Create a binary payload carried as base64 text.
Base64-encoded bytes.
MIME type of the binary payload.
Tool result with base64 text and binary MIME metadata.
Prefer a raw CallToolResult with an appropriate content
block, or a resource { contents: [{ uri, mimeType, blob }] }.
Deprecated
Prefer raw CallToolResult, ReadResourceResult, or GetPromptResult returns. These helpers remain for upgrade compatibility and map to the official wire envelopes.