What does this equation mean?

$s_{\text{capability}}$ is the quantity anyone citing the score actually wants: the rate at which the policy would solve genuinely novel instances of this task class. $\Delta_{\text{leak}}$ is inflation from the environment itself disclosing the solution — through its history, its documentation, or a live network path to the answer. $\Delta_{\text{checker}}$ is inflation from a verifier that can be satisfied by something other than a correct solution — a weak test suite, a policy that exploits how success is graded rather than what it is graded on. $\Delta_{\text{fingerprint}}$ is a shift, in either direction, from the policy detecting that it is inside an evaluation and adjusting its behavior because of that detection alone, independent of the task. A single-turn benchmark has to worry about something close to $\Delta_{\text{leak}}$ alone. An agentic one has to worry about all three, and — this is the part that makes the topic worth its own article — the three interact, because a capable-enough policy can use the environment’s own tools to go looking for $\Delta_{\text{leak}}$ on purpose.