diff --git a/go.mod b/go.mod
index 25e319aefeb..faf89bb607c 100644
--- a/go.mod
+++ b/go.mod
@@ -12,7 +12,7 @@ require (
 	gitea.com/go-chi/session v0.0.0-20251124165456-68e0254e989e
 	gitea.com/lunny/dingtalk_webhook v0.0.0-20171025031554-e3534c89ef96
 	gitea.com/lunny/levelqueue v0.4.2-0.20230414023320-3c0159fe0fe4
-	gitea.dev/actions-proto-go v0.5.0
+	gitea.dev/actions-proto-go v0.6.0
 	gitea.dev/sdk v1.0.1
 	github.com/42wim/httpsig v1.2.4
 	github.com/42wim/sshsig v0.0.0-20260317195500-b9f38cf0d432
diff --git a/go.sum b/go.sum
index 687b2458812..aff785fe47a 100644
--- a/go.sum
+++ b/go.sum
@@ -26,8 +26,8 @@ gitea.com/lunny/levelqueue v0.4.2-0.20230414023320-3c0159fe0fe4 h1:IFT+hup2xejHq
 gitea.com/lunny/levelqueue v0.4.2-0.20230414023320-3c0159fe0fe4/go.mod h1:HBqmLbz56JWpfEGG0prskAV97ATNRoj5LDmPicD22hU=
 gitea.com/xorm/sqlfiddle v0.0.0-20180821085327-62ce714f951a h1:lSA0F4e9A2NcQSqGqTOXqu2aRi/XEQxDCBwM8yJtE6s=
 gitea.com/xorm/sqlfiddle v0.0.0-20180821085327-62ce714f951a/go.mod h1:EXuID2Zs0pAQhH8yz+DNjUbjppKQzKFAn28TMYPB6IU=
-gitea.dev/actions-proto-go v0.5.0 h1:Fc3DI4Fm3B3JBRXFUjegql+usoNAjjAw1cxMansfA2I=
-gitea.dev/actions-proto-go v0.5.0/go.mod h1:p4RX+D9oqiEEzzkPMXscw2CmaGuYFPWFc6xIOmDNDqs=
+gitea.dev/actions-proto-go v0.6.0 h1:gjllYQ5vmwlkqOeofTQu5qKTZpmf7kWsafoHvoPCSzY=
+gitea.dev/actions-proto-go v0.6.0/go.mod h1:p4RX+D9oqiEEzzkPMXscw2CmaGuYFPWFc6xIOmDNDqs=
 gitea.dev/sdk v1.0.1 h1:CWXQUQvp2I6YKOWkhYo1Flx2sRNfMK1X9Op4oR2awXs=
 gitea.dev/sdk v1.0.1/go.mod h1:jCf5Uzz0Jkb61jxNgMxLOCWwle1J1B2nKdcRtxuK9rY=
 github.com/42wim/httpsig v1.2.4 h1:mI5bH0nm4xn7K18fo1K3okNDRq8CCJ0KbBYWyA6r8lU=
diff --git a/routers/api/actions/runner/runner.go b/routers/api/actions/runner/runner.go
index 803b7c13a12..012f875ec70 100644
--- a/routers/api/actions/runner/runner.go
+++ b/routers/api/actions/runner/runner.go
@@ -69,7 +69,7 @@ func (s *Service) Register(
 	}
 
 	labels := req.Msg.Labels
-	hasCancellingSupport, _ := runnerRequestHasCancellingCapability(req.Msg)
+	hasCancellingSupport := slices.Contains(req.Msg.GetCapabilities(), runnerCapabilityCancelling)
 
 	// create new runner
 	name := util.EllipsisDisplayString(req.Msg.Name, 255)
@@ -116,26 +116,11 @@ func (s *Service) Register(
 // state and will run post-step cleanup before finalizing the task.
 const runnerCapabilityCancelling = "cancelling"
 
-type capabilityGetter interface {
-	GetCapabilities() []string
-}
-
 type declareRequest interface {
 	proto.Message
 	GetVersion() string
 	GetLabels() []string
-}
-
-func runnerRequestHasCancellingCapability(req proto.Message) (bool, bool) {
-	if req == nil {
-		return false, false
-	}
-
-	if typedReq, ok := any(req).(capabilityGetter); ok {
-		return slices.Contains(typedReq.GetCapabilities(), runnerCapabilityCancelling), true
-	}
-
-	return false, false
+	GetCapabilities() []string
 }
 
 func applyDeclareRequestToRunner(runner *actions_model.ActionRunner, req declareRequest) []string {
@@ -143,8 +128,8 @@ func applyDeclareRequestToRunner(runner *actions_model.ActionRunner, req declare
 	runner.Version = req.GetVersion()
 
