Skip to content

[BUG] MCP tool not available to model despite successful registration #27159

@dmb0058

Description

@dmb0058

Preflight Checklist

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

What's Wrong?

I have an MCP server configured in claude_desktop_config.json using mcp-remote. The logs clearly show the server connects successfully, tools/list is called, and the tool is returned in the response — but when I start a conversation, Claude says the tool is not available and cannot call it.

The tool name is conlucra_chatbot, served from https://live.nocodebots.ai/mcp.
I have logs showing the full successful handshake including the tools/list response containing the tool definition, but Claude still responds as if it doesn't exist and throws a "Tool not found" error when it tries to call it.

This makes MCP via mcp-remote completely unusable.

What Should Happen?

Expected:

Claude can call the registered tool

Actual:

"Tool not found"

Error Messages/Logs

"The tool is definitely being registered correctly — the desktop app receives it, but then Claude (me) isn't being given access to it when the conversation starts. This looks like a bug in the Claude desktop app itself where MCP tools from remote servers via mcp-remote aren't being surfaced to the model.
I'd suggest reporting this to Anthropic. You can do that via the thumbs down button, or at https://support.anthropic.com."

From ~/Library/Logs/Claude/mcp-server-conlucra.log:

2026-02-20T14:39:03.164Z [conlucra] [info] Initializing server... { metadata: undefined }
2026-02-20T14:39:03.265Z [conlucra] [info] Using MCP server command: /usr/local/bin/npx with args and path: {
  metadata: {
    args: [
      '-y', 
      'mcp-remote',
      'https://live.nocodebots.ai/mcp',
      [length]: 3
    ],
    paths: [
      '/Users/dmb/.nvm/versions/node/v20.19.4/bin',
      '/Users/dmb/.nvm/versions/node/v22.18.0/bin',
      '/usr/local/bin',
      '/opt/local/bin',
      '/usr/bin',
      '/bin',
      '/usr/sbin',
      '/sbin',
      [length]: 8
    ] 
  }   
} %o
2026-02-20T14:39:03.266Z [conlucra] [info] Server started and connected successfully { metadata: undefined }
2026-02-20T14:39:03.489Z [conlucra] [info] Message from client: {"method":"initialize","params":{"protocolVersion":"2025-11-25","capabilities":{"extensions":{"io.modelcontextprotocol/ui":{"mimeTypes":["text/html;profile=mcp-app"]}}},"clientInfo":{"name":"claude-ai","version":"0.1.0"}},"jsonrpc":"2.0","id":0} { metadata: undefined }
[47936] Using automatically selected callback port: 6240
[47936] Discovering OAuth server configuration...
[47936] [47936] Connecting to remote server: https://live.nocodebots.ai/mcp
[47936] Using transport strategy: http-first
[47936] Connected to remote server using StreamableHTTPClientTransport
[47936] Local STDIO server running
[47936] Proxy established successfully between local STDIO and remote StreamableHTTPClientTransport
[47936] Press Ctrl+C to exit
[47936] [Local→Remote] initialize
[47936] {
  "jsonrpc": "2.0",
  "id": 0,
  "method": "initialize",
  "params": {
    "protocolVersion": "2025-11-25",
    "capabilities": {
      "extensions": {
        "io.modelcontextprotocol/ui": {
          "mimeTypes": [
            "text/html;profile=mcp-app"
          ]
        }
      }
    },
    "clientInfo": {
      "name": "claude-ai (via mcp-remote 0.1.37)",
      "version": "0.1.0"
    } 
  }   
}   
[47936] [Remote→Local] 0
2026-02-20T14:39:06.170Z [conlucra] [info] Message from server: {"jsonrpc":"2.0","id":0,"result":{"protocolVersion":"2025-03-26","serverInfo":{"name":"conlucra-mcp-jsonrpc-bridge","version":"4.0.0-streamable-http"},"capabilities":{"tools":{"listChanged":false},"logging":{}}}} { metadata: undefined }
2026-02-20T14:39:06.171Z [conlucra] [info] Message from client: {"method":"notifications/initialized","jsonrpc":"2.0"} { metadata: undefined }
[47936] [Local→Remote] notifications/initialized
2026-02-20T14:39:06.173Z [conlucra] [info] Message from client: {"method":"tools/list","params":{},"jsonrpc":"2.0","id":1} { metadata: undefined }
[47936] [Local→Remote] tools/list
[47936] [Remote→Local] 1
2026-02-20T14:39:06.268Z [conlucra] [info] Message from server: {"jsonrpc":"2.0","id":1,"result":{"tools":[{"name":"conlucra_chatbot","description":"Run a Conlucra chatbot via ops reset|next|previous. Full state is stored in S3 keyed exactly by session_id.","inputSchema":{"type":"object","additionalProperties":false,"properties":{"cbkey":{"type":"string"},"op":{"type":"string","enum":["reset","next","previous"]},"session_id":{"type":"string"},"answer":{}},"required":["cbkey","op"]}}],"nextCursor":null}} { metadata: undefined }

Steps to Reproduce

Add an mcp-remote server to claude_desktop_config.json
Start Claude desktop — server connects and tool registers successfully per logs
Start a new conversation and ask Claude to use the tool
Claude cannot see or call the tool

Claude Model

Sonnet (default)

Is this a regression?

I don't know

Last Working Version

This is the first version.

Claude Code Version

Version 1.1.3770 (f7f585)

Platform

Other

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

Image Image

Metadata

Metadata

Assignees

No one assigned

    Labels

    duplicateThis issue or pull request already exists

    Type

    No type
    No fields configured for issues without a type.

    Projects

    No projects

    Milestone

    No milestone

    Relationships

    None yet

    Development

    No branches or pull requests

    Issue actions