Hardware Spec Assembly vs build123d MCP
Hardware Spec Assembly is no longer listed on any marketplace we read: these are its last known data, as of 2026‑11‑07.
Hardware Spec Assembly is a plugin bundle for AI coding tools published by danielrosehill. No marketplace we read lists it any more. build123d MCP is an MCP server published by pzfreo. Marketplaces we read that list it: 2 (Official MCP Registry, PyPI (MCP servers)). As of our marketplace pass on 2026-11-13. A plugin in this pair is no longer listed on any marketplace we read, so search engines are asked not to index the page.
Where each is published
| Marketplace |  build123d MCP | |
|---|---|---|
| Community marketplace danielrosehill/claude-code-plugins | Removed on 2026-11-07 Version: 1.1.0 Forks (GitHub): 0 Stars (GitHub): 0 Not marked · First seen |
Not listed |
| Official MCP Registry | Not listed | Listed Version: 0.3.91 Downloads/month (PyPI): 5 102 Downloads/week (PyPI): 1 237 Forks (GitHub): 20 Stars (GitHub): 149 Not marked · First seen |
| PyPI (MCP servers) | Not listed | Listed Version: 0.3.91 Downloads/month (PyPI): 5 102 Downloads/week (PyPI): 1 237 Forks (GitHub): 20 Stars (GitHub): 149 Not marked · First seen |
Each figure is the marketplace's own and is never added up across marketplaces. A marketplace that publishes no figure shows none: no number is not zero.
The facts side by side
| Fact | Hardware Spec Assemblyno longer listed · | build123d MCP |
|---|---|---|
| Marketplaces that list it (differs) | 0 | 2 |
| Stars (GitHub) (differs) | 0 | 149 |
| Forks (GitHub) (differs) | 0 | 20 |
| Last release (differs) | Not published | 2026-10-16 |
| Where it runs (differs) | Installs as a plugin bundle | On your machine (build123d-mcp) |
| Transport (differs) | Not stated | stdio |
| Tools it declares | Not published | Not published |
| Environment variables it asks for | Not published | Not published |
| Parts of the bundle (differs) | 16 | Not a bundle |
| Licence (differs) | MIT | Not stated |
| Repository (differs) | github.com/danielrosehill/claude-hardware-spec-assembly-plugin | github.com/pzfreo/build123d-mcp |
| Changes in the last 7 days (differs) | 2 | 0 |
| First seen (differs) | 2026-10-15 | 2026-10-11 |
Lines where the two differ have a tinted background and bold values. No value is marked better or worse: a plugin no marketplace lists any more is shown with its last known data, which we do not rank against current figures.
What to use instead of Hardware Spec Assembly
Plugins still listed whose own names, descriptions, tools and skills are closest in meaning to it. Comparable, not endorsed.
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Source-linked robotics projects, bills of materials and components for AI agents.
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catalog ai.partsgraph/catalog
Search real parts with datasheet-provenance specs, check compatibility and compose priced BOMs.
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KiCad electronics design skills. Analyze schematics, review PCB layouts, download datasheets, source components, and prep boards for fabrication.
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easyeda-mcp-pro io.github.oaslananka/easyeda-mcp-pro
MCP server for EasyEDA Pro: PCB inspection, BOM, exports, and hardware review.
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Network hardware BOMs, built inside your AI assistant
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Electronic component datasheets for AI agents: pinouts, specs, package info and design checks.
What each says it does
Hardware Spec Assembly
Define hardware project BOMs with ESP32-first focus — onboarding captures location/vendors/on-hand gear, then skills for spec creation, live web research of parts (AliExpress/Adafruit/etc.), budgeting, sourcing, compatibility checks, wiring specs, PCB design starting points, assembly instructions, 3D-printable suggestions, and AI-generated mockups via fal.ai nano-banana.
build123d MCP
AI-driven 3D CAD via build123d: execute, render, measure, and export geometry interactively.
How to run each
Hardware Spec Assembly
No data for an automatic command: what its marketplaces declare does not say unambiguously how to connect it.
build123d MCP As a local MCP server: PyPI package
claude mcp add --transport stdio build123d-mcp -- uvx build123d-mcpCommands built only from what the marketplaces declare; the full set for every client is on each card.
Tools each declares
Neither one's marketplaces publish a list of tools, so there is nothing to compare.
Settings each asks for
Neither one's marketplaces publish the settings it asks for.
What it can do: Hardware Spec Assembly · What it can do: build123d MCP · Compare two other plugins
Data comes from public marketplace files in GitHub repositories of their authors. Data comes from the Official MCP Registry (registry.modelcontextprotocol.io), CC0 1.0. Package data comes from the Python Package Index (pypi.org). Figures come from our own regular passes over the marketplaces, last read on . We publish no contact details for plugin publishers.