Use this skill to analyze whether a game rewards skillful play and to propose structural improvements.

Engine-neutral contract:

Produce comparable runs for monotonous policies and exploratory policies.
Define the public input schema and visible-state features available to policies.
Keep seeds, tick rate, max duration, policy definitions, search budget, and aggregation logic comparable across runs.
Record score, elapsed time, end state, and telemetry for death, spawn, scoring, input, and usage behavior. Usage is what play actually consists of: how much of the action and score comes from the core mechanic, which parts of the play space are occupied, and how often each threat fires and connects.
When the game has a goal beyond staying alive, add objective-ignoring policies to the comparison: one that stalls to keep scoring, and one that survives without pursuing the goal. A stall that scores more is a signal to examine its cap, its cost, and its whole-run effect, not a defect by itself.
Compute exploratory_ratio = exploratory.best.score / monotonous.max_score.
Treat the ratio as a quality detector, not an optimization target.
Declare an execution profile for every non-baseline policy as well as its visible-state features: oracle (hidden information allowed; upper bound), precise (visible state, near-perfect timing and attention), or human-limited (visible state plus the human limits in references/simulation-harness.md). Compute the ratio from precise policies (search-based runners included, unless labeled oracle); it detects exploits, not difficulty.
Set difficulty, timers, pacing, and progression targets only from human-limited runs, and label every conclusion with the profile it rests on. Without a human-limited run, do not state a difficulty or pacing verdict — report it as not yet measured.
A claim that a strategy dominates, or that a trade-off is balanced, names the profiles it was tested on. If the ranking flips between profiles, that alone is not a balance defect — report it as skill-dependent, but still apply the experience guardrails to each profile's best strategy (a human-limited optimum of idling or waiting is a defect).

Non-deterministic harnesses:

The contract above assumes a seeded forward model. Some rigs cannot provide one — a real browser driven over a wall-clock window, an engine whose RNG you do not control, a policy comparison run against live rendering. Seeding is still the first choice; when it is genuinely unavailable, the following replaces it, and skipping it produces confident conclusions from noise:

evaluating-gameplay-balance