Under the hood
Task summary docs now spell out that local agents give a model-written progress summary and MCP tasks give the server's status.
The summary field on task status objects is now documented to clarify its source: for a local_agent task it is a model-generated progress summary, shown only when agentProgressSummaries is enabled, while for a backgrounded mcp_task it is the MCP server's own status message and is always emitted.
Names in the bundleagentProgressSummaries
Documented inclaude-code/agent-sdk/typescript