feat: add mcp server (load, unload, export tools + registry)

.github/workflows/code-health-mcp-server.yml

@@ -0,0 +1,68 @@
+name: 'Code Health MCP Server'
+on:
+  push:
+    branches:
+      - main
+    paths: 
+      - 'tools/mcp-server/**'
+      - '.github/workflows/code-health-mcp-server.yml'
+  pull_request:
+    branches:
+      - main
+    paths:
+      - 'tools/mcp-server/**'
+      - '.github/workflows/code-health-mcp-server.yml'
+  workflow_dispatch: {}
+  workflow_call: {}
+
+permissions:
+  contents: read
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - name: Checkout MCP Server
+      uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd
+    - name: Install Go
+      uses: actions/setup-go@4a3601121dd01d1626a1e23e37211e3254c1c06c
+      with:
+        go-version-file: 'tools/mcp-server/go.mod'
+    - name: Build MCP Server
+      working-directory: tools/mcp-server
+      run: make build
+
+  test:
+    needs: build
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd
+      - name: Install Go
+        uses: actions/setup-go@4a3601121dd01d1626a1e23e37211e3254c1c06c
+        with:
+          go-version-file: 'tools/mcp-server/go.mod'
+      - name: Run tests
+        working-directory: tools/mcp-server
+        run: make test
+
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd
+        with:
+          sparse-checkout: |
+            .github
+            tools
+      - name: Install Go
+        uses: actions/setup-go@4a3601121dd01d1626a1e23e37211e3254c1c06c
+        with:
+          go-version-file: 'tools/mcp-server/go.mod'
+          cache: false # see https://github.com/golangci/golangci-lint-action/issues/807
+      - name: golangci-lint
+        uses: golangci/golangci-lint-action@1e7e51e771db61008b38414a730f564565cf7c20
+        with:
+          version: v2.11.4
+          working-directory: tools/mcp-server
+

tools/cli/pkg/openapi/openapi.go

@@ -0,0 +1,47 @@
+// Copyright 2026 MongoDB Inc
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package openapi provides public interfaces for loading and saving OpenAPI specifications.
+// This package wraps the internal openapi package to provide a stable public API.
+package openapi
+
+import (
+	"github.com/mongodb/openapi/tools/cli/internal/openapi"
+	"github.com/oasdiff/kin-openapi/openapi3"
+	"github.com/oasdiff/oasdiff/load"
+	"github.com/spf13/afero"
+)
+
+// Loader provides methods for loading OpenAPI specifications from files.
+type Loader struct {
+	impl *openapi.OpenAPI3
+}
+
+// NewLoader creates a new OpenAPI loader.
+func NewLoader() *Loader {
+	return &Loader{
+		impl: openapi.NewOpenAPI3(),
+	}
+}
+
+// LoadFromPath loads an OpenAPI spec from the given file path.
+func (l *Loader) LoadFromPath(path string) (*load.SpecInfo, error) {
+	return l.impl.CreateOpenAPISpecFromPath(path)
+}
+
+// SaveToFile saves an OpenAPI spec to a file in the specified format.
+// Format can be "json", "yaml", or "all".
+func SaveToFile(path, format string, spec *openapi3.T, fs afero.Fs) error {
+	return openapi.Save(path, spec, format, fs)
+}

tools/go.work

@@ -0,0 +1,6 @@
+go 1.26
+
+use (
+	mcp-server
+	cli
+)

tools/mcp-server/.golangci.yml

@@ -0,0 +1,125 @@
+version: "2"
+run:
+  modules-download-mode: readonly
+  tests: true
+linters:
+  default: none
+  enable:
+    - copyloopvar
+    - dogsled
+    - errcheck
+    - errorlint
+    - exhaustive
+    - funlen
+    - gocritic
+    - godot
+    - goprintffuncname
+    - gosec
+    - govet
+    - ineffassign
+    - lll
+    - makezero
+    - misspell
+    - nakedret
+    - noctx
+    - nolintlint
+    - perfsprint
+    - prealloc
+    - predeclared
+    - revive
+    - rowserrcheck
+    - staticcheck
+    - testifylint
+    - thelper
+    - unconvert
+    - unused
+    - whitespace
+  settings:
+    funlen:
+      lines: 360
+      statements: 120
+    gocritic:
+      enabled-tags:
+        - diagnostic
+        - experimental
+        - opinionated
+        - performance
+        - style
+    govet:
+      enable:
+        - shadow
+    lll:
+      line-length: 150
+    misspell:
+      locale: US
+    nestif:
+      min-complexity: 7
+    revive:
+      severity: warning
+      rules:
+        - name: blank-imports
+        - name: context-as-argument
+        - name: context-keys-type
+        - name: defer
+        - name: dot-imports
+        - name: error-return
+        - name: error-strings
+        - name: error-naming
+        - name: early-return
+        - name: errorf
+        - name: exported
+        - name: import-shadowing
+        - name: indent-error-flow
+        - name: if-return
+        - name: increment-decrement
+        - name: var-naming
+        - name: var-declaration
+        - name: package-comments
+        - name: range
+        - name: receiver-naming
+        - name: time-naming
+        - name: unexported-return
+        - name: indent-error-flow
+        - name: errorf
+        - name: empty-block
+        - name: superfluous-else
+        - name: struct-tag
+        - name: unused-parameter
+        - name: unreachable-code
+        - name: redefines-builtin-id
+        - name: unused-receiver
+        - name: constant-logical-expr
+        - name: confusing-naming
+        - name: unnecessary-stmt
+        - name: use-any
+        - name: imports-blocklist
+          arguments:
+            - github.com/pkg/errors
+  exclusions:
+    generated: lax
+    presets:
+      - comments
+      - common-false-positives
+      - legacy
+      - std-error-handling
+    paths:
+      - third_party$
+      - builtin$
+      - examples$
+formatters:
+  enable:
+    - gci
+    - gofmt
+    - goimports
+  settings:
+    gci:
+      sections:
+        - standard
+        - default
+  exclusions:
+    generated: lax
+    paths:
+      - third_party$
+      - builtin$
+      - examples$
+

