Individuals are not paying API prices for coding. Everyone uses a subscription.

Anthropic does not allow you to use 3rd party harnesses -- you have to use Claude Code. Claude Code is an excellent harness, though.

If you want the freedom to move between harnesses you should use OpenAI or xAI

Subscriptions provide thousands of dollars' worth of tokens if measured at API prices. While the value was once absurd, it is now slightly lower but still much cheaper.

anthropic subscription does not allow 3rd party harnesses i believe