diff --git a/src/ipc/capnp/mining.capnp b/src/ipc/capnp/mining.capnp
index 7e5cced6f31..1811716ff54 100644
--- a/src/ipc/capnp/mining.capnp
+++ b/src/ipc/capnp/mining.capnp
@@ -21,7 +21,7 @@ interface Mining $Proxy.wrap("interfaces::Mining") {
     isTestChain @0 (context :Proxy.Context) -> (result: Bool);
     isInitialBlockDownload @1 (context :Proxy.Context) -> (result: Bool);
     getTip @2 (context :Proxy.Context) -> (result: Common.BlockRef, hasResult: Bool);
-    waitTipChanged @3 (context :Proxy.Context, currentTip: Data, timeout: Float64) -> (result: Common.BlockRef);
+    waitTipChanged @3 (context :Proxy.Context, currentTip: Data, timeout: Float64 = .maxDouble) -> (result: Common.BlockRef);
     createNewBlock @4 (options: BlockCreateOptions) -> (result: BlockTemplate);
     checkBlock @5 (block: Data, options: BlockCheckOptions) -> (reason: Text, debug: Text, result: Bool);
 }
@@ -43,19 +43,19 @@ interface BlockTemplate $Proxy.wrap("interfaces::BlockTemplate") {
 }
 
 struct BlockCreateOptions $Proxy.wrap("node::BlockCreateOptions") {
-    useMempool @0 :Bool $Proxy.name("use_mempool");
-    blockReservedWeight @1 :UInt64 $Proxy.name("block_reserved_weight");
-    coinbaseOutputMaxAdditionalSigops @2 :UInt64 $Proxy.name("coinbase_output_max_additional_sigops");
+    useMempool @0 :Bool = true $Proxy.name("use_mempool");
+    blockReservedWeight @1 :UInt64 = .defaultBlockReservedWeight $Proxy.name("block_reserved_weight");
+    coinbaseOutputMaxAdditionalSigops @2 :UInt64 = .defaultCoinbaseOutputMaxAdditionalSigops $Proxy.name("coinbase_output_max_additional_sigops");
 }
 
 struct BlockWaitOptions $Proxy.wrap("node::BlockWaitOptions") {
-    timeout @0 : Float64 $Proxy.name("timeout");
-    feeThreshold @1 : Int64 $Proxy.name("fee_threshold");
+    timeout @0 : Float64 = .maxDouble $Proxy.name("timeout");
+    feeThreshold @1 : Int64 = .maxMoney $Proxy.name("fee_threshold");
 }
 
 struct BlockCheckOptions $Proxy.wrap("node::BlockCheckOptions") {
-    checkMerkleRoot @0 :Bool $Proxy.name("check_merkle_root");
-    checkPow @1 :Bool $Proxy.name("check_pow");
+    checkMerkleRoot @0 :Bool = true $Proxy.name("check_merkle_root");
+    checkPow @1 :Bool = true $Proxy.name("check_pow");
 }
 
 struct CoinbaseTx $Proxy.wrap("node::CoinbaseTx") {
diff --git a/test/functional/interface_ipc_mining.py b/test/functional/interface_ipc_mining.py
index d4a0d87e767..a02727bb4c9 100755
--- a/test/functional/interface_ipc_mining.py
+++ b/test/functional/interface_ipc_mining.py
@@ -243,9 +243,6 @@ class IPCMiningTest(BitcoinTestFramework):
 
             async with AsyncExitStack() as stack:
                 opts = self.capnp_modules['mining'].BlockCreateOptions()
-                opts.useMempool = True
-                opts.blockReservedWeight = 4000
-                opts.coinbaseOutputMaxAdditionalSigops = 0
                 template = await mining_create_block_template(mining, stack, ctx, opts)
                 assert template is not None
                 block = await mining_get_block(template, ctx)
@@ -351,12 +348,7 @@ class IPCMiningTest(BitcoinTestFramework):
 
     def run_test(self):
         self.miniwallet = MiniWallet(self.nodes[0])
-        self.default_block_create_options = self.capnp_modules['mining'].BlockCreateOptions(
-            useMempool=True,
-            blockReservedWeight=4000,
-            coinbaseOutputMaxAdditionalSigops=0
-        )
-
+        self.default_block_create_options = self.capnp_modules['mining'].BlockCreateOptions()
         self.run_mining_interface_test()
         self.run_block_template_test()
         self.run_coinbase_and_submission_test()