 	cols := []string{"agent_labels", "version"}
-	hasCancellingSupport, capabilityStateKnown := runnerRequestHasCancellingCapability(req)
-	if capabilityStateKnown && runner.HasCancellingSupport != hasCancellingSupport {
+	hasCancellingSupport := slices.Contains(req.GetCapabilities(), runnerCapabilityCancelling)
+	if runner.HasCancellingSupport != hasCancellingSupport {
 		runner.HasCancellingSupport = hasCancellingSupport
 		cols = append(cols, "has_cancelling_support")
 	}
diff --git a/routers/api/actions/runner/runner_test.go b/routers/api/actions/runner/runner_test.go
index b2ed9290878..8a38ac70a23 100644
--- a/routers/api/actions/runner/runner_test.go
+++ b/routers/api/actions/runner/runner_test.go
@@ -12,47 +12,22 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-type capabilityRegisterRequest struct {
-	*runnerv1.RegisterRequest
-	capabilities []string
-}
-
-func (r *capabilityRegisterRequest) GetCapabilities() []string {
-	return r.capabilities
-}
-
-type capabilityDeclareRequest struct {
-	*runnerv1.DeclareRequest
-	capabilities []string
-}
-
-func (r *capabilityDeclareRequest) GetCapabilities() []string {
-	return r.capabilities
-}
-
-func TestRunnerRequestHasCancellingCapabilityTypedAccessor(t *testing.T) {
-	registerReq := &capabilityRegisterRequest{
-		RegisterRequest: &runnerv1.RegisterRequest{},
-		capabilities:    []string{runnerCapabilityCancelling, "other"},
+func TestApplyDeclareRequestToRunnerAdvertisedCapabilityEnablesCancelling(t *testing.T) {
+	runner := &actions_model.ActionRunner{}
+	req := &runnerv1.DeclareRequest{
+		Version:      "1.2.3",
+		Labels:       []string{"linux"},
+		Capabilities: []string{runnerCapabilityCancelling, "other"},
 	}
-	hasCapability, known := runnerRequestHasCancellingCapability(registerReq)
-	assert.True(t, hasCapability)
-	assert.True(t, known)
 
-	declareReq := &capabilityDeclareRequest{
-		DeclareRequest: &runnerv1.DeclareRequest{},
-		capabilities:   nil,
-	}
-	hasCapability, known = runnerRequestHasCancellingCapability(declareReq)
-	assert.False(t, hasCapability)
-	assert.True(t, known)
-
-	hasCapability, known = runnerRequestHasCancellingCapability(nil)
-	assert.False(t, hasCapability)
-	assert.False(t, known)
+	cols := applyDeclareRequestToRunner(runner, req)
+	assert.Equal(t, []string{"agent_labels", "version", "has_cancelling_support"}, cols)
+	assert.True(t, runner.HasCancellingSupport)
+	assert.Equal(t, "1.2.3", runner.Version)
+	assert.Equal(t, []string{"linux"}, runner.AgentLabels)
 }
 
-func TestApplyDeclareRequestToRunnerPreservesUnknownCapabilityState(t *testing.T) {
+func TestApplyDeclareRequestToRunnerMissingCapabilityDisablesCancelling(t *testing.T) {
 	runner := &actions_model.ActionRunner{
 		HasCancellingSupport: true,
 	}
@@ -61,26 +36,22 @@ func TestApplyDeclareRequestToRunnerPreservesUnknownCapabilityState(t *testing.T
 		Labels:  []string{"linux"},
 	}
 
-	cols := applyDeclareRequestToRunner(runner, req)
-	assert.Equal(t, []string{"agent_labels", "version"}, cols)
-	assert.True(t, runner.HasCancellingSupport)
-	assert.Equal(t, "1.2.3", runner.Version)
-	assert.Equal(t, []string{"linux"}, runner.AgentLabels)
-}
-
-func TestApplyDeclareRequestToRunnerUpdatesTypedCapabilityState(t *testing.T) {
-	runner := &actions_model.ActionRunner{
-		HasCancellingSupport: true,
-	}
-	req := &capabilityDeclareRequest{
-		DeclareRequest: &runnerv1.DeclareRequest{
-			Version: "1.2.3",
-			Labels:  []string{"linux"},
-		},
-		capabilities: []string{},
-	}
-
 	cols := applyDeclareRequestToRunner(runner, req)
 	assert.Equal(t, []string{"agent_labels", "version", "has_cancelling_support"}, cols)
 	assert.False(t, runner.HasCancellingSupport)
 }
+
+func TestApplyDeclareRequestToRunnerUnchangedCapabilityOmitsColumn(t *testing.T) {
+	runner := &actions_model.ActionRunner{
+		HasCancellingSupport: true,
+	}
+	req := &runnerv1.DeclareRequest{
+		Version:      "1.2.3",
+		Labels:       []string{"linux"},
+		Capabilities: []string{runnerCapabilityCancelling},
+	}
+
+	cols := applyDeclareRequestToRunner(runner, req)
+	assert.Equal(t, []string{"agent_labels", "version"}, cols)
+	assert.True(t, runner.HasCancellingSupport)
+}