LangChain4j 1.0.0-alpha1 & Model Context Protocol client implementation and sample

[jmartisk]

Fixes #1146

[geoand]

Very cool @jmartisk!

Can you provide a list of things that need to be done in order for this to move out of draft?

[jmartisk]

Yea I think it's basically ready except we need a langchain4j release that integrates this. If the langchain4j side gets any changes before the release, we might obviously need to adjust here.

[geoand]

Cool thanks.

@langchain4j do you a timeline in your head about when the next LangChain4j release will go out?

[langchain4j]

@geoand targeting for tomorrow, but most probably this Friday

[geoand]

Awesome, thanks!

[geoand]

We'll probably also need @cescoffier's writing talents on this one :)

[jmartisk]

I'm planning to write up a blog post too :)

[jmartisk]

Seems we have a server-side framework ready (https://github.com/quarkiverse/quarkus-mcp-server/releases/tag/1.0.0.Alpha1), I'll probably try to add some tests that run our client against our server (rather than a dumb mock server). That could go into a new module inside integration-tests here, WDYT @mkouba and @geoand ?

[geoand]

Makes perfect sense to me!

[mkouba]

Seems we have a server-side framework ready (https://github.com/quarkiverse/quarkus-mcp-server/releases/tag/1.0.0.Alpha1), I'll probably try to add some tests that run our client against our server (rather than a dumb mock server). That could go into a new module inside integration-tests here, WDYT @mkouba and @geoand ?

Makes sense! Keep in mind that it's still very alpha ;-).

[geoand]

Keep in mind that it's still very alpha ;-)

As if we needed convincing of whether to ship it 😂

[jmartisk]

Ok this will need some adjustments after langchain4j/langchain4j#2315

[jmartisk]

I've pushed an upgrade to LangChain4j 1.0.0-alpha1 as part of this. Haven't had time for the integration test yet, that may have to wait until after Christmas.

[jmartisk]

Tests are passing now, except some Ollama stuff that fails with 404s, not sure what that is, it doesn't look related to the change?!

[geoand]

But those tests pass in main, right?

[jmartisk]

Ah, a Wiremock declaration needed a slight change, hopefully, I've fixed it now...

[geoand]

Awesome stuff!

[quarkus-bot]

Status for workflow Build (on pull request)

This is the status report for running Build (on pull request) on commit f7d76a0.

✅ The latest workflow run for the pull request has completed successfully.

It should be safe to merge provided you have a look at the other checks in the summary.

[geoand]

I can't release because I am getting:

[WARNING] The POM for io.quarkiverse.langchain4j:quarkus-langchain4j-mcp-deployment:jar:999-SNAPSHOT is missing, no dependency information available
[ERROR] Quarkus Extension Dependency Verification Error
[ERROR] Deployment artifact io.quarkiverse.langchain4j:quarkus-langchain4j-mcp-deployment::jar:999-SNAPSHOT was found to be missing dependencies on the Quarkus extension artifacts marked with '-' below:
[ERROR] -     io.quarkiverse.langchain4j:quarkus-langchain4j-mcp::jar
[ERROR] -     io.quarkus:quarkus-arc-deployment::jar
[ERROR] -         io.quarkus:quarkus-core-deployment::jar
[ERROR] -     io.quarkus:quarkus-rest-client-jackson-deployment::jar
[ERROR] -         io.quarkus:quarkus-rest-jackson-common-deployment::jar
[ERROR] -             io.quarkus:quarkus-rest-common-deployment::jar
[ERROR] -             io.quarkus:quarkus-jsonp-deployment::jar
[ERROR] -         io.quarkus:quarkus-rest-client-deployment::jar
[ERROR] -             io.quarkus:quarkus-rest-client-jaxrs-deployment::jar
[ERROR] -             io.quarkus:quarkus-smallrye-stork-deployment::jar
[ERROR] -             io.quarkus:quarkus-rest-client-config-deployment::jar
[ERROR] -             io.quarkus:quarkus-tls-registry-deployment::jar
[ERROR] -     io.quarkiverse.langchain4j:quarkus-langchain4j-core-deployment::jar
[ERROR] -         io.quarkus:quarkus-jackson-deployment::jar
[ERROR] -         io.quarkus:quarkus-qute-deployment::jar
[ERROR] -         io.quarkus:quarkus-vertx-deployment::jar
[ERROR] -             io.quarkus:quarkus-netty-deployment::jar
[ERROR] -             io.quarkus:quarkus-mutiny-deployment::jar
[ERROR] -                 io.quarkus:quarkus-smallrye-context-propagation-deployment::jar
[ERROR] -             io.quarkus:quarkus-virtual-threads-deployment::jar

Nothing in the extension looks out of the ordinary...

[jmartisk]

From the log, it seems the mcp/deployment module was not in the build reactor at all, for some reason.

[geoand]

Yeah, I'm trying to compare with other modules to see if there are any useful hints

[jmartisk]

I tend to think that #1181 will fix it

[geoand]

#1182

[geoand]

Ah, you beat me to it :)