Method execute

src/tools/filesystem/read.ts:22–133

(args: z.infer<typeof ArgsSchema>, ctx: ToolContext)

  argsSchema = ArgsSchema;

  async execute(args: z.infer<typeof ArgsSchema>, ctx: ToolContext): Promise<ToolResult> {
    const abs = path.isAbsolute(args.path) ? args.path : path.resolve(ctx.cwd, args.path);

    let buf: Buffer;
    try {
      const stat = await fs.stat(abs);
      if (stat.isDirectory()) {
        return { content: `[ERROR] ${args.path} is a directory. Use ls to list its contents.`, isError: true };
      }
      if (stat.size > 5 * 1024 * 1024) {
        return {
          content: `[ERROR] File ${args.path} is ${(stat.size / 1024 / 1024).toFixed(1)}MB which is too large. Use offset/limit to read in chunks, or use grep to find specific content.`,
          isError: true,
        };
      }
      // Fast-path reject for known binary extensions
      if (hasBinaryExtension(abs)) {
        return {
          content: `[BINARY_FILE] ${args.path} is a binary file by extension (${(stat.size / 1024).toFixed(1)}KB). I cannot read binary content as text. If you need metadata, use shell with: file '${path.basename(abs)}' or stat. If you need byte-level inspection, use: hexdump -C '${path.basename(abs)}' | head.`,
          isError: true,
        };
      }
      buf = await fs.readFile(abs);
    } catch (e: any) {
      if (e.code === 'ENOENT') {
        const { notFoundWithSuggestions } = await import('./suggest-paths.js');
        const msg = await notFoundWithSuggestions(
          ctx.cwd, args.path,
          `[FILE_NOT_FOUND] ${args.path} does not exist.${outsideCwdHint(args.path, abs, ctx.cwd)}`,
        );
        return { content: msg, isError: true };
      }
      return { content: `[ERROR] Failed to read ${args.path}: ${e.message}`, isError: true };
    }

    // Content-sniff for binary
    if (isBinaryBuffer(buf)) {
      return {
        content: `[BINARY_FILE] ${args.path} appears to be binary content (${(buf.length / 1024).toFixed(1)}KB, contains null bytes or non-printable bytes). I cannot read it as text. Use shell with hexdump/file/strings for binary inspection.`,
        isError: true,
      };
    }

    const content = buf.toString('utf-8');

    const allLines = content.split('\n');

    // Symbol-targeted read: resolve a declaration by name via the outline and
    // return exactly that range. Lets the model say symbol="HomePage" instead of
    // guessing line numbers on a big file.
    if (args.symbol) {
      const { fileOutline } = await import('../../context/file-outline.js');
      const rel = path.relative(ctx.cwd, abs) || path.basename(abs);
      const outline = await fileOutline(rel, content);
      const want = args.symbol.toLowerCase();
      const hit = outline.find(e => e.symbol.toLowerCase() === want)
        ?? outline.find(e => e.symbol.toLowerCase().endsWith('.' + want))
        ?? outline.find(e => e.symbol.toLowerCase().includes(want));