome this sort of inherently unreliable environment, its important to design APIs and clients that will be robust in the event of failure, and will predictably bring a complex integration to a consistent state despite them. Lets take a look at a few ways to do that.

Source: Designing robust and predictable APIs with idempotency

Basically, they add an Idempotency-Key header to allow repeatable requests.

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