Architecture

A swap cannot be bounded "per period" on-chain: the period enforcers only accept a literal transfer, and revert on a swap (see Strategies). The way around it is two safes and two delegations: the treasury enforces the per-period budget with a transfer delegation to a dedicated DCA safe, and the agent swaps out of that DCA safe under a balance-change delegation. The DCA safe's balance becomes the real, on-chain per-period cap.

The two-safe model

┌──────────────────┐
│   Treasury safe   │   the real funds
└──────────────────┘
      │
      │  Delegation 1 — periodic transfer (erc20PeriodTransfer)
      │  "at most 50 USDC per week → the DCA safe"
      │  Enforced on-chain: it's a transfer, so the period cap holds.
      ▼
┌──────────────────┐
│    DCA safe       │   the strategy envelope — holds only the released budget
└──────────────────┘
      │
      │  Delegation 2 — the strategy mandate (erc20BalanceChange)
      │  "swap the DCA safe's balance, ≤ cap and ≤ max price per swap"
      │  Enforced on-chain: the balance-change bounds hold on a swap.
      ▼
┌──────────────────┐
│     Uniswap       │
└──────────────────┘

Why this unlocks the per-period cap

• Delegation 1 is a transfer, so erc20PeriodTransfer accepts it and enforces "≤ 50 USDC per week" on-chain. This is exactly what could not be done directly on a swap.
• The DCA safe can only ever hold what the treasury released this period. Even if the agent swaps the entire DCA safe balance, it cannot exceed the weekly budget — because the treasury only lets that much through. The temporal cap becomes real.
• Delegation 2 bounds each swap (max spend + max price) via erc20BalanceChange, as before. The agent still holds nothing; it only redeems.

So the temporal budget (Delegation 1) and the per-swap safety (Delegation 2) are both enforced on-chain, split across the two safes.

Who owns what

• The DCA safe is created by the DAO itself (via the standard Safe interface), with the same owners as the treasury. It is an envelope of the same entity — one per strategy — not a third party. Hourglass does not create it.
• Each safe enables the DeleGator module (the app does this on the safe it runs in), then signs its delegation from there.

What it unlocks

This composes into a real system, not a single feature:

• Multiple strategies — one DCA safe per strategy, each with its own periodic budget and its own bounds. A DAO runs several in parallel without them touching each other.
• Per-strategy agents — a distinct agent assigned to each DCA safe, each with its own enforcers. Compromising one agent bounds the loss to that one DCA safe's budget, never the treasury.
• A clear separation — the treasury is the single source; the DCA safes are bounded envelopes; the agents are replaceable executors.

Critical: sign delegations under the FINAL owner set

A Safe delegation is an EIP-1271 signature that the DelegationManager re-checks at every redeem against the Safe's current owners and threshold (verified in Safe.checkNSignatures, which reads threshold from storage and requires each signer to be a current owner). So changing a Safe's owners or threshold after signing invalidates every delegation it signed — a delegation signed while 1-of-1 reverts (GS020 / GS026 → InvalidERC1271Signature) once the threshold is raised.

What is and isn't sensitive to an owner change:

Rule: put each safe in its final multisig configuration before signing any delegation from it. Installing the module first as 1-of-1 (simple, zero-fund, zero risk) is fine — just reach the final owner set before the delegation signatures.

The operator flow

1. Set up the agent — install the Hourglass agent skill; it creates the agent wallet and returns its address.
2. Create the DCA safe — the DAO creates a new Safe (same owners as the treasury) for this strategy's budget. Enable the DeleGator module (a 1-of-1 setup is fine here — it survives later owner changes), then bring the DCA safe to its final multisig owner set before signing anything.
3. Sign Delegation 2 (from the DCA safe, now at its final owners) — the strategy mandate to the agent (the per-swap bounds).
4. Sign Delegation 1 (from the treasury) — the periodic-transfer delegation to the DCA safe (the per-period budget, enforced on-chain).
5. Fund the treasury path last — with both delegations signed under their final owner sets, let the periodic budget flow. Test the whole wiring at zero funds first if you like; the budget only moves once Delegation 1 is live.
6. Hand the recap to the agent — the strategy context (target, amount, cadence) the agent pairs with the mandates it discovers.

Honest limits

• The DCA safe transiently holds the released budget. This is not fully non-custodial like a single-swap mandate — but the custody sits in a DAO-owned Safe (same owners), bounded per period, never in the agent.
• Per-swap spacing ("once per day") is still off-chain. The period cap bounds the amount released per period, not the number of swaps or their spacing. The cadence remains the agent's responsibility.