Fable 5 and the End of “All‑You‑Can‑Eat” AI

Yesterday, Anthropic released their latest AI model, Fable 5.

This new model is essentially the Mythos model that has been grabbing headlines because it is too dangerous to ship, adjusted to make it safe to put into all our hands. This comes little less than two weeks after Opus 4.8 arrived. According to the benchmarks it's moderately smarter than Opus, but for a significant uplift in cost.

Underneath this release headline though is something we should probably all be thinking about: Access to Fable 5 via Claude subscription has been time limited. After June 22, even users on Claude's Max or legacy seat-based Enterprise tiers will be billed per token.

Anthropic states, "when sufficient capacity allows us to do so—we aim to restore Fable 5 as a standard part of subscription plans", but should we expect that this will necessarily still be while Fable 5 is the latest and greatest model?

In the last couple of weeks we have seen the reality of token economics run into AI aspirations at high speed. GitHub Copilot moved over to usage-based billing. Microsoft released Scout, a new Frontier Copilot feature that requires a usage-based plan rather than drawing on Copilot entitlement. And now, Anthropic has set a timeline to remove an included high-end model from its subscription plans. The stated reason for this change in Claude shipping approach is capacity, but it aligns so clearly with the retreat we are seeing industry-wide on seat-based billing that it feels like it's probably not a coincidence.

What does this mean for you?

We might be reaching a point where experimenting with AI, at least when using the most capable models, is about to become far more expensive across most workloads. This does not impact the ultimate efficacy of AI in your processes, but it does affect the path to ROI.

We have gotten used to turning nuclear reactors to tasks that require a 9v battery. When there is no real penalty to using the latest Opus model for a task that could be done by Haiku, why spend time thinking about it? Microsoft's decision to default Copilot use to an "Auto" model choice is a smart one for managing capacity sustainably.

How are you thinking about the changing cost reality of AI for you or your business? Will the release of Fable 5 mark a step change in how we get access to frontier models, or do you expect to see it added back for subscription users rapidly?