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---

# pydantic\_ai.realtime.lifecycle

The lifecycle events a [`RealtimeConnection`](https://pydantic.dev/docs/ai/api/realtime/codec/#pydantic_ai.realtime.codec.RealtimeConnection) yields with its [codec events](https://pydantic.dev/docs/ai/api/realtime/codec/), for implementing a realtime provider: which response, spoken turn, and input each codec event is about. Most users only need the session-level API in [`pydantic_ai.realtime`](https://pydantic.dev/docs/ai/api/pydantic-ai/realtime/).

The lifecycle events a realtime connection yields, for implementing a realtime provider.

The [codec vocabulary](https://pydantic.dev/docs/ai/api/realtime/codec/#pydantic_ai.realtime.codec) says _what_ the model said, but not which response it belongs to, when that response began or ended, or which of the session's inputs it answers. Only the connection sees the provider frames that settle those questions, so a [`RealtimeConnection`](https://pydantic.dev/docs/ai/api/realtime/codec/#pydantic_ai.realtime.codec.RealtimeConnection) states them outright, interleaved with its codec events in the [`RealtimeFrame`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.RealtimeFrame)s it yields from [`frames()`](https://pydantic.dev/docs/ai/api/realtime/codec/#pydantic_ai.realtime.codec.RealtimeConnection.frames):

-   a response is bracketed by exactly one [`ResponseStarted`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.ResponseStarted) and one [`ResponseEnded`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.ResponseEnded), and its content arrives only in between;
-   [`ResponseStarted.answers`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.ResponseStarted.answers) names the inputs whose reply the response is, which is what [`wait_for_reply()`](https://pydantic.dev/docs/ai/api/pydantic-ai/realtime/#pydantic_ai.realtime.RealtimeSession.wait_for_reply) waits for, and [`AnswersRevised`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.AnswersRevised) corrects them as the connection learns better: `claimed` while the response is under way, `released` until its reply (tool rounds included) is over;
-   a spoken user turn starts with [`UserTurnStarted`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.UserTurnStarted), joins the conversation with [`UserTurnEnded`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.UserTurnEnded), and gets no more audio or transcript after [`UserTurnClosed`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.UserTurnClosed) (which drops one that hadn't joined);
-   [`InputAdded`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.InputAdded) marks where an input joined the provider's conversation, so history can follow the provider's order;
-   [`InputLost`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.InputLost) and [`ResponseRequestRefused`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.ResponseRequestRefused) settle the inputs no response will ever answer, and [`ToolCallsAbandoned`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.ToolCallsAbandoned) the tool calls whose results none will;
-   [`OutputItemDetails`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.OutputItemDetails) keeps what the provider says about an output item on the part it makes, and [`OutputItemCut`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.OutputItemCut) records that the listener heard only part of it, even after its response ended.

An input is identified by its position among every [`send()`](https://pydantic.dev/docs/ai/api/realtime/codec/#pydantic_ai.realtime.codec.RealtimeConnection.send) call made on the connection, counting from `0`, as [`InputRejected.input_index`](https://pydantic.dev/docs/ai/api/realtime/codec/#pydantic_ai.realtime.codec.InputRejected.input_index) identifies it.

A protocol that identifies its responses, turns, and inputs (as the OpenAI Realtime API does) is best translated directly. One that identifies none of them, like Gemini Live and OpenAI GPT-Live, can have [`InferredLifecycle`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.InferredLifecycle) work them out from the order of what the connection sends and receives.

### LifecycleEvent

What a connection says about the responses, spoken turns, and inputs its codec events are about.

The base of the lifecycle events below, so `isinstance(event, LifecycleEvent)` tells one apart from a codec event in a [`RealtimeFrame`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.RealtimeFrame).

### ResponseStarted

**Bases:** `LifecycleEvent`

A response began: exactly once per response, before any of its content.

#### Attributes

##### response\_id

The response's id: the provider's, or one the connection made up when the provider gives none.

**Type:** [`str`](https://docs.python.org/3/builtins/stdtypes.html#str)

##### answers

The inputs whose request for a response this response satisfies.

