Nist Fluid Properties MCP server

@pipeworx/nist-fluid-properties

Density, viscosity, thermal conductivity, speed of sound, enthalpy, entropy, Cv/Cp and phase for ~76 reference fluids — water, nitrogen, oxygen, argon, carbon dioxide, light hydrocarbons, and common refrigerants (R11-RC318) — at a caller-given temperature and pressure, or along the liquid/vapor saturation curve. Every value carries its unit.

Part of Pipeworx — an MCP gateway connecting AI agents to 1851+ live data sources. This is an independent, unofficial integration — not affiliated with, endorsed by, or published by the upstream provider.

Tools

— density, specific volume, internal energy, enthalpy, entropy, Cv, Cp, speed of sound, Joule-Thomson coefficient, viscosity, thermal conductivity and phase (liquid/vapor/supercritical) at one temperature/pressure point.

• nistfluidproperties(fluid, temperature, temperatureunit?, pressure, pressureunit?)

— give a saturation temperature (returns the matching saturation pressure) or a saturation pressure (returns the matching saturation temperature), plus liquid- and vapor-side density, enthalpy, entropy, viscosity, thermal conductivity and surface tension on the phase boundary.

• nistfluidsaturation(fluid, temperature? OR pressure?, temperatureunit?, pressureunit?)

filtered by a substring of the name or refrigerant code. An unrecognized fluid argument to either of the tools above also returns this same list.

• nistfluidlist(query?) — the ~76 fluids this pack covers, optionally

Auth

Keyless.

Data sources

Systems. A public, keyless web form; every call proxies it live. The only thing this pack bakes in is a ~76-row fluid-name-to-NIST-id lookup table (not the measurements) so a caller can say "water" or "R134a" instead of NIST's internal identifier.

• NIST, Chemistry WebBook SRD 69 — Thermophysical Properties of Fluid

Notes

property form does not carry a pseudo-pure "air" entry — query nitrogen, oxygen and argon separately if that's what you need.

• "Air" is not in this dataset as a single fluid. NIST's own fluid-

loosely (case/space/hyphen-insensitive): "water", "H2O", "co2", "Carbon Dioxide", "R134a", "r-134a" all resolve.

• Fluid names, formulas and refrigerant codes are all accepted and matched

point, past its upper temperature/pressure limit, or an otherwise unstable point) comes back from NIST as a range error — surfaced as a user_error: with a suggestion to try a condition nearer standard temperature/pressure.

• Requesting a condition outside a fluid's valid range (below its triple

(1 cP = 1 mPa·s) — no conversion needed if your use case wants SI.

• Viscosity is returned in cP, which is numerically identical to mPa·s

Quick Start

Add to your MCP client (Claude Desktop, Cursor, Windsurf, etc.):

{
  "mcpServers": {
    "nist-fluid-properties": {
      "url": "https://gateway.pipeworx.io/nist-fluid-properties/mcp"
    }
  }
}

What this endpoint actually serves

tools/list at https://gateway.pipeworx.io/nist-fluid-properties/mcp returns the tools in the table above plus the shared Pipeworx meta-tools — askpipeworx, discovertools, search_within, remember/recall and the rest of the gateway-wide set. So the tool count you see is larger than this table: a single-pack endpoint currently lists roughly 30 shared tools alongside the pack's own. The connection's initialize response states its exact scope, and is the authoritative answer for a given day.

Shortened. The full README is on GitHub.