Bump mcp-go to v0.42.0 (#220)

Author: peteski22

NOTICE

@@ -289,9 +289,9 @@ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLI
 
 
 
-## github.com/mark3labs/mcp-go (v0.41.1)
+## github.com/mark3labs/mcp-go (v0.42.0)
 
-License: [MIT](https://github.com/mark3labs/mcp-go/blob/v0.41.1/LICENSE)
+License: [MIT](https://github.com/mark3labs/mcp-go/blob/v0.42.0/LICENSE)
 
 MIT License
 

go.mod

@@ -8,7 +8,7 @@ require (
 	github.com/go-chi/chi/v5 v5.2.3
 	github.com/go-chi/cors v1.2.2
 	github.com/hashicorp/go-hclog v1.6.3
-	github.com/mark3labs/mcp-go v0.41.1
+	github.com/mark3labs/mcp-go v0.42.0
 	github.com/mozilla-ai/mcpd-plugins-sdk-go v0.0.2
 	github.com/spf13/cobra v1.10.1
 	github.com/spf13/pflag v1.0.10

go.sum

@@ -46,8 +46,8 @@ github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
 github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
 github.com/mailru/easyjson v0.9.0 h1:PrnmzHw7262yW8sTBwxi1PdJA3Iw/EKBa8psRf7d9a4=
 github.com/mailru/easyjson v0.9.0/go.mod h1:1+xMtQp2MRNVL/V1bOzuP3aP8VNwRW55fQUto+XFtTU=
-github.com/mark3labs/mcp-go v0.41.1 h1:w78eWfiQam2i8ICL7AL0WFiq7KHNJQ6UB53ZVtH4KGA=
-github.com/mark3labs/mcp-go v0.41.1/go.mod h1:T7tUa2jO6MavG+3P25Oy/jR7iCeJPHImCZHRymCn39g=
+github.com/mark3labs/mcp-go v0.42.0 h1:gk/8nYJh8t3yroCAOBhNbYsM9TCKvkM13I5t5Hfu6Ls=
+github.com/mark3labs/mcp-go v0.42.0/go.mod h1:YnJfOL382MIWDx1kMY+2zsRHU/q78dBg9aFb8W6Thdw=
 github.com/mattn/go-colorable v0.1.9/go.mod h1:u6P/XSegPjTcexA+o6vUJrdnUu04hMope9wVRipJSqc=
 github.com/mattn/go-colorable v0.1.12/go.mod h1:u5H1YNBxpqRaxsYJYSkiCWKzEfiAb1Gb520KVy5xxl4=
 github.com/mattn/go-colorable v0.1.14 h1:9A9LHSqF/7dyVVX6g0U9cwm9pG3kP9gSzcuIPHPsaIE=

internal/api/mcp.go

@@ -1,6 +1,10 @@
 package api
 
-import "github.com/mark3labs/mcp-go/mcp"
+import (
+	"maps"
+
+	"github.com/mark3labs/mcp-go/mcp"
+)
 
 // DomainMeta wraps mcp.Meta for API conversion.
 type DomainMeta mcp.Meta
@@ -13,25 +17,10 @@ type Meta map[string]any
 // Returns empty Meta{} if domain type is nil.
 // See: https://modelcontextprotocol.io/specification/2025-06-18/basic/index#meta
 func (d DomainMeta) ToAPIType() (Meta, error) {
-	if (*mcp.Meta)(&d) == nil {
+	m := (*mcp.Meta)(&d)
+	if m == nil || m.AdditionalFields == nil {
 		return Meta{}, nil
 	}
 
-	// The _meta field is MCP's reserved extensibility mechanism that allows both:
-	// - progressToken: for out-of-band progress notifications (defined by spec)
-	// - Additional fields: custom metadata from servers/clients (extensible)
-	// Both types of fields are merged at the same level in the resulting map.
-	result := make(Meta)
-
-	// Add progressToken if present (using MCP spec-defined field name).
-	if d.ProgressToken != nil {
-		result["progressToken"] = d.ProgressToken
-	}
-
-	// Merge additional fields at the same level.
-	for k, v := range d.AdditionalFields {
-		result[k] = v
-	}
-
-	return result, nil
+	return maps.Clone(m.AdditionalFields), nil
 }

internal/api/resources.go

@@ -296,34 +296,18 @@ func handleServerResourceContent(
 	for _, content := range result.Contents {
 		switch c := content.(type) {
 		case mcp.TextResourceContents:
-			var meta Meta
-			if c.Meta != nil {
-				var err error
-				meta, err = DomainMeta(*c.Meta).ToAPIType()
-				if err != nil {
-					return nil, err
-				}
-			}
 			contents = append(contents, ResourceContent{
 				URI:      c.URI,
 				MIMEType: c.MIMEType,
 				Text:     c.Text,
-				Meta:     meta,
+				Meta:     c.Meta,
 			})
 		case mcp.BlobResourceContents:
-			var meta Meta
-			if c.Meta != nil {
-				var err error
-				meta, err = DomainMeta(*c.Meta).ToAPIType()
-				if err != nil {
-					return nil, err
-				}
-			}
 			contents = append(contents, ResourceContent{
 				URI:      c.URI,
 				MIMEType: c.MIMEType,
 				Blob:     c.Blob,
-				Meta:     meta,
+				Meta:     c.Meta,
 			})
 		}
 	}