chore: Release server.json schema version 2025-12-11 (#841)

Prepared by Claude Code, iterated and reviewed by me.

## Summary

This PR releases the server.json schema version `2025-12-11`,
incorporating URL template variables for remote servers from #570.

### What's New

- **URL Template Variables for Remote Servers** - Remote servers can now
define configurable variables in URLs using `{curly_braces}` notation,
enabling multi-tenant deployments.

### Schema Version
- `2025-10-17` → `2025-12-11`

## Release Sequence

1. ~~**First: Merge static repo PR** -
modelcontextprotocol/static#11 (publishes schema
to versioned URL)~~
2. **Then: Merge this PR** - Updates registry code to reference the new
schema version

## Changes in This PR

- [x] Update CHANGELOG.md with release notes
- [x] Update `CurrentSchemaVersion` in `pkg/model/constants.go`
- [x] Update schema example URL in `docs/reference/api/openapi.yaml`
- [x] Update schema URL in `pkg/api/v0/types.go`
- [x] Update all documentation examples to use new schema version
- [x] Regenerate `server.schema.json`

## Test Plan
- [x] `make check` passes (lint, schema validation, example validation)
- [x] Unit tests pass for validators and publisher commands

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Opus 4.5 <[email protected]>

Author: tadasant

cmd/publisher/commands/publish_test.go

@@ -44,8 +44,8 @@ func TestPublishCommand_DeprecatedSchema(t *testing.T) {
 			errorSubstr: "deprecated schema detected",
 		},
 		{
-			name:        "current 2025-10-17 schema should pass validation",
-			schema:      "https://static.modelcontextprotocol.io/schemas/2025-10-17/server.schema.json",
+			name:        "current 2025-12-11 schema should pass validation",
+			schema:      "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json",
 			expectError: false,
 		},
 		{

data/seed.json

@@ -1,6 +1,6 @@
 [
   {
-    "$schema": "https://static.modelcontextprotocol.io/schemas/2025-10-17/server.schema.json",
+    "$schema": "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json",
     "name": "io.github.domdomegg/airtable-mcp-server",
     "description": "Read and write access to Airtable database schemas, tables, and records.",
     "repository": {
@@ -62,7 +62,7 @@
     ]
   },
   {
-    "$schema": "https://static.modelcontextprotocol.io/schemas/2025-10-17/server.schema.json",
+    "$schema": "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json",
     "name": "io.github.domdomegg/airtable-mcp-server",
     "description": "Read and write access to Airtable database schemas, tables, and records.",
     "repository": {
@@ -115,7 +115,7 @@
     ]
   },
   {
-    "$schema": "https://static.modelcontextprotocol.io/schemas/2025-10-17/server.schema.json",
+    "$schema": "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json",
     "name": "io.github.domdomegg/time-mcp-nuget",
     "description": "Get the current UTC time in RFC 3339 format.",
     "repository": {
@@ -136,7 +136,7 @@
     ]
   },
   {
-    "$schema": "https://static.modelcontextprotocol.io/schemas/2025-10-17/server.schema.json",
+    "$schema": "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json",
     "name": "io.github.domdomegg/time-mcp-pypi",
     "description": "Get the current UTC time in RFC 3339 format.",
     "repository": {

docs/modelcontextprotocol-io/package-types.mdx

@@ -15,7 +15,7 @@ npm packages use `"registryType": "npm"` in `server.json`. For example:
 
 ```json server.json highlight={9}
 {
-  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-10-17/server.schema.json",
+  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json",
   "name": "io.github.username/email-integration-mcp",
   "title": "Email Integration",
   "description": "Send emails and manage email accounts",
@@ -53,7 +53,7 @@ PyPI packages use `"registryType": "pypi"` in `server.json`. For example:
 
 ```json server.json highlight={9}
 {
-  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-10-17/server.schema.json",
+  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json",
   "name": "io.github.username/database-query-mcp",
   "title": "Database Query",
   "description": "Execute SQL queries and manage database connections",
@@ -91,7 +91,7 @@ NuGet packages use `"registryType": "nuget"` in `server.json`. For example:
 
 ```json server.json highlight={9}
 {
-  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-10-17/server.schema.json",
+  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json",
   "name": "io.github.username/azure-devops-mcp",
   "title": "Azure DevOps",
   "description": "Manage Azure DevOps work items and pipelines",
@@ -135,7 +135,7 @@ Docker/OCI images use `"registryType": "oci"` in `server.json`. For example:
 
 ```json server.json highlight={9}
 {
-  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-10-17/server.schema.json",
+  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json",
   "name": "io.github.username/kubernetes-manager-mcp",
   "title": "Kubernetes Manager",
   "description": "Deploy and manage Kubernetes resources",
@@ -170,7 +170,7 @@ MCPB packages use `"registryType": "mcpb"` in `server.json`. For example:
 
 ```json server.json highlight={9}
 {
-  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-10-17/server.schema.json",
+  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json",
   "name": "io.github.username/image-processor-mcp",
   "title": "Image Processor",
   "description": "Process and transform images with various filters",

docs/modelcontextprotocol-io/quickstart.mdx

@@ -143,7 +143,7 @@ Open the generated `server.json` file, and you should see contents like:
 
