Under the hood
Deferred MCP tool tracking now reports when a deferred tool's entry differs from what was actually sent.
Tracking of MCP tools declared with defer_loading now records whether a deferred tool's entry differs from what was actually sent when referenced, reporting via the mcp_kept_deferred_tools telemetry event, including a dedicated failure case for this bookkeeping.
Names in the bundledefer_loading
The entry above is what we published on the day. These lines were added later, as Anthropic's own pages caught up, and they sit beside the original rather than replacing it.
Confirmed since
Anthropic's documentation has since written up defer_loading, on Batches.
- `defer_loading: optional boolean or null`api/messages/batches see the edit
One source agreesOne thing we can check says the same as this entry.
Anthropic's documentation agrees
Anthropic's documentation has since written up defer_loading, on Batches.