Model Context Protocol (MCP)

[amotl]

About

Model Context Protocol (MCP)

Details

Hereby adding references to mcp-mongo-server and PostgreSQL.

It could be super simple to just remove the BEGIN TRANSACTION and ROLLBACK in postgres/index.ts and we would be done?

Very simple indeed, see mcp_tinybird/tb.py.

Get started with Claude Desktop and Neon MCP Server provides a good example how an MCP integration with Claude can be presented. Any volunteers to evaluate the outcome shared above together with Claude, so we could ramp up a similar page?

Thoughts

MCP looks reasonable, possibly powerful, but on the other hand conceptually also a bit weak.

References

• Research notes

/cc @kneth, @surister, @hlcianfagna

[amotl]

There is a range of out-of-the-box options to evaluate for connectivity.

• PostgreSQL - Read-only database access with schema inspection, see @modelcontextprotocol/server-postgres.
• DBHub - Universal database MCP server connecting to MySQL, PostgreSQL, SQLite, DuckDB and etc.
• JDBC - Connect to any JDBC-compatible database and query, insert, update, delete, and more. Supports MySQL, PostgreSQL, Oracle, SQL Server, sqllite and more.

[amotl]

Hi again. Let us share a little update here.

• @surister shared a few excellent hands-on updates including screenshots,

  

  [...] and published the MCP server cratedb-mcp based on his explorations. Thanks a stack!

• Also drilling from the other side, we added a few example programs that explore other MCP server implementations that could be relevant in this context, wrapping it up into a little summary, where you can optimally explore what's inside corresponding projects, based on their API capabilities, exposed as Markdown/YAML.

• @kneth will host a meeting next week for people who want to join the procedures. Thanks!

[amotl]

Quarkus MCP server for JDBC

JDBC doesn't sound too bad. I am trying to follow the README.

docker run --rm -it --name=cratedb \
  --publish=4200:4200 --publish=5432:5432 \
  --env=CRATE_HEAP_SIZE=2g crate/crate:nightly \
  -Cdiscovery.type=single-node

brew install jbang
jbang run --java=21 jdbc@quarkiverse/quarkus-mcp-servers jdbc:postgresql://localhost:5432/doc -u crate

NB: When using jbang, make sure it does not interfere with any jenv installation. When in doubt, deactivate it.

[amotl]

Evolution of the MCP specification

The spec for MCP transport has changed from SSE to Streamable HTTP.

• Transition Server Side Events to Streamable HTTP stuzero/pg-mcp-server#13
• Streamable HTTP Support modelcontextprotocol/python-sdk#405

/cc @surister, @kneth

[amotl]

Update 2025W15: MCP interoperability

Other vendors also start using MCP. Let's check the interoperability landscape a bit.

[amotl]

... with LangChain

I had been waiting / not actively looking for how the LangChain ecosystem will handle MCP, in which spirit I just discovered the Quick Primer on MCP Using Ollama and LangChain via HN.

It looks like the langchain-mcp-adapters package provides the corresponding bridge/gateway/compatibility layer here.

Relevant feature: Convert MCP tools into LangChain tools that can be used with LangGraph agents.

• Ticket: Compatibility with MCP langchain-cratedb#43

[amotl]

... with n8n

• https://n8n.io/integrations/cratedb/and/mcp-client-tool/
• https://docs.n8n.io/integrations/builtin/cluster-nodes/sub-nodes/n8n-nodes-langchain.toolmcp/

[amotl]

MCP goes monitoring

• https://github.com/grafana/mcp-grafana
• https://github.com/pab1it0/prometheus-mcp-server

[amotl]

... with OpenAPI

Thinking about how to bridge the gap between OpenAPI and MCP, and just doing it.

[amotl]

Update 2025W16: MCP security

A few pieces have been written and collected that elaborate about security details of MCP.

• Others started writing about the flaws of MCP the other day.

• Everything Wrong with MCP (discuss) enumerates more items.

• The damn vulnerable MCP server (discuss) dedicates a whole project.

• OAuth's Role in MCP Security (discuss) thinks about potential solutions by applying OAuth?

[amotl]

Spec development:

• Auth: MCP Servers are Resource Servers only. Add Protected Resource Metadata to discover Authorization Server modelcontextprotocol/modelcontextprotocol#338 (HN)

[amotl]

Update 2025W18: Announcements

• Anthropic made an annoncement: Claude can now connect to your world (with MCP). (HN)
• Also, MongoDB has announced their MCP server.
• KlavisAI is an enterprise-grade MCP integration layer. (HN)

-- Thanks, @kneth.

[kneth]

Update 2025W20: MCP servers

• Google's MCP Toolbox for Databases: https://github.com/googleapis/genai-toolbox