PDF Redaction MCP Server

Instructions

Implementation Reference

• src/redact_mcp/server.py:288-358 (handler)

  The handler function decorated with @mcp.tool that implements the save_redacted_pdf tool. It applies all pending redaction annotations to the loaded PDF document and saves it to a new file, either at a specified output_path or by appending '_redacted' to the original filename.

  @mcp.tool
  async def save_redacted_pdf(
      pdf_path: Annotated[str, Field(description="Path to the loaded PDF file")],
      output_path: Annotated[str | None, Field(
          description="Optional output path. If not provided, appends '_redacted' to the original filename"
      )] = None,
      ctx: Context = None
  ) -> str:
      """Apply all redactions and save the redacted PDF.
      
      This tool applies all pending redaction annotations to the PDF and saves it.
      By default, it saves to a new file with '_redacted' appended to the original
      filename.
      
      Args:
          pdf_path: Path to the PDF file (must be already loaded)
          output_path: Optional custom output path. If not provided, saves as
                      '<original_name>_redacted.pdf'
          ctx: MCP context for logging
          
      Returns:
          Path to the saved redacted PDF
          
      Raises:
          ToolError: If the PDF is not loaded or save fails
      """
      try:
          path = Path(pdf_path).resolve()
          path_str = str(path)
          
          await ctx.info(f"Saving redacted PDF: {path}")
          
          # Check if PDF is loaded
          if path_str not in _loaded_pdfs:
              raise ToolError(
                  f"PDF not loaded. Please load it first using load_pdf: {path}"
              )
          
          doc = _loaded_pdfs[path_str]
          
          # Determine output path
          if output_path:
              out_path = Path(output_path).resolve()
          else:
              # Append '_redacted' to the original filename
              out_path = path.parent / f"{path.stem}_redacted{path.suffix}"
          
          # Count total redactions before applying
          total_redactions = 0
          for page in doc:
              # Apply redactions on this page
              redact_count = page.apply_redactions()
              if redact_count:
                  total_redactions += 1  # Note: apply_redactions returns True if any were applied
          
          # Save the document
          doc.save(str(out_path))
          
          await ctx.info(f"Saved redacted PDF to: {out_path}")
          
          return (
              f"Successfully applied redactions and saved to: {out_path}\n"
              f"Redactions applied on {total_redactions} page(s)."
          )
          
      except ToolError:
          raise
      except Exception as e:
          await ctx.error(f"Failed to save redacted PDF: {str(e)}")
          raise ToolError(f"Failed to save redacted PDF: {str(e)}")