Empty for a response the provider started on its own, such as a server-VAD reply to a spoken turn.

**Type:** [`tuple`](https://docs.python.org/3/builtins/stdtypes.html#tuple)\[`InputId`, ...\] **Default:** `()`

##### basis

Whether the provider said which inputs `answers` are (`'protocol'`), or the connection worked it out from the requests it had outstanding (`'inferred'`).

**Type:** `AnswersBasis` **Default:** `'protocol'`

##### user\_turn\_id

The spoken user turn a response the provider started on its own is replying to, when known.

**Type:** [`str`](https://docs.python.org/3/builtins/stdtypes.html#str) | [`None`](https://docs.python.org/3/builtins/constants.html#None) **Default:** `None`

##### continues

The response this one carries on from: one the provider ended while saying the exchange isn't over (Gemini's `interaction_status=IN_PROGRESS`), so whatever waits for that one's reply waits for this one too.

**Type:** [`str`](https://docs.python.org/3/builtins/stdtypes.html#str) | [`None`](https://docs.python.org/3/builtins/constants.html#None) **Default:** `None`

##### provider\_id

Whether `response_id` is the provider's own id, which history records, rather than one the connection made up for a protocol that gives its responses none.

**Type:** [`bool`](https://docs.python.org/3/builtins/functions.html#bool) **Default:** `True`

### AnswersRevised

**Bases:** `LifecycleEvent`

Which inputs a response answers turned out different from what its `ResponseStarted` said.

A connection that works its responses' `answers` out (`basis='inferred'`) can learn better as the response goes on: GPT-Live answers text sent mid-reply in the speech already under way, and Gemini cuts off a reply that an input reaches mid-generation, leaving that input to the next one. `claimed` is valid while the response is under way, `released` until its reply (tool rounds included) is over.

It moves no message: history keeps every input where it joined the conversation.

#### Attributes

##### claimed

Inputs still owed a reply that this response answers after all. Only while it is under way (before its `ResponseEnded`).

**Type:** [`tuple`](https://docs.python.org/3/builtins/stdtypes.html#tuple)\[`InputId`, ...\] **Default:** `()`

##### released

Inputs this response was said to answer that it doesn't: a later response answers them, naming them in its `ResponseStarted.answers` (or in a `claimed` of its own).

Before its `ResponseEnded`, or after it while its reply goes on: in the answer to its tool calls, say, which the provider can cancel when an input cuts the turn off.

**Type:** [`tuple`](https://docs.python.org/3/builtins/stdtypes.html#tuple)\[`InputId`, ...\] **Default:** `()`

### InferredLifecycle

Works out a connection's lifecycle events from the order of what it sends and receives.

For a protocol that identifies no responses, spoken turns, or inputs, as Gemini Live and OpenAI GPT-Live don't. The connection, in its [`send`](https://pydantic.dev/docs/ai/api/realtime/codec/#pydantic_ai.realtime.codec.RealtimeConnection.send), sends each input inside [`sending`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.InferredLifecycle.sending) (which reports it, and reports it failed if sending it raises) and returns what the send settled ([`take_pending`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.InferredLifecycle.take_pending)). It passes the codec events each provider message makes through [`frame_for`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.InferredLifecycle.frame_for) to get the frame to yield, and reports a dropped connection ([`connection_lost`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.InferredLifecycle.connection_lost)). A connection whose codec events are an async iterable of their own can have [`frames`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.InferredLifecycle.frames) do the last two.

What it works out:

-   A response starts with its first output (audio, a transcript, a native tool part, a tool call), and ends at its [`ResponseDone`](https://pydantic.dev/docs/ai/api/realtime/codec/#pydantic_ai.realtime.codec.ResponseDone); a response that makes tool calls ends with them, or, when they are reported with `response_usage_follows`, at the usage report that follows them. Its id is made up, so it is recorded as no provider's (`ResponseStarted.provider_id=False`).
-   A response answers every input that asked for one (a `str` turn, a tool result, a `CreateResponse`) and wasn't answered when it started (`ResponseStarted.basis='inferred'`).
-   A spoken turn starts with its first input transcript, joins the conversation as the reply to it starts, and has its whole transcript once that reply ends, unless the transcript is marked final before. A turn the provider identifies (its transcripts carry an `item_id`) is named by that id, and waits for its final transcript. Without input transcription, audio sent since the last reply is a turn of its own, with no transcript, when the model next replies to speech.
-   An input joins the conversation when it is sent, unless a reply is under way or owed: it then reached the provider while the model was working on that reply, and follows it.
-   A dropped connection loses the response under way and every reply still owed.

