diff --git a/cmd/opencodereview/delegate_helpers_test.go b/cmd/opencodereview/delegate_helpers_test.go
index 1e72b3bc5..1247d5dee 100644
--- a/cmd/opencodereview/delegate_helpers_test.go
+++ b/cmd/opencodereview/delegate_helpers_test.go
@@ -6,6 +6,8 @@ package main
 import (
 	"context"
 	"testing"
+
+	"github.com/spf13/cobra"
 )
 
 func TestValidateDelegateOptions(t *testing.T) {
@@ -34,6 +36,42 @@ func TestValidateDelegateOptions(t *testing.T) {
 	}
 }
 
+func TestDelegateFlags_RegisterJSONFormat(t *testing.T) {
+	var opts delegateOptions
+	cmd := &cobra.Command{
+		Use:           "preview",
+		SilenceUsage:  true,
+		SilenceErrors: true,
+		Args:          cobra.NoArgs,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return validateDelegateOptions(&opts)
+		},
+	}
+	registerDelegateFlags(cmd, &opts)
+	cmd.SetArgs([]string{"--format", "json"})
+
+	if err := cmd.Execute(); err != nil {
+		t.Fatalf("delegate preview rejected --format json: %v", err)
+	}
+	if opts.format != "json" {
+		t.Fatalf("format = %q, want json", opts.format)
+	}
+
+	formatFlag := cmd.Flags().Lookup("format")
+	if formatFlag == nil {
+		t.Fatal("delegate preview did not register --format")
+	}
+	if formatFlag.Shorthand != "f" {
+		t.Fatalf("format shorthand = %q, want f", formatFlag.Shorthand)
+	}
+
+	for _, command := range []*cobra.Command{delegatePreviewCmd, delegateRuleCmd} {
+		if command.Flags().Lookup("format") == nil {
+			t.Errorf("%s did not register --format", command.Name())
+		}
+	}
+}
+
 func TestDelegateContextReviewMode(t *testing.T) {
 	cases := []struct {
 		name string
diff --git a/plugins/open-code-review/skills/open-code-review-delegate/SKILL.md b/plugins/open-code-review/skills/open-code-review-delegate/SKILL.md
index ff161f187..d4444569a 100644
--- a/plugins/open-code-review/skills/open-code-review-delegate/SKILL.md
+++ b/plugins/open-code-review/skills/open-code-review-delegate/SKILL.md
@@ -41,6 +41,20 @@ npm install -g @alibaba-group/open-code-review
 
 No LLM configuration is needed for delegation mode.
 
+The delegation JSON workflow requires an OCR CLI release that supports the
+`--format` flag on both `delegate preview` and `delegate rule`. Verify the
+installed binary before starting:
+
+```bash
+ocr delegate preview --help
+```
+
+Continue only when the help output includes `--format` (or `-f`). If the flag
+is missing, the installed CLI is older than this skill's JSON protocol. Upgrade
+OCR to a release that supports delegation JSON output before continuing; do not
+silently fall back to text output because the steps below consume structured
+fields such as `reviewable_files`, `mode`, and `merge_base`.
+
 ## Workflow
 
 ### Step 1: Preview — Determine What to Review
diff --git a/skills/open-code-review-delegate/SKILL.md b/skills/open-code-review-delegate/SKILL.md
index e5bec836e..2276edd27 100644
--- a/skills/open-code-review-delegate/SKILL.md
+++ b/skills/open-code-review-delegate/SKILL.md
@@ -36,6 +36,20 @@ npm install -g @alibaba-group/open-code-review
 
 No LLM configuration is needed for delegation mode.
 
+The delegation JSON workflow requires an OCR CLI release that supports the
+`--format` flag on both `delegate preview` and `delegate rule`. Verify the
+installed binary before starting:
+
+```bash
+ocr delegate preview --help
+```
+
+Continue only when the help output includes `--format` (or `-f`). If the flag
+is missing, the installed CLI is older than this skill's JSON protocol. Upgrade
+OCR to a release that supports delegation JSON output before continuing; do not
+silently fall back to text output because the steps below consume structured
+fields such as `reviewable_files`, `mode`, and `merge_base`.
+
 ## Workflow
 
 ### Step 1: Preview — Determine What to Review