add

book/SUMMARY.md

@@ -13,6 +13,7 @@
   - [L2 Node Setup](./advanced/node-setup.md)
   - [Block Data CLI Tool](./advanced/block-data.md)
   - [Proposer](./advanced/proposer.md)
+  - [Toggle Optimistic Mode](./advanced/toggle-optimistic.md)
   - [Kurtosis](./advanced/kurtosis.md)
   - [Upgrade to a new `op-succinct` version](./advanced/upgrade.md)
 - [`OPSuccinctL2OutputOracle`](./contracts/intro.md)

book/advanced/toggle-optimistic.md

@@ -0,0 +1,37 @@
+# Toggle Optimistic Mode
+
+Optimistic mode is a feature that allows the L2OutputOracle to accept outputs without verification (mirroring the original `L2OutputOracle` contract). This is useful for testing and development purposes, and as a fallback for when `OPSuccinctL2OutputOracle` is unable to verify outputs.
+
+When optimistic mode is enabled, the `OPSuccinctL2OutputOracle`'s `proposeL2Output` function will match the interface of the original L2OutputOracle contract, with the modification that the proposer address must be in the `approvedProposers` mapping, or permissionless proposing must be enabled.
+
+## Enable Optimistic Mode
+
+To enable optimistic mode, call the `enableOptimisticMode` function on the `OPSuccinctL2OutputOracle` contract.
+
+```solidity
+function enableOptimisticMode(uint256 _finalizationPeriodSeconds) external onlyOwner whenNotOptimistic {
+    finalizationPeriodSeconds = _finalizationPeriodSeconds;
+    optimisticMode = true;
+    emit OptimisticModeToggled(true, _finalizationPeriodSeconds);
+}
+```
+
+Ensure that the `finalizationPeriodSeconds` is set to a value that is appropriate for your use case. The standard setting is 1 week (604800 seconds).
+
+The `finalizationPeriodSeconds` should never be 0.
+
+## Disable Optimistic Mode
+
+By default, optimistic mode is disabled. To switch back to validity mode, call the `disableOptimisticMode` function on the `OPSuccinctL2OutputOracle` contract.
+
+```solidity
+function disableOptimisticMode(uint256 _finalizationPeriodSeconds) external onlyOwner whenOptimistic {
+    finalizationPeriodSeconds = _finalizationPeriodSeconds;
+    optimisticMode = false;
+    emit OptimisticModeToggled(false, _finalizationPeriodSeconds);
+}
+```
+
+Set the `finalizationPeriodSeconds` to a value that is appropriate for your use case. An example configuration is 1 hour (3600 seconds).
+
+The `finalizationPeriodSeconds` should never be 0.