These are the defaults; a provider that departs from them gets a subclass overriding these extension points:

-   [`transcripts_lag_replies`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.InferredLifecycle.transcripts_lag_replies) (`True`): whether the provider transcribes the user's words after the model started answering them.
-   [`audio_starts_response`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.InferredLifecycle.audio_starts_response) (`True`): whether output audio is the model speaking, so a response starts with it.
-   [`untranscribed_audio_is_a_turn`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.InferredLifecycle.untranscribed_audio_is_a_turn) (`True`): whether audio the model replies to before any transcript of it came is a spoken turn of its own.
-   [`inputs_cut_off_replies`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.InferredLifecycle.inputs_cut_off_replies) (`False`): whether an input that reaches the provider mid-generation cuts the reply off, leaving it to the next.
-   [`takes_turn(codec)`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.InferredLifecycle.takes_turn) (`False`): whether a provider message has the model take the turn, whatever its output shows.

#### Attributes

##### transcripts\_lag\_replies

Whether the provider can transcribe the user's words after the model started answering them, as most do.

A transcript that starts while a reply nobody asked for is under way is then the speech that reply answers, rather than speech over it. A subclass for a provider that transcribes as the user speaks (and so reports speech over a reply while the reply is still going) sets it to `False`.

**Type:** [`bool`](https://docs.python.org/3/builtins/functions.html#bool) **Default:** `True`

##### audio\_starts\_response

Whether output audio is the model speaking, so a response starts with it.

A subclass for a provider whose output is a continuous track, silent between replies, sets it to `False`, and says where the model takes the turn with `takes_turn` instead.

**Type:** [`bool`](https://docs.python.org/3/builtins/functions.html#bool) **Default:** `True`

##### inputs\_cut\_off\_replies

Whether an input that reaches the provider while it generates a reply cuts that reply off.

The next reply then answers the input, so a reply cut off (`ResponseStarted` through a cancelled `ResponseEnded`) answers only the oldest input it was taken to answer, as that one started it, or none if it said nothing; and a reply whose tool calls the provider cancels answers only the oldest too. That is, unless the provider heard the user start speaking after those inputs went out ([`speech_heard()`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.InferredLifecycle.speech_heard)): then the user may have cut the reply off, as ever. The rest are released ([`AnswersRevised.released`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.AnswersRevised.released)) to the next reply. A subclass for a provider that cuts its reply off this way (Gemini Live's 3.x models do) sets it to `True`.

**Type:** [`bool`](https://docs.python.org/3/builtins/functions.html#bool) **Default:** `False`

##### untranscribed\_audio\_is\_a\_turn

Whether audio the model replies to before any transcript of it came is a spoken turn of its own.

A subclass for a provider that replies to speech only once it has transcribed it (a cascaded pipeline, say) sets it to `False`, so audio no transcript names, like a microphone streaming before a greeting, makes no turn. Without input transcription (`transcribes=False`), audio is the only sign of speech, and always makes a turn.

**Type:** [`bool`](https://docs.python.org/3/builtins/functions.html#bool) **Default:** `True`

#### Methods

##### \_\_init\_\_

```python
def __init__(*, transcribes: bool = True) -> None
```

Track a connection's lifecycle.

###### Returns

[`None`](https://docs.python.org/3/builtins/constants.html#None)

###### Parameters

**`transcribes`** : [`bool`](https://docs.python.org/3/builtins/functions.html#bool) _Default:_ `True`

Whether the session has the user's speech transcribed: if not, audio alone makes a spoken turn. A setting of the session's (input transcription), not of the provider.

