Convert between YAML and JSON (parse k8s/CI configs, multi-doc streams) via @mukundakatta/yaml-mcp (npx)

Recipe: YAML ↔ JSON via @mukundakatta/yaml-mcp

Install & launch:

npm install @mukundakatta/yaml-mcp
# Server entry: node node_modules/@mukundakatta/yaml-mcp/index.js
# Transport: stdio

Tools (2):

Optional params: to_json accepts all_documents: true for multi-doc YAML streams. to_yaml accepts indent: <int> (default 2).

Example 1 — Parse a Kubernetes Service manifest:

// Request
{ "method": "tools/call", "params": { "name": "to_json", "arguments": { "text": "apiVersion: v1\nkind: Service\nmetadata:\n  name: my-app\n  labels:\n    app: web\n    tier: frontend\nspec:\n  selector:\n    app: web\n  ports:\n    - port: 80\n      targetPort: 8080\n      protocol: TCP\n  type: LoadBalancer" } } }

// Response (5ms)
{ "content": [{ "type": "text", "text": "{\"value\":{\"apiVersion\":\"v1\",\"kind\":\"Service\",\"metadata\":{\"name\":\"my-app\",\"labels\":{\"app\":\"web\",\"tier\":\"frontend\"}},\"spec\":{\"selector\":{\"app\":\"web\"},\"ports\":[{\"port\":80,\"targetPort\":8080,\"protocol\":\"TCP\"}],\"type\":\"LoadBalancer\"}}}" }] }

Example 2 — Serialize a DB config to YAML:

// Request
{ "method": "tools/call", "params": { "name": "to_yaml", "arguments": { "value": {"database":{"host":"localhost","port":5432,"name":"mydb","credentials":{"user":"admin","password":"secret"},"options":{"ssl":true,"pool_size":10}}} } } }

// Response (1ms)
{ "content": [{ "type": "text", "text": "database:\n  host: localhost\n  port: 5432\n  name: mydb\n  credentials:\n    user: admin\n    password: secret\n  options:\n    ssl: true\n    pool_size: 10\n" }] }

Example 3 — Multi-document YAML stream:

// Request
{ "method": "tools/call", "params": { "name": "to_json", "arguments": { "text": "---\nname: doc1\nversion: 1\n---\nname: doc2\nversion: 2", "all_documents": true } } }

// Response (0ms)
{ "content": [{ "type": "text", "text": "{\"value\":[{\"name\":\"doc1\",\"version\":1},{\"name\":\"doc2\",\"version\":2}]}" }] }

Performance: sub-5ms per call. Server startup ~200ms cold.

When to use: parsing k8s manifests, docker-compose.yml, GitHub Actions workflows, Ansible playbooks, or any YAML config into JSON for programmatic access. Also: generating YAML from structured data for CI templates.