Medprice MCP Server

medprice

medprice is a small local bridge to FineRx's hosted MCP server, a prescription-price service for the US: it knows what a medicine costs with a free discount card at the major pharmacy chains, which stores sit near a ZIP code, and what a medicine sold under a foreign brand name is called in the US.

The bridge keeps no drug or price data of its own. It serves the upstream server's tool list locally, exactly as captured from the live endpoint, and forwards each tool call upstream, returning the result untouched.

Labelled subset: 18 of 19 tools

The live capture held 19 tools. This rebuild serves 18 of them. One tool is deliberately omitted:

• email_savings_card — omitted. It sends email to an arbitrary address supplied by the caller, an external-sending action outside this server's price-read core, so it is excluded under the program's safety rule. It is not registered, not forwarded, and the test suite asserts its absence from both the local registry and the served MCP tools/list.

One nearby tool is kept on purpose:

• get_savings_card — kept. It returns the FineRx program's own free discount card: the shared program codes printed on every card the service distributes publicly, with usage steps. That is published program data, not a user's payment-card data, and it creates no payment instrument — a read like the price reads around it.

Tools

• compare_prices — one medicine's card price at US pharmacy chains, near a place. Optional: drug, strength, form, quantity, zip, ndc, locale, channel, compare_to.
• ui_prices — the same price answer for a package and place picked inside the FineRx card. Required: slug.
• find_nearby_pharmacies — pharmacy stores within 30 miles, per chain, with the card price when a drug is given. All arguments optional.
• ui_nearby — nearby pharmacies for the package on screen, called by the card itself. All optional.
• get_transfer_steps — how to move a prescription to another chain. All arguments optional.
• compare_basket — card prices for several medicines at once, and which chain was seen pricing the whole list. Required: drugs.
• ui_basket — the same basket for another place, called by the card itself. Required: slugs.
• open_price_finder — open the FineRx search inside the card. Optional: query, locale.
• ui_suggest — medicines matching what is being typed in the FineRx search. Required: q.
• get_savings_card — the free FineRx discount card: its codes, how to use it, how to keep it. See the subset note above. All arguments optional.
• search_drugs — find a medicine by name (brand, generic, misspelled or in another script) and get its slug. Required: query.
• get_drug — strengths, forms and pack sizes of one medicine that have a card price. Required: slug.
• get_dataset_info — what FineRx covers: chains, freshness, store counts, terms. No arguments.
• get_prescription_options — routes to filling a prescription, including having none yet. All optional.
• find_us_equivalent — what a medicine from another country is in the US, and its card price here. Required: brand.
• find_us_equivalents — the same for several foreign medicines at once. Required: brands.
• ui_equivalent — one foreign brand picked in the FineRx search, called by the card itself. Required: brand_slug.
• foreign_brands_for_drug — what a US drug is called abroad. Required: slug.

Configuration

• FINERX_MCP_URL (optional) — override the upstream endpoint. Defaults to https://www.finerxfinder.com/mcp. (The override hook is this rebuild's own labelled reconstruction.)
• FINERX_API_KEY (optional) — when set, every upstream request carries an Authorization: Bearer <key> header. When it is not set, no auth header is sent. (This forwarding is also a labelled reconstruction; the original surface was captured keyless.)

Forwarding mechanics

On the first tool call the client opens a streamable HTTP session with the upstream: a JSON-RPC initialize request (protocolVersion 2025-03-26, clientInfo name medprice), then a notifications/initialized notification, then the tools/call request carrying the caller's arguments unchanged. When the upstream answers initialize with an Mcp-Session-Id header, that value rides on every later request of the session, which is reused for the life of the process. Replies may arrive as plain JSON or as server-sent events; both are read.

Successful upstream results pass through verbatim, including any isError flag the upstream sets. Failures — a JSON-RPC error, a non-2xx status, an unreadable response, or a request that cannot be completed — come back as an isError result whose text starts with medprice error: (this rendering is this rebuild's own labelled reconstruction).

CLI

Each tool is also a subcommand taking one JSON argument string (omit it for tools that take none):

npx @reneturcios/medprice search_drugs '{"query":"lisinopril"}'
npx @reneturcios/medprice compare_prices '{"drug":"lisinopril","zip":"94110"}'
npx @reneturcios/medprice compare_basket '{"drugs":["lisinopril","metformin"]}'
npx @reneturcios/medprice find_us_equivalent '{"brand":"No-Spa"}'
npx @reneturcios/medprice get_dataset_info
npx @reneturcios/medprice --version

Exit codes: 0 on success, 1 on an isError result, 2 on a usage error.

MCP server

npx -y @reneturcios/medprice mcp

MCP client config:

{
  "mcpServers": {
    "medprice": {
      "command": "npx",
      "args": ["-y", "@reneturcios/medprice", "mcp"]
    }
  }
}

Docker

docker run -i ghcr.io/cloudcorprecords/medprice
docker run --rm ghcr.io/cloudcorprecords/medprice --version

The container's default command is mcp, so the first form is a stdio MCP server; any other arguments reach the CLI normally.

Development

npm install
npm run build
npm test
npm run dev

The test suite runs entirely against a stubbed JSON-RPC upstream — no live network calls.

License

MIT — see LICENSE.