From ef905c0f7524d76acb31d13ae3101e4e601d218e Mon Sep 17 00:00:00 2001
From: 0xMosas <tosinolosasa@gmail.com>
Date: Thu, 26 Feb 2026 18:09:49 +0100
Subject: [PATCH 1/2] fix(contract): skip fee transfer when fee is zero

Guard the fee stx-transfer? call with a check for fee > 0.
Previously, setting fee-basis-points to 0 would cause tips to
fail because stx-transfer? rejects zero-amount transfers.
---
 contracts/tipstream.clar | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/contracts/tipstream.clar b/contracts/tipstream.clar
index 75e2aa32..c56821a4 100644
--- a/contracts/tipstream.clar
+++ b/contracts/tipstream.clar
@@ -111,7 +111,10 @@
         (asserts! (not (default-to false (map-get? blocked-users { blocker: recipient, blocked: tx-sender }))) err-user-blocked)
         
         (try! (stx-transfer? net-amount tx-sender recipient))
-        (try! (stx-transfer? fee tx-sender (var-get contract-owner)))
+        (if (> fee u0)
+            (try! (stx-transfer? fee tx-sender (var-get contract-owner)))
+            true
+        )
         
         (map-set tips
             { tip-id: tip-id }

From a20f504c8a2cf001d64ed864a2150c384f936d70 Mon Sep 17 00:00:00 2001
From: 0xMosas <tosinolosasa@gmail.com>
Date: Thu, 26 Feb 2026 18:10:03 +0100
Subject: [PATCH 2/2] test: verify zero-fee tipping transfers full amount to
 recipient

Confirm that when fee-basis-points is set to 0, sending a tip
produces only one STX transfer event with the full amount going
to the recipient and no fee transfer to the contract owner.
---
 tests/tipstream.test.ts | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/tests/tipstream.test.ts b/tests/tipstream.test.ts
index 97baea0a..90de67ed 100644
--- a/tests/tipstream.test.ts
+++ b/tests/tipstream.test.ts
@@ -420,6 +420,29 @@ describe("TipStream Contract Tests", () => {
             );
             expect(result).toBeErr(Cl.uint(100));
         });
+
+        it("sending a tip with zero fee transfers full amount to recipient", () => {
+            simnet.callPublicFn(
+                "tipstream",
+                "set-fee-basis-points",
+                [Cl.uint(0)],
+                deployer
+            );
+
+            const { result, events } = simnet.callPublicFn(
+                "tipstream",
+                "send-tip",
+                [Cl.principal(wallet2), Cl.uint(1000000), Cl.stringUtf8("No fee tip")],
+                wallet1
+            );
+
+            expect(result).toBeOk(Cl.uint(0));
+
+            const transfers = events.filter(e => e.event === "stx_transfer_event");
+            expect(transfers).toHaveLength(1);
+            expect(transfers[0].data.amount).toBe("1000000");
+            expect(transfers[0].data.recipient).toBe(wallet2);
+        });
     });
 
     describe("Batch Tipping", () => {