Update control tool and create Hydration failure refund command

control/.claude/skills/snowbridge-referendum/SKILL.md

@@ -0,0 +1,145 @@
+---
+name: snowbridge-referendum
+description: Generate a Snowbridge preimage, create opengov referendum calls, test with referenda-tester (including XCM verification on BridgeHub), and report results
+disable-model-invocation: true
+allowed-tools: Bash, Read, Write, Grep, Glob
+argument-hint: <snowbridge-subcommand> [--track <track>] [--network <network>]
+---
+
+# Snowbridge Referendum Workflow
+
+End-to-end workflow: generate a Snowbridge governance preimage, create opengov referendum calls with opengov-cli, test them with the referenda-tester (including XCM relay verification on BridgeHub), and report results ready for on-chain submission.
+
+## Arguments
+
+- `$0`: The snowbridge-preimage subcommand (e.g. `mint-feb2026`, `upgrade-v2`, `pricing-parameters`, etc.)
+- Remaining args (`$ARGUMENTS`): May include `--track` and `--network` overrides.
+  - `--track`: `whitelisted-caller` (default) or `root`
+  - `--network`: `polkadot` (default), `kusama`, `westend`, `paseo`
+
+## Project Locations
+
+- Snowbridge preimage tool: `./preimage/` (relative to this control directory)
+- opengov-cli: `../../opengov-cli/` (relative to this control directory)
+
+## Steps
+
+### 1. Generate the preimage
+
+Run the snowbridge preimage tool:
+
+```bash
+cd <snowbridge-control-dir>/preimage && cargo run --features <network> -- <subcommand> [extra-flags]
+```
+
+- The `--features` flag must match the network: `polkadot`, `kusama`, `westend`, or `paseo`.
+- Capture the hex output (the line starting with `0x`) from stdout.
+- Capture the preimage hash and size from stderr (lines like `Preimage hash: 0x...` and `Preimage size: N`).
+- Save the hex to `preimage.txt` in the opengov-cli project root.
+
+### 2. Run opengov-cli
+
+From the opengov-cli directory:
+
+```bash
+cargo run -- submit-referendum --proposal preimage.txt --network <network> --track <track> --output calldata
+```
+
+Parse the output to extract these hex values:
+- **Fellowship referendum call**: line after "Open a Fellowship referendum to whitelist the call:" (only for whitelisted-caller track)
+- **Governance batch call**: line after "Batch to submit on Polkadot Asset Hub:" (or the relevant chain)
+- **Collectives batch call**: line after "Batch to submit on Polkadot Collectives Chain:" (only for whitelisted-caller track)
+
+For `--track root`, there is no fellowship call or collectives batch.
+
+### 3. Test with referenda-tester
+
+This is the critical verification step. The referenda-tester simulates the full governance flow using Chopsticks.
+
+#### Determine additional chains
+
+If the preimage sends XCM to other chains (e.g. BridgeHub), add them via `--additional-chains`. This is essential for verifying the XCM roundtrip completes successfully.
+
+Common patterns:
+- **Preimage contains `PolkadotXcm::send` to BridgeHub** (e.g. mint, replay, upgrade commands): add BridgeHub
+- **Preimage is AH-local only** (e.g. treasury spend, register asset): no additional chains needed
+
+To determine this: check if the preimage tool's subcommand uses `send_xcm_bridge_hub()` in `commands.rs`. If so, BridgeHub is needed.
+
+#### Whitelisted-caller track (default)
+
+```bash
+npx github:karolk91/polkadot-referenda-tester test \
