[Bug]: dbt-lsp fails to connect and panics

[dataders]

What happened?

TIL that there's already an LSP built in! however, I'm struggling to see it connect.

Below is the error message found in the claude's debug logs as well as a longer snippet if that's helpful. I'm not sure what to do next to debug... please advise! cheers

2026-02-05T03:09:51.632Z [DEBUG] [LSP PROTOCOL plugin:dbt-lsp:dbt] Sending request 'initialize - (0)'.
2026-02-05T03:09:51.640Z [DEBUG] [LSP SERVER plugin:dbt-lsp:dbt] thread 'main' (2248834) panicked at crates/dbt-lsp/src/async_lsp_server.rs:645:10:
Failed to connect to LSP client: Os { code: 61, kind: ConnectionRefused, message: "Connection refused" }
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
2026-02-05T03:09:51.656Z [DEBUG] LSP server plugin:dbt-lsp:dbt connection closed
2026-02-05T03:09:51.656Z [ERROR] Error: Error: LSP server plugin:dbt-lsp:dbt crashed with exit code 101
    at <anonymous> (/$bunfs/root/claude:2167:21472)
    at emit (node:events:98:22)
    at #handleOnExit (node:child_process:520:14)
    at processTicksAndRejections (native:7:39)

Steps to Reproduce

add dbt-mcp to Claude's config. start Claude

Deployment

Remote MCP server

Environment

No response

Relevant log output

2026-02-05T03:09:51.615Z [DEBUG] Loaded 4 installed plugins from /Users/dataders/.claude/plugins/installed_plugins.json
2026-02-05T03:09:51.615Z [DEBUG] Initialized versioned plugins system with 4 plugins
2026-02-05T03:09:51.615Z [DEBUG] MCP server "github": Proxy options: default
2026-02-05T03:09:51.615Z [DEBUG] MCP server "github": HTTP transport options: {"url":"https://api.githubcopilot.com/mcp","headers":{"User-Agent":"claude-code/2.1.31","Authorization":"[REDACTED]"},"hasAuthProvider":true,"timeoutMs":60000}
2026-02-05T03:09:51.616Z [DEBUG] MCP server "github": HTTP transport created successfully
2026-02-05T03:09:51.616Z [DEBUG] MCP server "github": Client created, setting up request handler
2026-02-05T03:09:51.616Z [DEBUG] MCP server "github": Starting connection with timeout of 30000ms
2026-02-05T03:09:51.616Z [DEBUG] MCP server "github": Testing basic HTTP connectivity to https://api.githubcopilot.com/mcp
2026-02-05T03:09:51.616Z [DEBUG] MCP server "github": Parsed URL: host=api.githubcopilot.com, port=default, protocol=https:
2026-02-05T03:09:51.617Z [DEBUG] [API:auth] OAuth token check complete
2026-02-05T03:09:51.618Z [DEBUG] MCP server "github": No token data found
2026-02-05T03:09:51.622Z [DEBUG] Git remote URL: git@github.com:dbt-labs/internal-analytics.git
2026-02-05T03:09:51.622Z [DEBUG] Parsed repository: dbt-labs/internal-analytics from git@github.com:dbt-labs/internal-analytics.git
2026-02-05T03:09:51.622Z [DEBUG] Parsed repository: dbt-labs/internal-analytics from URL: git@github.com:dbt-labs/internal-analytics.git
2026-02-05T03:09:51.622Z [DEBUG] Path /Users/dataders/Developer/internal-analytics already tracked for repo dbt-labs/internal-analytics
2026-02-05T03:09:51.622Z [DEBUG] Loaded 1 LSP server(s) from plugin: rust-analyzer-lsp
2026-02-05T03:09:51.625Z [DEBUG] Loaded 1 LSP server(s) from plugin: dbt-lsp
2026-02-05T03:09:51.626Z [DEBUG] Total LSP servers loaded: 2
2026-02-05T03:09:51.626Z [DEBUG] [LSP SERVER MANAGER] getAllLspServers returned 2 server(s)
2026-02-05T03:09:51.629Z [DEBUG] Queued request handler for plugin:rust-analyzer-lsp:rust-analyzer.workspace/configuration (connection not ready)
2026-02-05T03:09:51.629Z [DEBUG] Starting LSP server instance: plugin:rust-analyzer-lsp:rust-analyzer
