unpack_sources
Extract original source files and their content from a source map to map JavaScript error stack traces back to original code for debugging.
Instructions
Unpack Source Map Sources
This tool extracts all source files and their content from a source map.
Parameters:
sourceMapUrl: The URL of the source map file to unpack
Returns:
A JSON object containing:
sources: Object with source file paths as keys and their content as values
sourceRoot: The source root path from the source map
file: The original file name
totalSources: Total number of source files found
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| sourceMapUrl | Yes | The URL of the source map file to unpack |
Implementation Reference
- src/tools.ts:328-338 (handler)MCP tool handler function for 'unpack_sources'. Awaits the parser instance and calls its unpackSources method, then returns the result as formatted JSON text content.
handler: async ({ sourceMapUrl }, getParser) => { const parser = await getParser(); const result = await parser.unpackSources(sourceMapUrl); return { content: [{ type: "text", text: JSON.stringify(result, null, 2) }], } } - src/tools.ts:323-327 (schema)Zod input schema for the 'unpack_sources' tool, validating the required sourceMapUrl parameter.
schema: { sourceMapUrl: z.string({ description: "The URL of the source map file to unpack", }), }, - src/tools.ts:348-354 (registration)Registration loop in registerTools function that calls server.tool() for 'unpack_sources' (and other tools) if it passes the filter check.
toolDefinitions.forEach(tool => { if (shouldRegisterTool(tool.name, options.toolFilter)) { server.tool(tool.name, tool.description, tool.schema, async (params) => { return tool.handler(params, getParser); }); } }); - src/parser.ts:415-451 (helper)Core helper method in Parser class that fetches and parses the source map JSON to extract all source file paths and contents (from sourcesContent if present, else null), returning structured result.
public async unpackSources(sourceMapUrl: string) { validateUrl(sourceMapUrl); try { const sourceMapContent = await this.fetchSourceMapContent(sourceMapUrl); const sourceMap = JSON.parse(sourceMapContent); if (!sourceMap.sources || !Array.isArray(sourceMap.sources)) { throw new Error("Invalid source map: missing or invalid sources array"); } const result: Record<string, string | null> = {}; // Extract sources from sourcesContent if available if (sourceMap.sourcesContent && Array.isArray(sourceMap.sourcesContent)) { sourceMap.sources.forEach((source: string, index: number) => { result[source] = sourceMap.sourcesContent[index] || null; }); } else { // If no sourcesContent, list sources with null content sourceMap.sources.forEach((source: string) => { result[source] = null; }); } return { sources: result, sourceRoot: sourceMap.sourceRoot || null, file: sourceMap.file || null, totalSources: sourceMap.sources.length }; } catch (error) { throw new Error("unpack sources error: " + (error instanceof Error ? error.message : error), { cause: error, }); } }