Constant MEMORY_READ_TOOL 

pub(crate) const MEMORY_READ_TOOL: &str = r#"{
  "name": "MemoryRead",
  "description": "Read one of your own native memory (brain) markdown files by filename. Returns its content. Get valid filenames from MemoryList.",
  "inputSchema": {
    "type": "object",
    "properties": {
      "filename": { "type": "string", "description": "The memory file to read (from MemoryList)" }
    },
    "required": ["filename"]
  }
}"#;