PQM.guide

A community-driven Power Query M language reference, hosted at pqm.guide.

PQM.guide documents 512 Power Query M functions across 24 categories with clear syntax references, visual output examples, and practical best practices. It also includes concept guides, practical patterns, and an MCP server so AI assistants can query M documentation directly. Think of it as DAX.guide for the M language.

What's on the Site

Section	URL	Description
Functions	/functions/[slug]	512 functions across 24 categories with syntax, parameters, examples, and best practices
Concepts	/concepts/[slug]	17 concept guides covering M fundamentals (lazy evaluation, query folding, type system, etc.)
Patterns	/patterns/[slug]	18 practical M recipes grouped by difficulty (beginner → advanced)
Start Here	/learn	A curated 8-step learning path for developers new to M
Sample Tables	/sample-tables	Reference data used in function examples (Sales, Customers, Products, Employees, OrderLog)
Resources	/resources	Curated tools, books, YouTube channels, blogs, and community links
MCP Server	/mcp	Connect AI assistants like Claude and Cursor to PQM.guide via the Model Context Protocol

API & LLM Access

PQM.guide exposes several machine-readable endpoints:

Endpoint	Description
GET /api/functions	All 512 functions (metadata)
GET /api/functions/[slug]	Single function with full content, remarks, and parsed examples
GET /api/concepts	All concept guides
GET /api/concepts/[slug]	Single concept with full content
GET /api/patterns	All patterns
GET /api/patterns/[slug]	Single pattern with full content
GET /api/search?q=	Fuzzy search across all functions
GET /api/tables/[id]	Sample table data as JSON (Sales, Customers, Products, Employees, OrderLog)
GET /llms.txt	Plain-text index (llmstxt.org format) for LLM crawlers
POST /api/mcp	MCP JSON-RPC 2.0 endpoint (Streamable HTTP transport)

MCP Server

Connect Claude Desktop by adding this to claude_desktop_config.json:

{
  "mcpServers": {
    "pqm-guide": {
      "command": "npx",
      "args": ["mcp-remote", "https://pqm.guide/api/mcp"]
    }
  }
}

Any client supporting Streamable HTTP can also connect directly to https://pqm.guide/api/mcp.

Contributing

PQM.guide is open to contributions from the Power Query community. All content lives in MDX files — no special build knowledge required for most edits.

Quick edits (typos, wording, examples)

1. Fork this repository
2. Find the file you want to edit:
   • Functions: src/content/functions/[slug].mdx
   • Concepts: src/content/concepts/[slug].mdx
   • Patterns: src/content/patterns/[slug].mdx
3. Make your changes and submit a pull request

Adding a new function page

Function pages are MDX files in src/content/functions/ with YAML frontmatter. Use any existing file as a template.

File naming: category-functionname.mdx in lowercase (e.g., text-contains.mdx)

Rules:

• Examples must use the shared sample tables (Sales, Customers, Products, Employees, OrderLog) — never Table.FromRecords for sample data
• Wrap expected output in <!--output ... --> HTML comments as JSON with columns and rows
• See the Sample Tables page for available data

Adding a new concept guide

Concept guides live in src/content/concepts/. Use any existing concept as a template.

Frontmatter:

---
title: "Your Concept Title"
slug: "your-concept-slug"
description: "One sentence description shown in listings and meta tags."
relatedConcepts:
  - "other-concept-slug"
relatedFunctions:
  - "function-slug"
---

Body is standard Markdown with fenced code blocks using the powerquery language identifier.

Adding a new pattern

Patterns live in src/content/patterns/. Use any existing pattern as a template.

Frontmatter:

---
title: "Pattern Title"
slug: "pattern-slug"
description: "One sentence description."
difficulty: "beginner"   # beginner | intermediate | advanced
relatedFunctions:
  - "function-slug"
relatedConcepts:
  - "concept-slug"
---

Patterns should follow a problem → solution → explanation structure with working code examples.

Suggesting changes without code

• Open an issue to report errors or suggest improvements
• Start a discussion to propose new content or features

Running Locally

npm install
npm run dev

Open http://localhost:3000 to preview the site. New MDX content is picked up automatically — restart the dev server if a brand-new content directory isn't appearing.

Tech Stack

• Next.js 16 with App Router
• React 19
• Tailwind CSS 4
• TypeScript, MDX, gray-matter, PrismJS, Fuse.js, next-themes
• @fluentui/react-icons for sidebar category icons
• MCP: JSON-RPC 2.0 over Streamable HTTP (no external SDK)
• Deployed on Vercel