+  --governance-chain-url wss://asset-hub-polkadot-rpc.n.dwellir.com \
+  --fellowship-chain-url wss://polkadot-collectives-rpc.polkadot.io \
+  --call-to-create-governance-referendum '<governance-batch-hex>' \
+  --call-to-create-fellowship-referendum '<collectives-batch-hex>' \
+  --additional-chains wss://bridge-hub-polkadot-rpc.n.dwellir.com \
+  --verbose
+```
+
+#### Root track
+
+```bash
+npx github:karolk91/polkadot-referenda-tester test \
+  --governance-chain-url wss://asset-hub-polkadot-rpc.n.dwellir.com \
+  --call-to-create-governance-referendum '<governance-batch-hex>' \
+  --additional-chains wss://bridge-hub-polkadot-rpc.n.dwellir.com \
+  --verbose
+```
+
+Omit `--fellowship-chain-url` and `--call-to-create-fellowship-referendum` for root track.
+Omit `--additional-chains` if the preimage doesn't send XCM to other chains.
+
+#### Testnet URLs
+
+| Network | Asset Hub | Collectives | BridgeHub |
+|---------|-----------|-------------|-----------|
+| Polkadot | `wss://asset-hub-polkadot-rpc.n.dwellir.com` | `wss://polkadot-collectives-rpc.polkadot.io` | `wss://bridge-hub-polkadot-rpc.n.dwellir.com` |
+| Kusama | `wss://asset-hub-kusama-rpc.n.dwellir.com` | `wss://kusama-collectives-rpc.n.dwellir.com` | `wss://bridge-hub-kusama-rpc.n.dwellir.com` |
+| Westend | `wss://asset-hub-westend-rpc.n.dwellir.com` | `wss://westend-collectives-rpc.n.dwellir.com` | `wss://bridge-hub-westend-rpc.n.dwellir.com` |
+
+### 4. Verify the referenda-tester output
+
+Check the output for these success indicators:
+
+#### Governance dispatch
+- `Both referenda executed successfully!` (or single referendum for root track)
+- `Scheduler.Dispatched` with `result: success`
+- `Whitelist.WhitelistedCallDispatched` with `result: success` (whitelisted-caller track)
+
+#### XCM to BridgeHub (if applicable)
+- `PolkadotXcm.Sent` with destination `Parachain: 1002` (BridgeHub)
+- `XcmpQueue.XcmpMessageSent` on Asset Hub
+- Outbound HRMP message to recipient `1002` in the Chopsticks logs
+
+#### BridgeHub processing (if additional chain added)
+- `MessageQueue.Processed` with `origin: Sibling(1000)` and `success: true`
+- `PolkadotXcm.Sent` from BridgeHub back to AH (destination `Parachain: 1000`)
+- `XcmpQueue.XcmpMessageSent` on BridgeHub
+- Outbound HRMP message to recipient `1000` in the Chopsticks logs
+
+For commands that mint/deposit assets (e.g. `mint-feb2026`, `replay-sep2025`), verify the return XCM contains:
+- `ReserveAssetDeposited` with the correct asset and amount
+- `DepositAsset` with the correct beneficiary
+- The asset location should be the expected foreign asset (e.g. Ethereum ERC20)
+
+#### Failure investigation
+If the test fails:
+- Check `Scheduler.Dispatched` result for errors
+- Look for `XcmpQueue.Fail` or `MessageQueue.ProcessingFailed` events
+- Check BridgeHub events for `Transact` failures
+- Inspect the Chopsticks `outboundHrmpMessage` logs to see if XCM was sent
+
+### 5. Report results
+
+Print a summary including:
+- Preimage hash and size
+- Whether all referenda passed
+- Whether XCM roundtrip completed (if applicable)
+- The final call data for posting:
+  - Governance batch (submit on Asset Hub)
+  - Collectives batch (submit on Collectives, whitelisted-caller only)
+- Any issues found during testing
+
+If everything passes, the calls are ready for on-chain submission.

