Steel Brain

An MCP server providing steel domain knowledge to AI agents — grade properties, substitution verdicts, and mill-cert guidance, delivered as MCP tools your agent can call.

Also available as a REST API at https://api.steelbrain.dev.

MCP server

Steel Brain is a Model Context Protocol server. It exposes three MCP tools over stdio transport:

Running the MCP server

pip install -r requirements.txt
python -m steel_brain.mcp_server

Starts the MCP server on stdio transport, ready for any MCP client (Claude Desktop, Claude Code, or any MCP-compatible agent).

Example MCP client config

{
  "mcpServers": {
    "steel-brain": {
      "command": "python",
      "args": ["-m", "steel_brain.mcp_server"]
    }
  }
}

Built with the official MCP SDK (mcp package), registering three tools via the standard MCP tool interface.

Related MCP server: simpson-strong-agent

Why Steel Brain

LLMs guess at steel. They will tell you 4140 annealed can stand in for 4140 pre-hardened, and scrap the job. Steel Brain answers from a human-verified knowledge base built by a working steel trader, and returns an honest "not in knowledge base" rather than a confident guess.

The valuable part is the substitution and cert logic:

• 4140RB to 4140QT (annealed vs pre-hardened): invalid, same alloy, opposite heat-treat

• 316L to 304L for marine: invalid, different corrosion class

• EH36 to S355 structural: valid one way, conditional the other

• Seamless vs ERW for pressure service: never interchangeable

Coverage

23 grades across carbon, alloy, stainless. Round bar, hollow bar, plate, pipe. 39 substitution rules, 4 cert guides.

REST API (alternative to MCP)

Same knowledge over REST at https://api.steelbrain.dev :

curl "https://api.steelbrain.dev/v1/grade/4140QT" -H "X-API-Key: YOUR_KEY"
curl "https://api.steelbrain.dev/v1/substitution?from_grade=316L&to_grade=304L&application=machined" -H "X-API-Key: YOUR_KEY"

Free tier at launch. Contact: dryow.jt@gmail.com

Honesty by design

• Grade properties: published-standard ranges (ASTM/EN/JIS/API/ABS), labelled as such.

• Substitution + cert logic: trade-verified, dated rulings from a working trader.

• Unknown grades: honest "not in knowledge base," never fabricated.

Development

python -m pytest tests/    # 15 tests (10 acceptance + 5 domain-safety guards)

License

Code: MIT (see LICENSE). Knowledge base (kb/): proprietary (see NOTICE).