tools/mcp-server/Makefile

@@ -0,0 +1,46 @@
+.PHONY: build
+build: ## Build the MCP server binary
+	@echo "==> Building mcp-server binary"
+	go build -o bin/mcp-server ./cmd
+
+.PHONY: install
+install: ## Install the MCP server binary to GOPATH/bin
+	@echo "==> Installing mcp-server"
+	go install ./cmd
+
+##@ Development
+
+.PHONY: fmt
+fmt: ## Format Go code
+	@echo "==> Formatting code"
+	gofmt -w -s .
+
+.PHONY: lint
+lint: ## Run linter
+	@echo "==> Running linter"
+	golangci-lint run
+
+.PHONY: test
+test: ## Run tests
+	@echo "==> Running tests"
+	go test -v ./...
+
+##@ Cleanup
+
+.PHONY: clean
+clean: ## Remove build artifacts
+	@echo "==> Cleaning build artifacts"
+	rm -rf bin/
+
+##@ Dependencies
+
+.PHONY: deps
+deps: ## Download dependencies
+	@echo "==> Downloading dependencies"
+	go mod download
+
+.PHONY: tidy
+tidy: ## Tidy go.mod
+	@echo "==> Tidying go.mod"
+	go mod tidy
+

tools/mcp-server/cmd/main.go

@@ -0,0 +1,46 @@
+package main
+
+import (
+	"context"
+	"log"
+	"os"
+
+	"github.com/modelcontextprotocol/go-sdk/mcp"
+	"github.com/mongodb/openapi/tools/mcp-server/internal/registry"
+	"github.com/mongodb/openapi/tools/mcp-server/internal/tools"
+)
+
+const (
+	serverName    = "openapi-mcp-server"
+	serverVersion = "0.1.0"
+)
+
+func main() {
+	if err := run(); err != nil {
+		log.Fatalf("Error: %v", err)
+	}
+}
+
+func run() error {
+	reg := registry.New()
+
+	impl := &mcp.Implementation{
+		Name:    serverName,
+		Version: serverVersion,
+	}
+	server := mcp.NewServer(impl, nil)
+
+	tools.Register(server, reg)
+
+	// Log to stderr (stdout is reserved for MCP protocol)
+	log.SetOutput(os.Stderr)
+	log.Printf("Starting %s v%s", serverName, serverVersion)
+
+	transport := &mcp.StdioTransport{}
+	session, err := server.Connect(context.Background(), transport, nil)
+	if err != nil {
+		return err
+	}
+
+	return session.Wait()
+}

tools/mcp-server/go.mod

@@ -0,0 +1,43 @@
+module github.com/mongodb/openapi/tools/mcp-server
+
+go 1.26
+
+require (
+	github.com/modelcontextprotocol/go-sdk v1.5.0
+	github.com/mongodb/openapi/tools/cli v0.0.0
+	github.com/oasdiff/kin-openapi v0.136.4
+	github.com/spf13/afero v1.15.0
+)
+
+require (
+	cloud.google.com/go v0.123.0 // indirect
+	github.com/go-openapi/jsonpointer v0.22.5 // indirect
+	github.com/go-openapi/swag/jsonname v0.25.5 // indirect
+	github.com/google/jsonschema-go v0.4.2 // indirect
+	github.com/iancoleman/strcase v0.3.0 // indirect
+	github.com/josharian/intern v1.0.0 // indirect
+	github.com/kr/text v0.2.0 // indirect
+	github.com/mailru/easyjson v0.9.2 // indirect
+	github.com/mohae/deepcopy v0.0.0-20170929034955-c48cc78d4826 // indirect
+	github.com/oasdiff/oasdiff v1.12.7 // indirect
+	github.com/oasdiff/yaml v0.0.4 // indirect
+	github.com/oasdiff/yaml3 v0.0.4 // indirect
+	github.com/perimeterx/marshmallow v1.1.5 // indirect
+	github.com/segmentio/asm v1.1.3 // indirect
+	github.com/segmentio/encoding v0.5.4 // indirect
+	github.com/tidwall/gjson v1.18.0 // indirect
+	github.com/tidwall/match v1.2.0 // indirect
+	github.com/tidwall/pretty v1.2.1 // indirect
+	github.com/tidwall/sjson v1.2.5 // indirect
+	github.com/wI2L/jsondiff v0.7.0 // indirect
+	github.com/woodsbury/decimal128 v1.4.0 // indirect
+	github.com/yargevad/filepathx v1.0.0 // indirect
+	github.com/yosida95/uritemplate/v3 v3.0.2 // indirect
+	go.uber.org/mock v0.6.0 // indirect
+	golang.org/x/oauth2 v0.35.0 // indirect
+	golang.org/x/sys v0.42.0 // indirect
+	golang.org/x/text v0.35.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)
+
+replace github.com/mongodb/openapi/tools/cli => ../cli