 ```json server.json
 {
-  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-10-17/server.schema.json",
+  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json",
   "name": "io.github.my-username/weather",
   "description": "An MCP server for weather information.",
   "repository": {
@@ -177,7 +177,7 @@ Edit the contents as necessary:
 
 ```diff server.json
  {
-   "$schema": "https://static.modelcontextprotocol.io/schemas/2025-10-17/server.schema.json",
+   "$schema": "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json",
    "name": "io.github.my-username/weather",
    "description": "An MCP server for weather information.",
    "repository": {

docs/modelcontextprotocol-io/registry-aggregators.mdx

@@ -75,7 +75,7 @@ The subregistry OpenAPI spec allows subregistries to inject custom metadata via
 
 ```json server.json highlight={17-26}
 {
-  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-10-17/server.schema.json",
+  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json",
   "name": "io.github.username/email-integration-mcp",
   "title": "Email Integration",
   "description": "Send emails and manage email accounts",

docs/modelcontextprotocol-io/remote-servers.mdx

@@ -7,7 +7,7 @@ The MCP Registry supports remote MCP servers via the `remotes` property in `serv
 
 ```json server.json highlight={7-12}
 {
-  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-10-17/server.schema.json",
+  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json",
   "name": "com.example/acme-analytics",
   "title": "ACME Analytics",
   "description": "Real-time business intelligence and reporting platform",
@@ -31,7 +31,7 @@ Specify the transport by setting the `type` property of the `remotes` entry to e
 
 ```json server.json highlight={9,13}
 {
-  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-10-17/server.schema.json",
+  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json",
   "name": "com.example/acme-analytics",
   "title": "ACME Analytics",
   "description": "Real-time business intelligence and reporting platform",
@@ -49,13 +49,71 @@ Specify the transport by setting the `type` property of the `remotes` entry to e
 }
 ```
 
+## URL Template Variables
+
+Remote servers can define URL template variables using `{curly_braces}` notation. This enables multi-tenant deployments where a single server definition can support multiple endpoints with configurable values:
+
+```json server.json highlight={10-17}
+{
+  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json",
+  "name": "com.example/acme-analytics",
+  "title": "ACME Analytics",
+  "description": "Real-time business intelligence and reporting platform",
+  "version": "2.0.0",
+  "remotes": [
+    {
+      "type": "streamable-http",
+      "url": "https://{tenant_id}.analytics.example.com/mcp",
+      "variables": {
+        "tenant_id": {
+          "description": "Your tenant identifier (e.g., 'us-cell1', 'emea-cell1')",
+          "isRequired": true
+        }
+      }
+    }
+  ]
+}
+```
+
+When configuring this server, users provide their `tenant_id` value, and the URL template gets resolved to the appropriate endpoint (e.g., `https://us-cell1.analytics.example.com/mcp`).
+
+Variables support additional properties like `default`, `choices`, and `isSecret`:
+
+```json server.json highlight={12-22}
+{
+  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json",
+  "name": "com.example/multi-region-mcp",
+  "title": "Multi-Region MCP",
+  "description": "MCP server with regional endpoints",
+  "version": "1.0.0",
+  "remotes": [
+    {
+      "type": "streamable-http",
+      "url": "https://api.example.com/{region}/mcp",
+      "variables": {
+        "region": {
+          "description": "Deployment region",
+          "isRequired": true,
+          "choices": [
+            "us-east-1",
+            "eu-west-1",
+            "ap-southeast-1"
+          ],
+          "default": "us-east-1"
+        }
+      }
+    }
+  ]
+}
+```
+
 ## HTTP Headers
 
 MCP clients can be instructed to send specific HTTP headers by adding the `headers` property to the `remotes` entry:
 
 ```json server.json highlight={11-18}
 {
-  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-10-17/server.schema.json",
+  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json",
   "name": "com.example/acme-analytics",
   "title": "ACME Analytics",
   "description": "Real-time business intelligence and reporting platform",
@@ -83,7 +141,7 @@ The `remotes` property can coexist with the `packages` property in `server.json`
 
 ```json server.json highlight={7-22}
 {
-  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-10-17/server.schema.json",
+  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json",
   "name": "io.github.username/email-integration-mcp",
   "title": "Email Integration",
   "description": "Send emails and manage email accounts",

docs/modelcontextprotocol-io/versioning.mdx

@@ -7,7 +7,7 @@ MCP servers **MUST** define a version string in `server.json`. For example:
 
 ```json server.json highlight={6}
 {
-  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-10-17/server.schema.json",
+  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json",
   "name": "io.github.username/email-integration-mcp",
   "title": "Email Integration",
   "description": "Send emails and manage email accounts",

docs/reference/api/openapi.yaml

@@ -728,7 +728,7 @@ components:
           type: string
           format: uri
           description: JSON Schema URI for this server.json format
-          example: "https://static.modelcontextprotocol.io/schemas/draft/server.schema.json"
+          example: "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json"
         packages:
           type: array
           items:

docs/reference/server-json/CHANGELOG.md

@@ -16,6 +16,34 @@ When ready for release, changes in this section will be moved to a dated version
 
 ---
 
+## 2025-12-11
+
+### Changed
+
+#### URL Template Variables for Remote Servers ([#570](https://github.com/modelcontextprotocol/registry/pull/570))
+
+Remote servers can now define URL template variables using `{curly_braces}` notation. This enables multi-tenant deployments where a single server definition can support multiple endpoints with configurable values.
+
+**Example:**
+```json
+{
+  "remotes": [{
+    "type": "streamable-http",
+    "url": "https://{tenant_id}.api.example.com/mcp",
+    "variables": {
+      "tenant_id": {
+        "description": "Your tenant identifier",
+        "isRequired": true
+      }
+    }
+  }]
+}
+```
+
+**Migration:** No changes required. Existing servers continue to work unchanged.
+
+---
+
 ## 2025-10-17
 
 ### Changed