From 328a25d503562bfc89037e98e08fddfc0073dfc2 Mon Sep 17 00:00:00 2001
From: Martin Emde <martinemde@users.noreply.github.com>
Date: Fri, 4 Jul 2025 11:35:33 -0700
Subject: [PATCH] mcp: ensure meta is not skipped on blob ResourceContents
 (#96)

I noticed this while working on #95. Seems Meta was accidentally skipped
in the custom wire format struct.
---
 mcp/content.go      | 2 ++
 mcp/content_test.go | 4 ++++
 2 files changed, 6 insertions(+)

diff --git a/mcp/content.go b/mcp/content.go
index 61111a9..fd027cf 100644
--- a/mcp/content.go
+++ b/mcp/content.go
@@ -187,10 +187,12 @@ func (r ResourceContents) MarshalJSON() ([]byte, error) {
 		URI      string `json:"uri,omitempty"`
 		MIMEType string `json:"mimeType,omitempty"`
 		Blob     []byte `json:"blob"`
+		Meta     Meta   `json:"_meta,omitempty"`
 	}{
 		URI:      r.URI,
 		MIMEType: r.MIMEType,
 		Blob:     r.Blob,
+		Meta:     r.Meta,
 	}
 	return json.Marshal(br)
 }
diff --git a/mcp/content_test.go b/mcp/content_test.go
index 8c4e530..7a549be 100644
--- a/mcp/content_test.go
+++ b/mcp/content_test.go
@@ -154,6 +154,10 @@ func TestEmbeddedResource(t *testing.T) {
 			&mcp.ResourceContents{URI: "u", Blob: []byte{1}},
 			`{"uri":"u","blob":"AQ=="}`,
 		},
+		{
+			&mcp.ResourceContents{URI: "u", MIMEType: "m", Blob: []byte{1}, Meta: mcp.Meta{"key": "value"}},
+			`{"uri":"u","mimeType":"m","blob":"AQ==","_meta":{"key":"value"}}`,
+		},
 	} {
 		data, err := json.Marshal(tt.rc)
 		if err != nil {