##### input\_sent

```python
def input_sent(content: RealtimeInput) -> InputId
```

An input is about to go out: note whether it asks for a reply, and where it joins the conversation.

Call it for every `send()`, before anything in it can fail, as the session numbers its inputs that way. Returns the input's id, for `input_failed` and `input_unanswerable`.

###### Returns

`InputId`

##### input\_failed

```python
def input_failed(input_id: InputId) -> None
```

The input never went out (its send raised): forget it.

###### Returns

[`None`](https://docs.python.org/3/builtins/constants.html#None)

##### input\_unanswerable

```python
def input_unanswerable(input_id: InputId) -> None
```

An input went (or was meant to go) out, but the provider will never reply to it.

###### Returns

[`None`](https://docs.python.org/3/builtins/constants.html#None)

##### sending

```python
def sending(content: RealtimeInput) -> Generator[InputId]
```

Report an input a connection's `send()` is sending, around the sending itself: yields the input's id.

It is [`input_sent`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.InferredLifecycle.input_sent) going in, and [`input_failed`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.InferredLifecycle.input_failed) if the block raises. The connection then returns [`take_pending()`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.InferredLifecycle.take_pending) (see the example in [Implementing a connection](https://pydantic.dev/docs/ai/api/pydantic-ai/realtime/)).

###### Returns

[`Generator`](https://docs.python.org/3/library/typing.html#typing.Generator)\[`InputId`\]

##### take\_pending

```python
def take_pending() -> list[LifecycleEvent]
```

The events the inputs sent since the last frame settled.

Where each joined the conversation, or that it will go unanswered. A connection returns them from [`send()`](https://pydantic.dev/docs/ai/api/realtime/codec/#pydantic_ai.realtime.codec.RealtimeConnection.send), so the session applies them before anything it reads next, and puts them at the head of a frame of its own (like the one it reports a reconnect in). [`frame_for()`](https://pydantic.dev/docs/ai/api/realtime/lifecycle/#pydantic_ai.realtime.lifecycle.InferredLifecycle.frame_for) takes any still waiting into the frame it makes.

###### Returns

[`list`](https://docs.python.org/3/glossary.html#term-list)\[`LifecycleEvent`\]

##### speech\_heard

```python
def speech_heard(*, after: InputId | None = None) -> None
```

The provider heard the user start speaking, which may cut a reply off (see `inputs_cut_off_replies`).

A `RealtimeInputSpeechStartEvent` says so; a connection whose provider reports speech some other way (Gemini Live's `voice_activity`) calls this, or every reply cut off is taken for one an input cut off. `after` is the id of the last input sent before the user started speaking, when the provider says where in the audio that was: `-1` if they started before any input, and by default every input sent so far, as the report may come late.

###### Returns

[`None`](https://docs.python.org/3/builtins/constants.html#None)

##### frame\_for

```python
def frame_for(codec: Sequence[RealtimeCodecEvent]) -> RealtimeFrame
```

The frame to yield for the codec events one provider message makes, with the lifecycle events around them.

###### Returns

`RealtimeFrame`

##### takes\_turn

```python
def takes_turn(codec: Sequence[RealtimeCodecEvent]) -> bool
```

Whether the provider message `codec` makes has the model take the turn, whatever its output shows.

An extension point for a subclass whose connection knows where the model takes the turn better than its output shows (see `audio_starts_response`): a response then starts with the message's audio, or after its events if it has none, if none is under way. `False` by default.

###### Returns

[`bool`](https://docs.python.org/3/builtins/functions.html#bool)

##### frames

`@async`

```python
def frames(events: AsyncIterable[RealtimeCodecEvent]) -> AsyncIterator[RealtimeFrame]
```

Frames for a connection's codec events, one event to a frame, ending with what the end of `events` loses.

For a connection whose codec events are an async iterable of their own, and end with the connection.

