# Coverage Key — L5 Invisible Commons

## Problem in brief
Independent, competing farms pump from a shared underground aquifer. The stock is invisible and expensive/slow to measure; it refills extremely slowly; and crossing a hidden drawdown threshold causes *permanent, irreversible* capacity loss (ground compaction). No central owner; each farm has strong near-term reasons to keep pumping. A regional body can set rules, fund measurement, and change information/accountability — but cannot cheaply meter every well or alter the reserve's physics. Success = stay above the point of no return AND keep farms viable.

## Chosen archetypes
1. **Commons Governance** (primary) — many actors drawing on a shared, depletable resource where private gain diverges from collective viability; the core structure. Supplies the governance scaffold: boundary, access/use rules, monitoring, sanctions, replenishment, legitimacy, dispute handling, adaptation.
2. **State Estimation** (secondary — the "invisible" facet) — the resource state that all decisions hinge on is hidden, noisy, and costly to observe directly; must be inferred from sparse/indirect evidence with uncertainty carried explicitly. This is what makes L5 distinct from an ordinary commons.
3. **Option Preservation** (secondary — the "irreversible threshold" facet) — past a point the loss is permanent and uncreatable; the design must keep a safety margin and avoid betting the reserve on uncertain estimates.

## Coverage Key — load-bearing components a complete design MUST address

1. **Resource boundary & shared-stock definition** — Name what is being protected (the aquifer reserve, its slow recharge, the compaction damage pathway), who the users are, and the system's edges (e.g. recharge zones, neighboring basins). Without this you cannot tell success from failure.

2. **Access & use limits tied to capacity** — Per-farm pumping caps/quotas (or tradable rights) that connect allowable extraction to the reserve's actual condition and recharge rate, not to arbitrary numbers.

3. **Hidden-state estimation of the reserve** — Infer the true reserve level and trajectory from sparse, expensive, indirect signals (sample wells, proxies, models), since direct full metering is infeasible. The estimate, not a raw reading, drives decisions. **[HARD]** — A quick designer treats "fund measurement" as solved once a few gauges exist; but the problem states measurement is expensive/slow, so the real work is *inferring* state from partial data, not reading it.

4. **Uncertainty carried with the estimate** — Represent confidence/error bands on the reserve estimate and let action thresholds reflect the cost of being wrong. **[HARD]** — Easy to model the aquifer as a single confident number; given irreversibility, acting on a point estimate that is optimistically biased can silently blow past the threshold before anyone is sure.

5. **Irreversibility margin / option preservation (safety buffer above the threshold)** — Set the operating limit well *above* the permanent-loss point, sized to estimation uncertainty and recharge lag, so the reserve is never bet on a hopeful guess. Once crossed, no recovery is possible. **[HARD]** — Under near-term pumping pressure the natural design hugs the threshold to maximize current use; but the asymmetry (permanent, uncreatable loss vs. recoverable shortfall) demands a deliberate, conservative buffer that a speed-oriented designer under-builds.

6. **Monitoring of behavior (not just resource)** — Observe/verify each farm's actual extraction, given that wells cannot all be cheaply metered. Needs proxy/audit/self-report-plus-verification design so cheating is detectable. **[HARD]** — "Can't cheaply meter every well" is stated as a hard constraint; without a credible behavior-monitoring scheme (e.g. statistical audits, energy-use proxies, satellite/remote sensing, peer reporting) quotas are unenforceable and collapse into the original race.

7. **Sanctions / consequences for over-extraction** — Graduated, proportional penalties that make overuse and evasion costlier than compliance, so quotas bite.

8. **Incentive alignment for competing actors** — Restructure payoffs so each independent farm's rational self-interest favors restraint (e.g. tradable rights, shared stake in reserve health, reciprocity/repeated-game framing), not just rules imposed top-down. Farms compete and have strong near-term reasons to pump.

9. **Legitimacy basis for the regional body's rules** — Why farms accept the rules and enforcement: participation, transparent evidence, fairness — otherwise rules are evaded or politically captured. The regional body sets rules but relies on compliance, not omniscient force.

10. **Replenishment / demand-management duties** — Active measures that ease drawdown toward the recharge rate (efficiency requirements, recharge support, demand reduction), since the reserve refills extremely slowly and cannot be "topped up" on demand.

11. **Adaptation cadence with condition triggers** — Periodic rule revision keyed to updated reserve estimates and to recalibration of the estimation model, since both demand and knowledge of the reserve change over time. Static quotas become wrong as conditions shift.

12. **Farm-viability constraint** — Limits must be calibrated so they do not destroy the farms' operating viability; the success criterion explicitly fails if rules are so harsh the farms die. Forces a least-coercive, viability-preserving rule set rather than a blunt shutdown.

13. **Dispute resolution & exception path** — A trusted process for contesting quotas, audit findings, and edge cases, so enforcement stays fair and conflicts don't degrade cooperation.

## [HARD] flags — summary
- **#3 Hidden-state estimation** — measurement is expensive/slow; the task is inference from partial data, not just installing gauges.
- **#4 Uncertainty on the estimate** — a confident single number plus irreversibility invites silently overshooting the threshold.
- **#5 Irreversibility safety buffer** — near-term pumping pressure pushes designs to hug the threshold; the permanent-loss asymmetry demands a conservative margin.
- **#6 Behavior monitoring under un-meterable wells** — the explicit "can't cheaply meter every well" constraint makes enforcement, not rule-writing, the bottleneck.
