About meddata
meddata wraps the MedData API as tools for MCP clients to look up drug and supplement information and check interactions. It distinguishes source-backed negative results from combinations that are not covered, and can return assessment details.
Key features
- 01Search drugs by brand or generic name
- 02Look up drug profiles by RxCUI or NDC
- 03Search supplements and retrieve fact sheets
- 04Check drug and supplement interactions
- 05Assess routines with supporting references
- 06View usage and plan limits
Use cases
- 01Retrieve a drug’s full profile
- 02Check a drug and supplement combination
- 03Review sources used in a routine assessment
- 04Check current billing-period usage
MCP support
Exposes MedData API lookups for drugs, supplements, and interactions to MCP clients as tools. Supports stdio and streamable-HTTP transports.
Configuration
Local server config is the same for every client. Copy it into your client’s MCP config file.
uvx meddata-mcpMEDDATA_API_KEYSecretMedData API key. Get a free one (250 calls/month, no card) at https://meddata.anthesia.ioLocal servers need a runtime on your machine (e.g. Node.js 18+). Config file locations differ by client; see your client’s docs.
Tools
Local servers expose tools only once running on your machine, and the maintainer has not provided a tool list.
Details
From the project READMEMedData MCP Server
mcp-name: io.github.anthesiallc/meddata
A Model Context Protocol server that exposes the MedData API as tools, so any MCP client (Claude Desktop, Cursor, ChatGPT connectors, or an agent framework) can look up drug and supplement data and check interactions conversationally.
It's a thin wrapper: each tool maps to one MedData REST endpoint. All the data work happens in the API.
Tools
| Tool | What it does |
|---|---|
search_drugs | Search drugs by brand or generic name; returns RxCUI + details |
get_drug | Full drug profile by RxCUI |
get_drug_by_ndc | Drug profile by NDC package code |
search_supplements | Search supplements by name; returns supplement IDs |
get_supplement | Full supplement fact sheet by ID |
check_interactions | Interactions across a mixed list of 2-10 drugs/supplements |
assess_routine | Full assessment of a routine: per-pair coverage, sources, timing and food conditions |
get_usage | Current billing period usage and plan limit |
check_interactions vs assess_routine
check_interactions returns a flat list of interactions. assess_routine
returns the reasoning: what each submitted name resolved to, what was consulted
for every pair, and the document behind each finding. Reach for it when the
answer will be explained or acted on rather than just displayed.
The distinction that matters most is in pairs_checked[].status:
| status | means |
|---|---|
finding | one or more grounded findings, listed in findings[] |
no_finding_in_sources | a source covering this kind of pair was consulted and had nothing. Absence of a finding is not evidence of safety |
not_covered | no source covers this kind of pair, so it was not assessed. Most supplement-supplement pairs land here |
unresolved | an item did not resolve, so nothing could be checked |
not_covered and no_finding_in_sources are different answers, and a flat
empty list cannot tell them apart.
assess_routine also takes class_matching (default off). With it on, a drug
matches the therapeutic classes a supplement record names, not only the drug
names it lists; those findings carry basis.level: "class" and name the class,
so an inferred match stays distinguishable from an explicit one. Findings also carry basis.level
(formulation / ingredient / class) saying how closely the source matches
what was submitted, three-state timing and food conditions where silence is
not_documented rather than "no effect", and references[] with the document
version and the verbatim passage.
Get an API key
Free tier is 250 calls/month, no credit card:
curl -X POST https://meddata.anthesia.io/api/v1/signup \
-H 'Content-Type: application/json' \
-d '{"email":"[email protected]"}'
The key comes back in the api_key field of the response.
Install and run
The easiest way is with uv (no manual venv needed):
# stdio transport (default — for Claude Desktop, Cursor, most local clients)
MEDDATA_API_KEY=md_your_key uvx meddata-mcp
# streamable-HTTP transport (for remote / web clients)
MEDDATA_API_KEY=md_your_key uvx meddata-mcp --http
Or install with pip into its own environment:
pip install meddata-mcp
MEDDATA_API_KEY=md_your_key meddata-mcp
Note: install into a dedicated environment. The
mcpSDK requires a newerstarlettethan the MedData API app pins, so the two will conflict if installed together.
Environment variables:
MEDDATA_API_KEY(required) — your MedData API key.MEDDATA_BASE_URL(optional) — defaults tohttps://meddata.anthesia.io.MEDDATA_TIMEOUT(optional) — request timeout in seconds, default30.
Client configuration
Claude Desktop
Add to claude_desktop_config.json (Settings → Developer → Edit Config):
{
"mcpServers": {
"meddata": {
"command": "uvx",
"args": ["meddata-mcp"],
"env": { "MEDDATA_API_KEY": "md_your_key" }
}
}
}
Cursor
Add the same block to ~/.cursor/mcp.json (or the project .cursor/mcp.json).
Smithery (hosted, no install)
The server is hosted on Smithery, so MCP clients that support Smithery can connect without installing anything. You provide your MedData API key in the Smithery config and it routes to the server.
LangChain / LangGraph
Any LangChain or LangGraph agent can use these tools through
langchain-mcp-adapters:
# pip install langchain-mcp-adapters langgraph "langchain[anthropic]"
from langchain_mcp_adapters.client import MultiServerMCPClient
client = MultiServerMCPClient(
{
"meddata": {
"transport": "stdio",
"command": "uvx",
"args": ["meddata-mcp"],
"env": {"MEDDATA_API_KEY": "md_your_key"},
}
}
)
tools = await client.get_tools()
# hand `tools` to a LangGraph/LangChain agent, e.g.
# from langgraph.prebuilt import create_react_agent
# agent = create_react_agent("anthropic:claude-opus-4-8", tools)
LlamaIndex works the same way via its MCP tool spec.
Develop from source
git clone https://github.com/anthesiallc/meddata-mcp && cd meddata-mcp
python -m venv .venv
.venv/Scripts/python -m pip install -e ".[http]" # Windows; [http] adds uvicorn for --http
# .venv/bin/pip install -e ".[http]" # macOS/Linux
MEDDATA_API_KEY=md_your_key .venv/Scripts/python -m meddata_mcp.server
Notes
- Data is for informational purposes only and is not medical advice.
- Interaction data comes from established medical databases; an empty result means none were found in those sources, not that a combination is proven safe.
Comments
New to MCP?
From what the protocol is to installing your first server, these answers cover most first questions.
An open protocol that defines how AI applications connect to external tools and data in a uniform way. Clients talk to the model; MCP servers provide tools, resources and prompt templates. They exchange standard messages, so one server can be reused by many clients.