Two tools with complete schemas and descriptions in Russian. Both tools have proper Zod schema definitions with type constraints (min/max for limit, int/positive for id). Descriptions are moderately detailed (100-200 chars) and explain purpose and return values. However, parameter descriptions lack actionable format guidance (e.g., no enum for format values in download_book despite listing 'fb2, epub, mobi, pdf, txt, rtf, html'). Error handling is present but generic. No tool annotations (readOnlyHint/destructiveHint). Output structure is text-only rather than structured JSON, limiting downstream tool chaining.

• Convert download_book 'format' parameter to enum: z.enum(['fb2', 'epub', 'mobi', 'pdf', 'txt', 'rtf', 'html']).describe('Format: one of fb2, epub, mobi, pdf, txt, rtf, html'). This prevents hallucinated formats.
• Return structured JSON from both tools. search_books should return {books: [{id, title, author, formats: string[], size: string, downloads: number}], total: number}. download_book should return {path: string, size: number, format: string}. This enables agent chaining.
• Add tool annotations via server.tool() options: search_books with readOnlyHint=true, download_book with destructiveHint=true. Agents need to know which tools have side effects.
• Enhance error messages with recovery guidance. E.g., 'Format "xyz" not supported. Available: fb2, epub, mobi, pdf, txt, rtf, html' or 'Book ID 999 not found. Try search_books() to find valid IDs.'
• Add offset/limit pagination to search_books. Accept optional offset parameter (default 0) and return total_count so agent can iterate through large result sets.