2026-02-05T03:09:51.630Z [DEBUG] Queued request handler for plugin:dbt-lsp:dbt.workspace/configuration (connection not ready)
2026-02-05T03:09:51.630Z [DEBUG] Starting LSP server instance: plugin:dbt-lsp:dbt
2026-02-05T03:09:51.630Z [DEBUG] LSP manager initialized with 2 servers
2026-02-05T03:09:51.630Z [DEBUG] LSP server manager initialized successfully
2026-02-05T03:09:51.630Z [DEBUG] Queued notification handler for plugin:rust-analyzer-lsp:rust-analyzer.textDocument/publishDiagnostics (connection not ready)
2026-02-05T03:09:51.630Z [DEBUG] Registered diagnostics handler for plugin:rust-analyzer-lsp:rust-analyzer
2026-02-05T03:09:51.630Z [DEBUG] Queued notification handler for plugin:dbt-lsp:dbt.textDocument/publishDiagnostics (connection not ready)
2026-02-05T03:09:51.630Z [DEBUG] Registered diagnostics handler for plugin:dbt-lsp:dbt
2026-02-05T03:09:51.631Z [DEBUG] LSP notification handlers registered successfully for all 2 server(s)
2026-02-05T03:09:51.631Z [DEBUG] Applied queued notification handler for plugin:rust-analyzer-lsp:rust-analyzer.textDocument/publishDiagnostics
2026-02-05T03:09:51.631Z [DEBUG] Applied queued request handler for plugin:rust-analyzer-lsp:rust-analyzer.workspace/configuration
2026-02-05T03:09:51.631Z [DEBUG] LSP client started for plugin:rust-analyzer-lsp:rust-analyzer
2026-02-05T03:09:51.631Z [DEBUG] Applied queued notification handler for plugin:dbt-lsp:dbt.textDocument/publishDiagnostics
2026-02-05T03:09:51.631Z [DEBUG] Applied queued request handler for plugin:dbt-lsp:dbt.workspace/configuration
2026-02-05T03:09:51.631Z [DEBUG] LSP client started for plugin:dbt-lsp:dbt
2026-02-05T03:09:51.632Z [DEBUG] [LSP PROTOCOL plugin:rust-analyzer-lsp:rust-analyzer] Sending request 'initialize - (0)'.
2026-02-05T03:09:51.632Z [DEBUG] [LSP PROTOCOL plugin:dbt-lsp:dbt] Sending request 'initialize - (0)'.
2026-02-05T03:09:51.640Z [DEBUG] [LSP SERVER plugin:dbt-lsp:dbt] thread 'main' (2248834) panicked at crates/dbt-lsp/src/async_lsp_server.rs:645:10:
Failed to connect to LSP client: Os { code: 61, kind: ConnectionRefused, message: "Connection refused" }
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
2026-02-05T03:09:51.656Z [DEBUG] LSP server plugin:dbt-lsp:dbt connection closed
2026-02-05T03:09:51.656Z [ERROR] Error: Error: LSP server plugin:dbt-lsp:dbt crashed with exit code 101
    at <anonymous> (/$bunfs/root/claude:2167:21472)
    at emit (node:events:98:22)
    at #handleOnExit (node:child_process:520:14)
    at processTicksAndRejections (native:7:39)

[Muizzkolapo]

Based on my understanding this might be more of a Claude Code plugin manager issue than the MCP.

The root cause: transport mismatch/ missing transport config

Claude Code's LSP plugin system uses stdio transport by default:

{
"lspServers": {
  "typescript": {
    "command": "typescript-language-server",
    "args": ["--stdio"]
  }
}
}

But dbt-lsp only supports socket transport (--socket ). Running dbt-lsp --help confirms --socket is the only transport and it's mandatory:

Fix
CC's plugin supports socket transport as well (https://code.claude.com/docs/en/plugins-reference). The plugin just needs to declare it:

  {
    "dbt": {
      "command": "dbt-lsp",
      "transport": "socket",
      "extensionToLanguage": {
        ".sql": "sql"
      }
    }
  }

The default transport is stdio, which is why dbt-lsp crashes it only supports socket. Setting "transport": "socket" tells Claude Code to set up the listening socket before launching the binary.