Mcp

TL;DR Three production MCP servers I run: a docs/wiki wrapper, a personal-finance aggregator, and an inventory-ops tool for a side project. Type hints are your schema. The FastMCP SDK extracts JSON Schema from Python docstrings and type annotations — you almost never hand-write schemas. Flatten nested APIs. If the upstream API returns nested JSON, unwrap it in the MCP tool and return clean markdown or a simple dict — agents prefer predictable structures. Reads always-on, writes gated. Use environment variables (MCP_WRITE=1) or similar to gate mutation tools; put mutations behind a validated service layer and audit every call. Log to stderr, not stdout. Stdio protocol uses stdout for JSON-RPC; anything else breaks the connection. The lineup I’ve written three MCP servers from scratch over the last few months. This is the cookbook — concrete patterns, not theory. If you haven’t read the intro to writing MCP servers, start there; I won’t re-explain the anatomy. ...

TL;DR I ran an audit over my repos going back to March: pull the first commit that introduced each agentic pattern, then go find out when that pattern actually became common practice in the wider ecosystem. The results were humbling in a useful way. Four things I quietly considered myself early on were catch-up, in one case by two years. Four other things turned out to be genuinely ahead of documented practice. The interesting part is what those four have in common, and it is not what I expected. ...

TL;DR Cover art was the gateway drug. The same local ComfyUI install that generates this blog’s headers also strips the cluttered background off a photo of hardware on my bench, upscales a small generation to retina resolution, and batch-produces a consistent set of illustrations from a prompt template. Two Mac Studios mean I can fire a batch at one box and keep working on the other. It’s all driven from scripts and agents, and it all costs $0 per image because it never leaves the house. ...

TL;DR I don’t pay for stock photos and I don’t open Canva. Every raster image on this blog is generated on a Mac Studio sitting three feet from me, by asking Claude Code to call a generate_image MCP tool that wraps ComfyUI. The pipeline is: prompt → ComfyUI (MPS) → PNG on disk → upload_media.py → S3 → CloudFront → a Markdown reference in the post. It costs $0 per image, takes ~15 seconds, and the whole thing is repeatable because the prompt and settings live in the commit history. ...

TL;DR Model Context Protocol (MCP) is a transport layer that lets Claude and other LLM agents call local tools with typed signatures and structured responses. Any HTTP API running on your homelab — ComfyUI, a wiki, a dashboard, a custom service — can become a set of agent-callable tools by wrapping it in a FastMCP server. A typical server takes 150–250 lines of Python, exposes 3–5 tools via @mcp.tool() decorators, and runs as a stdio process. The pattern scales from single-purpose (image generation) to multi-tool (queue status, model listing, system stats) without complexity explosion. This post shows the anatomy by dissecting the ComfyUI MCP server: how to build workflows, poll for completion, parse results, and return structured JSON that agents actually use. ...

TL;DR I deployed ComfyUI natively on my Mac Studio M3 Ultra using Apple’s MPS GPU backend, proxied it through k3s Traefik ingress with Authentik SSO, wired it into Open WebUI as the image generation backend (replacing $0.04/image Bedrock calls), and built an MCP server so AI agents can generate images programmatically. The whole pipeline is Ansible-managed and generates images for free on local hardware. Why native instead of containerized ComfyUI needs GPU access. On Linux, that’s straightforward — pass through the GPU via device plugins. On macOS, there’s no container runtime that exposes MPS (Metal Performance Shaders) to containers. Docker Desktop on Mac runs a Linux VM — no Metal, no MPS. ...