78-84: ⚠️ Potential issue

Add validation for transfer_fee in _get_errors method

The docstring for transfer_fee states that this field must not be present if the tfMPTCanTransfer flag is not set, but there is no validation to enforce this rule in the _get_errors method.

Apply this diff to add the validation:

 def _get_errors(self: Self) -> Dict[str, str]:
     errors = super()._get_errors()

+    if self.transfer_fee is not None and not self.flags.get("TF_MPT_CAN_TRANSFER", False):
+        errors["transfer_fee"] = "Field must not be present if tfMPTCanTransfer flag is not set."

     if self.mptoken_metadata is not None:
         if len(self.mptoken_metadata) == 0:
             errors["mptoken_metadata"] = "Field must not be empty string."
         elif bool(HEX_REGEX.fullmatch(self.mptoken_metadata)) is False:
             errors["mptoken_metadata"] = "Field must be in hex format."

197-197: Improved error handling is a good addition

The enhanced error context by including field names in exceptions will help with debugging MPT-related issues.

23-23: Verify SPECIAL_FIELDS constant definition

Let's ensure the SPECIAL_FIELDS constant is properly defined and contains the expected MPT-related fields.

#!/bin/bash
# Description: Check the definition of SPECIAL_FIELDS in uint64.py
# Expected: Should find MPT-related field definitions

rg -A 5 "SPECIAL_FIELDS.*=" xrpl/core/binarycodec/types/uint64.py

192-197: Review special field handling implementation

The changes introduce conditional argument unpacking for fields in SPECIAL_FIELDS. While this supports MPT functionality, we should ensure:

1. The modification maintains backward compatibility with existing field serialization
2. The special field handling aligns with the XLS-33 specification for MPT

#!/bin/bash
# Description: Verify the impact on existing field serialization
# Expected: Should find test cases covering both special and regular field serialization

# Check for existing serialization tests
rg -l "test.*serialization" tests/unit/core/binarycodec/

# Look for MPT-related test cases
rg -l "test.*mpt" tests/unit/core/binarycodec/

#!/bin/bash
# Check the test file content for STObject serialization tests
rg -A 10 "class.*Test.*Object" tests/unit/core/binarycodec/types/

# Look for SPECIAL_FIELDS definition and usage
rg "SPECIAL_FIELDS" xrpl/core/binarycodec/

# Check test cases specifically for field handling in STObject
rg -A 5 "test.*field" tests/unit/core/binarycodec/types/

#!/bin/bash
# Check the SPECIAL_FIELDS definition and related code in uint64
cat xrpl/core/binarycodec/types/uint64.py

# Check the complete STObject implementation to understand the context
cat xrpl/core/binarycodec/types/st_object.py

# Look for test cases that might cover uint64 special fields
rg -l "test.*uint64" tests/unit/core/binarycodec/types/

4-4: LGTM! Import statements are well-organized.

The new imports are properly organized and necessary for implementing the MPT functionality.

Also applies to: 14-14, 19-25

159-159: ⚠️ Potential issue

Fix assertion to check clawback transaction result

The assertion is checking auth_res.result["engine_result"] instead of response.result["engine_result"].

-        self.assertEqual(auth_res.result["engine_result"], "tesSUCCESS")
+        self.assertEqual(response.result["engine_result"], "tesSUCCESS")

7-7: LGTM! Import statements are well-organized.

The new imports are properly organized and necessary for implementing the MPT functionality.

Also applies to: 9-9, 11-11

158-169: ⚠️ Potential issue

Retrieve mpt_issuance_id directly from transaction response

The current method of retrieving mpt_issuance_id from account_objects[0] is unreliable if multiple MPTokenIssuance objects exist.

-        # confirm MPTokenIssuance ledger object was created
-        account_objects_response = await client.request(
-            AccountObjects(account=WALLET.address, type=AccountObjectType.MPT_ISSUANCE)
-        )
-
-        # subsequent integration tests (sync/async + json/websocket) add one
-        # MPTokenIssuance object to the account
-        account_objects = account_objects_response.result["account_objects"]
-        self.assertTrue(len(account_objects) > 0)
-
-        mpt_issuance_id = account_objects[0]["mpt_issuance_id"]
+        # Retrieve mpt_issuance_id from transaction response
+        mpt_issuance_id = response.result["meta"]["mpt_issuance_id"]

4-4: LGTM! Import statements are well-organized.

The new imports for MPT-related functionality are properly structured and necessary for the implementation.

Also applies to: 14-14, 19-24

84-170: LGTM! Well-structured test with comprehensive coverage.

The test thoroughly covers the MPT clawback workflow:

1. MPT creation with clawback flag
2. Authorization
3. Payment
4. Clawback execution
5. Balance verification

After fixing the identified issues, this will provide good test coverage for the MPT clawback feature.

158-159: ⚠️ Potential issue

Fix assertion to check the correct response

The test is asserting the result of the authorization response instead of the clawback response.

         self.assertTrue(response.is_successful())
-        self.assertEqual(auth_res.result["engine_result"], "tesSUCCESS")
+        self.assertEqual(response.result["engine_result"], "tesSUCCESS")

168-170: ⚠️ Potential issue

Update balance assertion after clawback

The assertion checks for the same balance ("9223372036854775807") after clawback of 500 tokens. The balance should be reduced.

         self.assertEqual(
-            ledger_entry_res.result["node"]["MPTAmount"], "9223372036854775807"
+            ledger_entry_res.result["node"]["MPTAmount"], "9223372036854775307"  # Original value - 500
         )

4-4: LGTM! Import statements are properly organized.

The new imports for MPT-related functionality are correctly added and well-organized.

Also applies to: 14-14, 19-24

Line range hint 33-82: Skipping review of unchanged test method.

158-159: ⚠️ Potential issue

Correct the assertion to check the clawback transaction result

The test is asserting the engine_result of auth_res (authorization response) instead of response (clawback response).

self.assertTrue(response.is_successful())
-self.assertEqual(auth_res.result["engine_result"], "tesSUCCESS")
+self.assertEqual(response.result["engine_result"], "tesSUCCESS")

168-170: ⚠️ Potential issue

Update balance assertion after clawback

The test asserts an incorrect balance after clawback. The final balance should be reduced by 500 tokens.

self.assertEqual(
-    ledger_entry_res.result["node"]["MPTAmount"], "9223372036854775307"
+    ledger_entry_res.result["node"]["MPTAmount"], "9223372036854774807"  # Initial amount (9223372036854775807) - clawback amount (500)
)

144-156: Verify holder's address in clawback response

Consider adding validation to ensure the holder's address is correctly reflected in the clawback transaction response.