strands.tools.mcp.mcp_types

Type definitions for MCP integration.

MCPToolResult

class MCPToolResult(ToolResult)

Defined in: src/strands/tools/mcp/mcp_types.py:50

Result of an MCP tool execution.

Extends the base ToolResult with MCP-specific structured content support. The structuredContent field contains optional JSON data returned by MCP tools that provides structured results beyond the standard text/image/document content.

Attributes:

• structuredContent - Optional JSON object containing structured data returned by the MCP tool. This allows MCP tools to return complex data structures that can be processed programmatically by agents or other tools.
• metadata - Optional arbitrary metadata returned by the MCP tool. This field allows MCP servers to attach custom metadata to tool results (e.g., token usage, performance metrics, or business-specific tracking information).
• isError - Whether the MCP tool reported an application-level error via CallToolResult.isError. True means the tool executed but its logic returned a failure. Absent when the tool succeeded or when the error was a protocol/client exception rather than a tool-reported failure, letting callers distinguish application errors from transport/protocol errors.