Indexed
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Debugging MCP

Diagnose and fix the most common Indexed MCP server issues — startup errors, PATH problems, and connection failures.

Debugging MCP

By the end of this guide, you will be able to diagnose and resolve the most common MCP server issues: startup failures, PATH problems, tools not appearing in clients, and connection errors.

Prerequisites

  • Indexed installed
  • At least one collection created (indexed index inspect should show results)

Start the Server Manually

The first debugging step is always to start the MCP server directly and read the output. This isolates problems that would otherwise be invisible inside a client.

Terminal
indexed mcp run

Healthy startup:

Indexed MCP server started
Transport: stdio
Collections available: my-docs, eng-tickets
Waiting for client connection...

Startup error examples:

Error: No collections found. Create one with 'indexed index create'.

→ You haven't indexed any documents yet. Run indexed index create files -c my-docs -p ./docs first.

Error: Configuration not found. Run 'indexed config init' first.

→ The workspace hasn't been initialized. Run indexed config init from the directory where you want .indexed/ (see Quick Start), then indexed init for models if needed.

Press Ctrl+C to stop the server once you've confirmed it starts.

Use the MCP Inspector

indexed mcp dev starts the MCP server with a built-in browser UI that lets you call search and search_collection directly, without involving any client:

Terminal
indexed mcp dev
Indexed MCP dev server started
Opening MCP Inspector at http://127.0.0.1:5173

In the browser UI:

  1. Select the search tool from the tool list
  2. Enter a query value (e.g., "authentication guide")
  3. Click Run

A successful call and response:

// Call
{ "query": "authentication guide" }

// Response
{
  "results": [
    {
      "collection": "my-docs",
      "document": "auth-setup.md",
      "chunk": "To configure SSO authentication, first set up your identity provider...",
      "score": 0.82
    }
  ]
}

If the call succeeds here but the client still doesn't work, the problem is in the client configuration — not in Indexed itself.

Check Your PATH

The most common failure mode for pipx installs is that the indexed binary is on a PATH that your client doesn't inherit. Verify the binary is findable:

Terminal
which indexed
echo $PATH

Expected output of which indexed:

/Users/you/.local/bin/indexed

If which indexed returns nothing, the binary isn't on your PATH. Run pipx ensurepath and restart your shell, then try again.

If which indexed returns a path but your client still can't find it, use the full absolute path in your client config instead of "command": "indexed":

{
  "mcpServers": {
    "indexed": {
      "command": "/Users/you/.local/bin/indexed",
      "args": ["mcp", "run"]
    }
  }
}

Common Errors and Fixes

ErrorLikely CauseFix
command not found: indexedindexed not on PATH inherited by clientUse full binary path in client config; run which indexed to find it
No collections foundNo collections have been createdRun indexed index create <connector> -c <name> ...
Connection refusedServer not started, or wrong transport/portRun indexed mcp run manually to check startup; verify transport matches client expectations (remember -h on mcp run is --host, not help — use --help for usage)
Tools not appearing in clientClient didn't restart after config change, or config has JSON errorsFully quit and relaunch the client; validate JSON syntax
Slow first responseEmbedding model loading into memoryNormal behavior on first query; subsequent queries are fast

HTTP Transport Testing

If you're using the HTTP transport (e.g., for Docker or remote access), verify the server independently using curl before involving any client:

Terminal
indexed mcp run --transport http --port 8000

In another terminal:

Terminal
curl -s http://127.0.0.1:8000/tools | python3 -m json.tool

A working response lists the available tools:

{
  "tools": [
    { "name": "search", "description": "Search across all collections" },
    { "name": "search_collection", "description": "Search a specific collection" }
  ]
}

If curl fails but the server started without errors, check your firewall or that the port isn't already in use:

Terminal
lsof -i :8000

What's Next