refine blockchain integration and protocols

CONTEXT.md

@@ -51,9 +51,37 @@ _Avoid_: reputation, rating, rank
 ### Payments & fraud
 
 **Stake**:
-Tokens a node locks as collateral that can be slashed for fraud. Stake protects the network economically, but route selection is not based on a node's token balance.
+Collateral a node stands to lose for fraud. In the current design the node's Pending Balance serves as stake — no upfront deposit is required. An optional USDT/TAI deposit may return later for routing priority.
 _Avoid_: deposit, bond, escrow
 
+**Treasury**:
+The single project-owned Solana wallet that custodially holds client deposits, pays node payouts, and accumulates the Protocol Cut. Its keypair is loaded only on settlement-capable trackers.
+_Avoid_: escrow, vault, hot wallet
+
+**Pending Balance**:
+A node's accrued, not-yet-paid USDT earnings on the tracker ledger. Doubles as the node's fraud collateral: it is forfeited in full when a validator catches a divergent output.
+_Avoid_: unpaid rewards, accrual, balance due
+
+**Settlement Period**:
+The dynamic interval driving on-chain payouts: a node is paid when its Pending Balance exceeds the Payout Threshold or the period elapses, whichever comes first. Short in development (seconds), long in production (daily), configurable to grow with volume.
+_Avoid_: epoch, payout cycle, billing cycle
+
+**Payout Threshold**:
+The minimum Pending Balance that triggers an immediate payout before the Settlement Period elapses. Includes a dust floor so payouts are never smaller than they are worth.
+_Avoid_: minimum payout, dust limit
+
+**Protocol Cut**:
+The 10% of inference fees retained by the project for infrastructure; the remaining 90% goes to the nodes that served the request. Accumulates in the Treasury as the future TAI liquidity reserve.
+_Avoid_: spread, commission, house fee
+
+**Deposit Watcher**:
+The tracker component that observes the Treasury's on-chain USDT deposits and credits the sending client's API-key ledger balance.
+_Avoid_: payment listener, chain scanner
+
+**Mock USDT**:
+The self-created 6-decimal SPL mint that stands in for USDT on devnet, where real USDT does not exist. The mint address is configuration, so mainnet cutover is a config change.
+_Avoid_: test token, fake USDT, devnet dollar
+
 **Tax**:
 The share of caller payments distributed to compute nodes as rewards. Taxes are weighted by completed work and historical node speed so faster, larger nodes earn proportionally more.
 _Avoid_: fee, toll, commission
@@ -67,8 +95,8 @@ Work a compute node performs without earning immediate rewards, usually during p
 _Avoid_: unpaid labor, warmup request
 
 **Slash**:
-The act of reducing a node's stake as a penalty for a proven fraud incident.
-_Avoid_: penalize, burn, fine
+The penalty for a proven fraud incident: the node's entire Pending Balance is forfeited to the Treasury and a Strike is recorded.
+_Avoid_: penalize, burn, fine, forfeit
 
 **Strike**:
 A fraud incident recorded on-chain against a node. Enough strikes result in a ban.
@@ -83,7 +111,7 @@ The first N jobs a new wallet must complete without earning, to raise the cost o
 _Avoid_: trial period, warmup, grace period
 
 **Token**:
-Our native Solana L2 token. Used by nodes for staking and received as inference rewards. Clients never need to hold it.
+TAI, our native Solana SPL token. Deferred (ADR-0015): nodes are currently paid directly in USDT; TAI returns as the reward/upside layer once volume exists, funded by the accumulated Protocol Cut. Clients never need to hold it.
 _Avoid_: coin, reward token, native token
 
 **Contract Boundary**:
@@ -105,7 +133,7 @@ _Avoid_: accusation, report, claim
 ### Client-facing
 
 **Client**:
-Any application or user that sends inference requests to the gateway. Pays in SOL or USDC.
+Any application or user that sends inference requests to the gateway. Prepays USDT into the Treasury; each request is metered against the resulting ledger balance at a per-1K-tokens price set per model.
 _Avoid_: user, caller, consumer
 
 **Model Preset**: