Agent SDK reference - TypeScript changedagent-sdk/typescript
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16021602Claude Code echoes the answered message's `uuid` on three kinds of frame:
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16041604* **The result**: every result of a turn that answered a message you sent. Every such result carries it on Agent SDK v0.3.265 or later. Before v0.3.265, the success result of a turn that a regular message started lacked it when the turn sent no API request or ended with a deferred tool call. Before v0.3.246, error results lacked it too, and before v0.3.216 every result did.
1605* **The turn's first reply**: the first [assistant message](#sdkassistantmessage), or with `includePartialMessages` the first [stream event](#sdkpartialassistantmessage) whose `event.type` isn't `ping`, so you can bind the reply before the result arrives. When a turn streams nothing, Claude Code sets it on the first assistant message instead. The first-reply echo requires Agent SDK v0.3.246 or later. When the message the turn is answering changes mid-turn, the first reply after the change carries the field too, on Agent SDK v0.3.265 or later; earlier versions set it on one reply frame per turn.
1605* **The turn's first reply**: the first [assistant message](#sdkassistantmessage), and with `includePartialMessages` also the first [stream event](#sdkpartialassistantmessage) whose `event.type` isn't `ping`, so you can bind the reply before the result arrives. The first-reply echo requires Agent SDK v0.3.246 or later. Before v0.3.269, with `includePartialMessages`, Claude Code set it on that first stream event only, or on the first assistant message when the turn streamed nothing. When the message the turn is answering changes mid-turn, the first reply after the change carries the field too, on Agent SDK v0.3.265 or later; earlier versions set it on one reply frame per turn.
16061606* **Every [`thinking_tokens`](#sdkthinkingtokensmessage) frame of the turn**: so you can attribute thinking progress to the message you sent without waiting for the turn's first reply. Requires Agent SDK v0.3.260 or later.
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16081608Claude Code omits the field in these cases:
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54545454| `network` | [`SandboxNetworkConfig`](#sandboxnetworkconfig) | `undefined` | Network-specific sandbox configuration |
54555455| `filesystem` | [`SandboxFilesystemConfig`](#sandboxfilesystemconfig) | `undefined` | Filesystem-specific sandbox configuration for read/write restrictions |
54565456| `ignoreViolations` | `Record<string, string[]>` | `undefined` | Map of command substrings, or `*` for every command, to substrings of the violation text to ignore, such as `{ "*": ['/etc/hosts'] }`; see [`sandbox.ignoreViolations`](/docs/en/settings-reference#sandbox-ignoreviolations) |
5457| `enableWeakerNestedSandbox` | `boolean` | `false` | Enable a weaker nested sandbox for compatibility |
5458| `ripg
5457| `enableWeakerNestedSandbox`
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