About Datomic MCP Server
Datomic MCP Server is an MCP server built with the Modex library that lets AI models query Datomic databases. It runs as a Java uberjar and is configured through the DATOMIC_URI environment variable. The project is released under the MIT licence.
Key features
- 01Concurrent query handling
- 02Query support via datomic.api/q and pull
- 03q-with tool for datomic.api/with
- 04Support for datoms, entity and touch APIs
Use cases
- 01Letting an AI model query a Datomic database
- 02Reading entity data through pull and entity lookups
MCP support
This project is an MCP server that exposes Datomic database query tools to MCP clients.
Configuration
Local server config is the same for every client. Copy it into your client’s MCP config file.
We haven’t collected a package or remote endpoint for this server. Follow the instructions in the project README.
Tools
Local servers expose tools only once running on your machine, and the maintainer has not provided a tool list.
Details
From the project READMEDatomic MCP Server
Built with Modex.
Set environment variable DATOMIC_URI in your MCP config. Example below.
Build Uberjar & Configure Claude Desktop
{
"mcpServers": {
"modex-datomic-mcp": {
"command": "java",
"args": ["-jar", "/Users/petrus/code/datomic-mcp/target/theronic-datomic-mcp-0.3.0.jar"],
"env": {"DATOMIC_URI": "<your datomic URI here>"}
}
},
"globalShortcut": ""
}
Datomic API Support
- Concurrent queries (async message handling since Modex 0.3.0)
-
datomic.api/q -
datomic.api/datoms -
datomic.api/with(viaq-withtool) -
datomic.api/pull -
datomic.api/pull-many -
datomic.api/entity -
datomic.api/touch -
datomic.api/entid -
datomic.api/transact– not sure if good idea :) - Send Progress Messages Connection Progress
- Better cursor-based pagination
- Stable
dbbasis (currently each query runs(d/db conn)) – easy to fix. -
d/as-ofsupport. Related to basis above.
License
MIT Licence. Free for commercial & non-commercial use.
All I ask is that if you find a bug in datomic-mcp or Modex, please report it :)
Note that Modex itself has a different licence.
Author(s)
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.