MCP Server for Find Reference

MCP Server for Find Reference

Configuring the MCP server

1. Add the server to AMP using http://localhost:3001 and name it get-text-matches.
2. Run the server using node server.js.

Current functionality

The MCP server supports two tools. Both tools will run recursively over all files in the given directory.

The get-text-matches tool returns a list of {file, line, column} where an exact text match is found.

The get-parse-tree tool returns the metadata from a parse tree for a given string.

Testing the MCP server

Sample Directory

To get started, run this command in a new directory to make a sample client file:

<pre>mkdir client && cd client && echo -e "import { temp_x } from './scope.js';\n\ntemp_x = 5;\n\ntemp_x = 7 + 4;\n\nconsole.log(temp_x);" > include_scope.js && echo -e "let temp_x = 5;\n\ntemp_x = 7 + 4;\n\nconsole.log(temp_x);" > exclude_scope.js && echo -e "let temp_x = \"Hello\";\n\nif(true){\n let temp_x = 10;\n console.log(temp_x);\n}\n\ntemp_x = \"World\";\n\n{\n temp_x;\n}" > scope.js</pre>

get-text-matches

Prompt the MCP server with the following command:

use the get-text-match tool to find temp_x, specify the full path

get-parse-tree

Prompt the MCP server with the following command:

use the get-parse-tree tool to find temp_x, specify the full path

This allows follow-up prompts such as:

what are the different node types of temp_x

Or

what type of variable is temp_x

Or

where is temp_x defined in include_scope and where is temp_x defined in exclude_scope

These prompts can be combined into something more complex, such as what variable type is temp_x in the scope of include_scope

Note: the client will try to find this information itself, since it has direct access to the file in question, so it is currently necessary to tell it to use the get-text-match and get-parse-tree tools.

Troubleshooting

If the MCP server selects the wrong tool, you can tell it to specifically not use a tool. For example:

use the parse tree tool, not get text, to find temp_x, specify the full path

It is not always necessary to tell it to specify the full path, but occasionally it will decide to use . as the directory instead of the full path, which the server needs.

The MCP server must trust the client to tell it what local directory to check. If desired, you can hard code the path.

Functionality for the future

1. Returning case-insensitive matches.
2. Allowing ignorable files/folders. For example, searching for "import" in a directory with node_modules goes over the token limit.
3. Making a prettier and more concise output for the parse tree.