Stienhardt Diamond MCP

What Stienhardt Diamond MCP does

Stienhardt Diamond MCP MCP server gives MCP-compatible assistants structured reference material for diamond and gemology questions. Its education data comes from a dated facts file and a 90-entry encyclopedia, with sources attached to factual and numeric claims. The subject areas include diamond shapes and cuts, the 4Cs, grading, optics, materials, Lab Grown Diamonds, settings, care, buying, and gemology history.

The server also supports practical shopping research. It can estimate face-up dimensions for round, oval, emerald, and Dutch Marquise diamonds; provide current tracked Lab Grown Diamond price context; compare two to five supplied specifications; and search or retrieve products from the hosted Stienhardt catalog.

How it works

The hosted service is available at https://diamond-mcp.stienhardt.workers.dev/mcp as a Streamable HTTP MCP endpoint. It requires no account or API key and exposes 11 tools: eight education tools, compare_diamonds, search_inventory, and get_product. The inventory tools are read-only and query the public Shopify catalog.

Local variants use data packaged in the repository. The Python implementation uses only the standard library, reads facts.json and encyclopedia.json, and makes no network calls. The Node source includes the comparison tool, while the published 0.2.6 packages and Python server retain the original eight-tool education set. A downloadable 0.2.6 MCP Bundle runs locally with Node.js.

Setup and configuration

For a remote connection, configure an MCP client with the hosted endpoint. For local use, download the diamond-mcp-0.2.6.mcpb bundle in an application that supports MCP Bundles, or use the repository's local implementation. The bundle does not require an account, API key, Python environment, or package-manager command.

No environment variables are documented as required. The hosted endpoint is the option to choose when live inventory access is needed; local builds intentionally do not make network requests.

Tools and capabilities

• verify_diamond_report returns the official verification location and a three-step checklist for GIA, IGI, or GCAL reports. It does not inspect or verify a stone.
• faceup_size estimates millimeter dimensions by scaling vetted one-carat anchors with the cube root of carat weight.
• define and search_encyclopedia retrieve full entries or ranked definition snippets, including aliases and related terms.
• lab_grown_grading_landscape and lab_grown_price_index return sourced, dated market and grading information.
• compare_diamonds reports supplied measurements, length-to-width ratios, price per carat, differences from the first stone, and missing data. It does not select a winner or appraise.
• search_inventory and get_product return public catalog details, prices, links, options, images, and availability fields.

Limitations and notes

Stienhardt Diamond MCP MCP server is an education and shopping-reference tool, not an appraisal or grading service. Users should verify an actual grading report on the issuing laboratory's website. Face-up measurements are approximate because proportions vary between stones. Price-index results are dated market context rather than investment advice.

Hosted product links and selected education responses can include Stienhardt attribution parameters. Loose-diamond catalog results are flagged with availability_verified: false, so assistants should not present them as independently confirmed availability. The local server cannot provide hosted inventory results because it makes no network calls.