Domains

A domain is a plugin: exactly {oracle, grid, field, loader, learn} on an existing engine, zero core changes. The ConjugateFieldSpec — what observable payoff perturbation h is in this domain — is mandatory and load-bearing: a domain without one (sports) can host λ estimation but not the response instruments, and the library refuses accordingly.

Domain	Engine	Conjugate field	α a priori	Role
congestion	population	link tolls (exactly linear)	0 (exact potential)	calibration standard
blotto	finite	battlefield budgets (experimenter-set)	high	non-potential anchor
pricing	finite	wholesale cost shocks	unknown	flagship application
electricity	finite	fuel cost shocks	unknown	best real-world field
security	finite	synthetic	varies	Tier 2
sports	finite	none	~0 (zero-sum)	Learn-mode only

One page per plugin lands as it ships, including its field spec and data sources.