Compound V3

One immutable meta-adapter that reports an account's position in any Compound V3 (Comet) market — base-token supply or borrow, every collateral leg, and unclaimed COMP rewards.

One immutable meta-adapter that reports an account's position in any Compound V3 (Comet) market — base-token supply or borrow, every collateral leg, and unclaimed COMP rewards. Which comets it queries is a governed instance set on the NAV Calculator; the adapter holds no per-comet state. Read math is delegated to CompoundV3CometLib.

• Type: Meta-adapter
• protocolSubId: keccak256("compound-v3-comets")
• Instance key: the comet (market) address, widened to bytes32
• Source: CompoundV3CometsMetaBalanceAdapter.sol

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Positions returned

Leg	PositionKind	isDebt	Description
Base supply	Supplied	false	Positive base position, present value
Base borrow	Borrowed	true	Negative base position, present value
Collateral	Collateral	false	One leg per collateral asset with a non-zero balance
Rewards	Rewards	false	Unclaimed reward token (COMP)

The base leg is supply or borrow depending on the sign of the net base position (never both). Each leg is dropped if its amount is zero, its asset is unregistered, or it is excluded by assetFilter. A multi-role asset (e.g. COMP as both collateral and reward) emits one leg per role.

Where the net base position is a borrow and the base asset is unregistered, the comet reports nothing — collateral and rewards included — rather than emitting credit legs with no offsetting debt. See Never report collateral without its debt.

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Balance calculation

Compound V3 adapter — how the underlying balances reported to the NAV Calculator are derived.

CompoundV3CometLib.accountData(comet, rewards, rewardToken, account) returns the net base, collateral balances, and unclaimed reward, accruing interest and reward indices to block.timestamp (it re-derives Comet's accrual rather than mutating state).

baseNet = userBasic(account).principal * (principal >= 0 ? baseSupplyIndex : baseBorrowIndex) / BASE_INDEX_SCALE
          (indices first advanced by the elapsed-time accrual)
  baseNet > 0 → Supplied, amount =  baseNet
  baseNet < 0 → Borrowed, amount = -baseNet

collateralBalances[i] = comet.collateralBalanceOf(account, asset[i])   // per collateral asset

rewardOwed = accrued − rewardsClaimed(comet, account), floored at 0

Reward accrual mirrors Comet's tracking-index math, handling the optional 4th multiplier/rescaleFactor field returned by some chains' rewardConfig (detected via returndata length). The library is a leg-for-leg, fork-tested port of the per-comet adapter.

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Identity

• positionId: abi.encode(address comet) — the comet address (all legs of a comet share it)
• positionKind: Supplied · Borrowed · Collateral · Rewards

There is no labels field on the position. The adapter implements positionLabels(positionId), which returns ["Market", "<comet symbol()>"] (e.g. "cUSDCv3") from the comet's on-chain symbol — surfaced only by the verbose reads (getAccountPositionsVerbose / getAccountNavVerbose); the full breadcrumb is [protocolName, ...labels].

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Constructor

constructor(address compoundRewards_, address rewardToken_, address navCalculator_)

Parameter	Description
compoundRewards_	The chain's CometRewards contract (shared by every comet on the chain; must be a contract)
rewardToken_	The reward token, COMP or its bridged form (must be non-zero)
navCalculator_	NAV Calculator contract (asset registry + instance set)

compoundRewards_ and rewardToken_ are chain-level constants pinned once here, so they apply across every comet in the instance set.

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Registration

Meta-adapter. Register once and seed its comets with addMetaBalanceAdapter(adapter, instances), then adjust with addMetaInstances(adapter, instances) / removeMetaInstances(adapter, instances) (MANAGER-gated). Each instance coordinate is a comet address widened to bytes32 (decoded via _toAddress). Adding a new comet is a config call — no new deploy.