[BUG] Using the Java LSP server fails because option "startupTimeout" is not supported

Status Fixed / completed
Reported on v2.1.1
Maintainer reply ✓ Yes — ashwin-ant
Activity 5 comments · opened Jan 8, 2026 · closed Apr 18, 2026
💡 Likely answer: A maintainer (ashwin-ant, collaborator) responded on this thread — see the highlighted reply below.

Preflight Checklist

  • [x] I have searched existing issues and this hasn't been reported yet
  • [x] This is a single bug report (please file separate reports for different bugs)
  • [x] I am using the latest version of Claude Code

What's Wrong?

On startup the Java LSP server fails to load. It fails because the ~/.claude/plugins/marketplaces/claude-plugins-official/.claude-plugin/marketplace.json defines an option named startupTimeout which does not appear to be supported for Java. Removing this option causes the server to load and it is available.

What Should Happen?

The java LSP server should load and be available.

Error Messages/Logs

Error: Error: Failed to initialize LSP server plugin:jdtls-lsp:jdtls: LSP server 'plugin:jdtls-lsp:jdtls': startupTimeout is not yet implemented. Remove this field from the configuration.

Steps to Reproduce

  1. Install the Java LSP plugin jdtls-lsp
  2. Make sure that it's enabled
  3. Start a new session with claude --debug
  4. Look at the debug log for the above error
  5. Edit ~/.claude/plugins/marketplaces/claude-plugins-official/.claude-plugin/marketplace.json and remove the startupTimeout option from the jdtls-lsp plugin settings.
  6. Start a new session with claude --debug
  7. Look in log and verify error does not appear.
  8. For Claude to use the LSP tool to verify it is working correctly.

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.1

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Warp

Additional Information

_No response_

View original on GitHub ↗

5 Comments

jmalpasuto · 7 months ago

Same issue with the Kotlin LSP

mrclrchtr · 7 months ago

Can confirm the issue

Omoeba · 6 months ago

The issue is still occurring

ashwin-ant collaborator · 4 months ago

This was fixed in v2.1.50 — The LSP startupTimeout option is now implemented instead of throwing 'not yet implemented'. If you're still seeing this in the latest version, please comment with your version and repro and we'll reopen.

github-actions[bot] · 4 months ago

This issue has been automatically locked since it was closed and has not had any activity for 7 days. If you're experiencing a similar issue, please file a new issue and reference this one if it's relevant.