Harness Atlas — MCP server

A remote Model Context Protocol server for sourcing wire harnesses and cable assemblies. It answers two questions an agent cannot answer from general web knowledge: who manufactures this, and what part can replace this one.

Hosted, public, no API key, nothing to install.

https://harnessatlas.com/api/mcp

Listed in the official MCP registry as io.github.pawel-kowalczyk/harness-atlas.

The endpoint moved to harnessatlas.com on 2026-08-24 (manifest v0.2.0). The previous Supabase URL still works and is not being retired, so existing clients keep functioning — but this is the address to use.

Why it exists

Wire-harness sourcing data is scattered across trade directories, PDF catalogues and manufacturer sites that general-purpose models summarise badly and cite unreliably. Harness Atlas is a structured directory of the sector with per-field provenance, exposed over MCP so an agent can query it directly instead of guessing.

Tools

find_manufacturer

Search the directory of wire-harness and cable-assembly manufacturers. All parameters optional.

Returns name, HQ country and city, website, industries served, plant count, capabilities and a profile URL.

find_alternative

Cross-reference a component part number — connectors, terminals, seals, cable protection — against the XrefBase equivalence graph. part_number is required; manufacturer is optional and disambiguates an MPN that exists under several makers (aliases such as TE and H+S are accepted). Punctuation and case are normalised, so 1-967616-1 and 19676161 both match.

Results are grouped by relationship strength, and the groups are not interchangeable:

Every claim carries a confidence level and, where one exists, a public source URL. The grouping is the point: a tool that returns one flat list of "alternatives" invites an agent to propose a mating connector as a replacement part.

Connecting

Claude Code

claude mcp add --transport http harness-atlas https://harnessatlas.com/api/mcp

Claude Desktop / any client taking a remote MCP URL — add to your MCP config:

{
  "mcpServers": {
    "harness-atlas": {
      "type": "streamable-http",
      "url": "https://harnessatlas.com/api/mcp"
    }
  }
}

Straight JSON-RPC, to try it without a client:

curl -s -X POST https://harnessatlas.com/api/mcp \
  -H 'Content-Type: application/json' \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{
        "name":"find_manufacturer",
        "arguments":{"country":"Poland","industry":"automotive","limit":3}}}'

The data, honestly

• 513 published manufacturers, 715 plants, 65 countries. Coverage is deepest in Europe, with meaningful presence in North America and Asia.
• Profiles are compiled from public sources and manufacturer self-declaration. Independent verification is in progress and is not yet reflected in most listings — treat capability and certification claims as sourced, not audited, and follow the profile URL to the operator's own material before relying on one commercially.
• Equivalence claims carry their own confidence level and a source URL where a public one exists. verified_replacements is the only group that should be read as a substitution recommendation, and even that warrants engineering review for a safety-relevant application.
• Corrections are welcome — open an issue here or use the contact form on the site.

Scope

Harness Atlas is a directory and reference service. It does not broker, quote or transact, and listing is not endorsement.

This repository

The server runs as a hosted endpoint; its implementation is not open source. This repository is the public home for the server: its registry manifest, documentation and examples.

server.json is a mirror published for registry discovery. The canonical copy lives with the implementation and is what mcp-publisher publishes — if the two ever disagree, the version in the official registry is authoritative.

Links

• Site — https://harnessatlas.com
• About the MCP server — https://harnessatlas.com/mcp
• Official MCP registry entry — io.github.pawel-kowalczyk/harness-atlas

Licence

MIT — covering this repository's contents: the server manifest, documentation and examples.

The licence does not extend to the Harness Atlas directory data returned by the hosted endpoint. That data remains proprietary and is offered for use through the endpoint itself.