#claude

How to Add an MCP Server to Claude Desktop (2026)

The exact claude_desktop_config.json setup to connect a local MCP server to Claude Desktop, verify it with the MCP Inspector, and fix a server that will not show up.

LLM as a Judge: Score AI Agent Outputs with Claude (2026)

A minimal, framework-free LLM-as-a-judge harness in Python on Claude: rubric design, pointwise and pairwise scoring, and fixes for position, verbosity, and self-preference bias.

How to Build an MCP Server in Python with FastMCP (2026)

A runnable 2026 tutorial: build a write-capable MCP server in Python with FastMCP and the official MCP SDK. Add tools with @mcp.tool(), back them with SQLite, test in the Inspector, and connect it to Claude for Desktop.

Run Claude Tool Calls in Parallel (TypeScript, 2026)

Speed up your Claude agent loop by running independent tool calls concurrently in TypeScript. Copy-paste code for parallel tool_use, is_error handling, and disable_parallel_tool_use.

Cancel an In-Flight Claude Tool Call From the Browser

Wire AbortController from the browser into the Claude stream and your tools, cancel a run even after a reload, and clean up partial side effects safely.

Persist Claude tool-call results across page reloads in Next.js (June 2026)

Resume Claude streams across browser reload with Last-Event-ID (June 2026)

Make a Claude turn survive a browser reload: server-side ring buffer keyed by message.id, the WHATWG Last-Event-ID header, and a Next.js App Router Route Handler that replays missed SSE frames in 180 ms. Measured June 2026 on claude-sonnet-4-6.

Relay Claude SSE to the browser in Next.js (June 2026)

A copy-paste Next.js App Router pattern that relays Claude's Messages-API SSE events to the browser via a Route Handler and a fetch+ReadableStream client. Includes the runtime, headers, and disconnect handling that work around the legacy pages/api flushing bug documented in Vercel Discussion #48427. Measured first-token latency: 480 ms; cost approximately $0.0041 per turn with claude-sonnet-4-6 at June 2026 pricing.

Stream Claude tool calls in a TypeScript agent loop (June 2026)

A complete TypeScript tutorial for the streaming agent loop on Claude: input_json_delta accumulation, multi-turn dispatch, AbortController cancellation, and the eager_input_streaming workaround for the verified 5 second first-content delay on tool use. About $0.03 per call with claude-sonnet-4-6 at June 2026 pricing.

How to Build an MCP Server (2026): Your First Server, Wired to Claude

The Model Context Protocol (MCP) is a standard way to expose tools to any MCP-capable client, Claude Desktop, IDEs, or your own agents, so you write an integration once and reuse it everywhere. In this tutorial you build an MCP server in TypeScript that exposes a single typed tool over the stdio transport, test it with the MCP Inspector, then register it with Claude and call it from a real conversation. You will also learn the one rule that trips up everyone on stdio: never write to stdout. By the end you have a reusable server you can extend with your own tools.