reference changedmanaged-agents/reference
Nearest release: v2.1.257, published under an hour before this site recorded the change. Shown because the two are within 24 hours of each other. Nothing here says the release caused the edit.
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Lines+3added
Lines−3removed
From line
74
where the diff opens
First seen
14 Aug 2026
this site's first read of the page
Recorded edits19to this page, all time
The whole hunk
from line 74, old and new numbered
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from line 74
7474 </Tab>
7575
7676 <Tab title="System events">
77 | Type | Description |
78 | ---------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
79 | `system.message` | Append privileged system-level context that applies to the accompanying turn and all subsequent turns. Supported on Claude Opus 4.8, Claude Fable 5, Claude Mythos 5, and Claude Opus 5; on an unsupported primary model the event is rejected with `model_does_not_support_mid_conversation_system`. |
77 | Type | Description |
78 | ---------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
79 | `system.message` | Append privileged system-level context that applies to the accompanying turn and all subsequent turns. Supported on Claude Fable 5.1, Claude Mythos 5.1, Claude Fable 5, Claude Mythos 5, Claude Opus 5, and Claude Opus 4.8. On an unsupported primary model the event is rejected with `model_does_not_support_mid_conversation_system`. |
8080 </Tab>
8181
8282 <Tab title="Event deltas">
No line in this hunk matches that.