Fix: use blob field for binary resources in sandbox container #252
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Binary content (images, etc.) was incorrectly using 'text' field, causing MCP hosts like Claude Desktop to display base64 strings as text messages, flooding the context window. Changed to use 'blob' field for binary data per MCP 2025-06-18 spec.
This was referenced Nov 6, 2025
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Binary content (images, etc.) in
container_file_readtool was using thetextfield, causing MCP hosts like Claude Desktop to display base64-encoded strings as both text message and image content in the conversation, which floods the context window with meaningless data.This PR changed
container_file_readto use theblobfield for binary data instead oftextfield, in compliance with the MCP 2025-06-18 specification for resource contents.Per MCP spec:
textfieldblobfield