control/preimage/src/commands.rs

@@ -861,7 +861,7 @@ pub fn replay_sep_2025_xcm() -> crate::asset_hub_runtime::RuntimeCall {
             Instruction::*,
             Xcm,
         },
-        xcm::{VersionedLocation, VersionedXcm, v3::WeightLimit},
+        xcm::{v3::WeightLimit, VersionedLocation, VersionedXcm},
     };
     use hex_literal::hex;
 
@@ -916,12 +916,10 @@ pub fn replay_sep_2025_xcm() -> crate::asset_hub_runtime::RuntimeCall {
         ),
     ];
 
-    let mut all_instructions = vec![
-        UnpaidExecution {
-            weight_limit: WeightLimit::Unlimited,
-            check_origin: None,
-        },
-    ];
+    let mut all_instructions = vec![UnpaidExecution {
+        weight_limit: WeightLimit::Unlimited,
+        check_origin: None,
+    }];
 
     // Add all failed messages as separate ExportMessage instructions
     for (asset_type, amount, beneficiary_address, topic) in failed_messages.iter() {
@@ -973,14 +971,102 @@ pub fn replay_sep_2025_xcm() -> crate::asset_hub_runtime::RuntimeCall {
         all_instructions.push(SetTopic(*topic));
     }
 
-    let asset_hub_xcm = crate::asset_hub_runtime::RuntimeCall::PolkadotXcm(pallet_xcm::pallet::Call::send {
+    let asset_hub_xcm =
+        crate::asset_hub_runtime::RuntimeCall::PolkadotXcm(pallet_xcm::pallet::Call::send {
+            dest: Box::new(VersionedLocation::V5(Location {
+                parents: 1,
+                interior: Junctions::X1([Junction::Parachain(crate::constants::BRIDGE_HUB_ID)]),
+            })),
+            message: Box::new(VersionedXcm::V5(Xcm(all_instructions))),
+        });
+    asset_hub_xcm
+}
+
+/// Mint refund for a failed Hydration→Ethereum USDT transfer (Feb 2026).
+///
+/// Transaction: 0xcce3ccdd216ad59c2c602987fe7e8e77ab68dbe83a4555dff630ea346a512c2a
+/// The transfer failed on BridgeHub and the user's USDT was burnt on AssetHub.
+/// This sends XCM from BridgeHub→AssetHub with ReserveAssetDeposited to mint
+/// the USDT back to the beneficiary.
+pub fn mint_feb_2026_xcm() -> BridgeHubRuntimeCall {
+    use crate::bridge_hub_runtime::runtime_types::{
+        pallet_xcm,
+        staging_xcm::v5::{
+            asset::{Asset, AssetFilter, AssetId, Assets, Fungibility, WildAsset},
+            junction::Junction,
+            junctions::Junctions,
+            location::Location,
+            Instruction::*,
+            Xcm,
+        },
+        xcm::{v3::WeightLimit, VersionedLocation, VersionedXcm},
+    };
+    use hex_literal::hex;
+
+    // USDT (Tether) ERC20 on Ethereum Mainnet
+    let usdt_address: [u8; 20] = hex!("dac17f958d2ee523a2206206994597c13d831ec7");
+    // 499.739459 USDT (6 decimals) - exact on-chain amount from extrinsic 11369277-3
+    let usdt_amount: u128 = 499_739_459;
+
+    // Beneficiary: 16AQJHpSRMh5X1mULm4dCgYxrQLsrnK3uwCQ436iitYk1ru7 (Hydration sender)
+    let beneficiary: [u8; 32] =
+        hex!("e458cde73940bd29d637face28de378dfb933f21734cfb1d24a0edfb4b81f31c");
+
+    // USDT location: Ethereum ERC20 foreign asset
+    let usdt_location = Location {
+        parents: 2,
+        interior: Junctions::X2([
+            Junction::GlobalConsensus(
+                crate::bridge_hub_runtime::runtime_types::staging_xcm::v5::junction::NetworkId::Ethereum {
+                    chain_id: crate::bridge_hub_runtime::CHAIN_ID,
+                },
+            ),
+            Junction::AccountKey20 {
+                network: None,
+                key: usdt_address,
+            },
+        ]),
+    };
+
+    // XCM message from BridgeHub to AssetHub:
+    // BridgeHub is the reserve for Ethereum-bridged assets, so ReserveAssetDeposited
+    // will mint the USDT on AssetHub.
+    let instructions = vec![
+        ReserveAssetDeposited(Assets(vec![Asset {
+            id: AssetId(usdt_location.clone()),
+            fun: Fungibility::Fungible(usdt_amount),
+        }])),
+        ClearOrigin,
+        BuyExecution {
+            fees: Asset {
+                id: AssetId(usdt_location),
+                fun: Fungibility::Fungible(usdt_amount),
+            },
+            weight_limit: WeightLimit::Unlimited,
+        },
+        DepositAsset {
+            assets: AssetFilter::Wild(WildAsset::AllCounted(1)),
+            beneficiary: Location {
+                parents: 0,
+                interior: Junctions::X1([Junction::AccountId32 {
+                    network: None,
+                    id: beneficiary,
+                }]),
+            },
+        },
+        SetTopic(hex!(
+            "cce3ccdd216ad59c2c602987fe7e8e77ab68dbe83a4555dff630ea346a512c2a"
+        )),
+    ];
+
+    // BridgeHub sends XCM to AssetHub via pallet_xcm::send
+    BridgeHubRuntimeCall::PolkadotXcm(pallet_xcm::pallet::Call::send {
         dest: Box::new(VersionedLocation::V5(Location {
             parents: 1,
-            interior: Junctions::X1([Junction::Parachain(crate::constants::BRIDGE_HUB_ID)]),
+            interior: Junctions::X1([Junction::Parachain(crate::constants::ASSET_HUB_ID)]),
         })),
-        message: Box::new(VersionedXcm::V5(Xcm(all_instructions))),
-    });
-    asset_hub_xcm
+        message: Box::new(VersionedXcm::V5(Xcm(instructions))),
+    })
 }
 
 #[cfg(feature = "polkadot")]