###### Returns

[`AsyncIterator`](https://docs.python.org/3/library/typing.html#typing.AsyncIterator)\[`RealtimeFrame`\]

##### connection\_lost

```python
def connection_lost() -> list[LifecycleEvent]
```

The connection dropped (and is being re-dialed, or is gone): nothing under way on it will finish.

A re-dial never resumes a generation, even when it resumes the session, so the response under way is lost, and so is every reply still owed. A spoken turn the model was about to answer is in the conversation all the same, with what transcript it has.

###### Returns

[`list`](https://docs.python.org/3/glossary.html#term-list)\[`LifecycleEvent`\]

### ResponseEnded

**Bases:** `LifecycleEvent`

A response ended: exactly once per started response, after all of its content and usage.

#### Attributes

##### finish\_reason

The normalized reason the provider finished the response, when it reported one.

**Type:** [`FinishReason`](https://pydantic.dev/docs/ai/api/pydantic-ai/messages/#pydantic_ai.messages.FinishReason) | [`None`](https://docs.python.org/3/builtins/constants.html#None) **Default:** `None`

##### provider\_details

The provider's raw terminal status details, when it reported any.

**Type:** [`dict`](https://docs.python.org/3/reference/expressions.html#dict)\[[`str`](https://docs.python.org/3/builtins/stdtypes.html#str), [`Any`](https://docs.python.org/3/library/typing.html#typing.Any)\] | [`None`](https://docs.python.org/3/builtins/constants.html#None) **Default:** `None`

### UserTurnStarted

**Bases:** `LifecycleEvent`

The user began a spoken turn (the provider heard speech start, or a commit names a turn it hadn't).

### UserTurnEnded

**Bases:** `LifecycleEvent`

A spoken turn joined the provider's conversation, at this point in its order.

#### Attributes

##### still\_speaking

Whether it joined while the user is still saying it (xAI adds its item at speech start): its audio, and with it the turn, then ends with the speech.

**Type:** [`bool`](https://docs.python.org/3/builtins/functions.html#bool) **Default:** `False`

##### before\_response

The response it joined ahead of, when the connection learned of the turn only after that response, its reply, had started (Gemini transcribes the user's words after the model starts answering them).

**Type:** [`str`](https://docs.python.org/3/builtins/stdtypes.html#str) | [`None`](https://docs.python.org/3/builtins/constants.html#None) **Default:** `None`

### UserTurnClosed

**Bases:** `LifecycleEvent`

No more audio or transcript is coming for a spoken turn.

It was cleared, its connection lost, or its transcript is over. One that hadn't joined the conversation (`UserTurnEnded`) is dropped, as it never will; one that had keeps what it has.

### InputAdded

**Bases:** `LifecycleEvent`

An input joined the provider's conversation, at this point in its order.

### InputLost

**Bases:** `LifecycleEvent`

The provider will never answer these inputs' request for a response.

The connection dropped the request (a barge-in cut off the response it was waiting behind), or lost it with the connection. The inputs' content, if any, is unaffected.

### ResponseRequestRefused

**Bases:** `LifecycleEvent`

The provider refused the request for a response made for these inputs, so none will answer them.

### ToolCallsAbandoned

**Bases:** `LifecycleEvent`

The provider gave up on these tool calls: no response will answer their results.

Eleven Realtime gives up on a finished response's calls once another response starts before their results are in, and GPT-Live on the calls its delegated backend asked for when that backend fails. The calls still run, and each result is recorded in history (and still sent, where the provider takes it), but nothing waits for a reply to it: the exchange is over once nothing else is owed. Unlike a [`ToolCallCancelled`](https://pydantic.dev/docs/ai/api/realtime/codec/#pydantic_ai.realtime.codec.ToolCallCancelled), it doesn't stop them.

#### Attributes

##### tool\_call\_ids

The calls, as their [`ToolCall`](https://pydantic.dev/docs/ai/api/realtime/codec/#pydantic_ai.realtime.codec.ToolCall)s named them.

**Type:** [`tuple`](https://docs.python.org/3/builtins/stdtypes.html#tuple)\[[`str`](https://docs.python.org/3/builtins/stdtypes.html#str), ...\]

### OutputItemDetails

**Bases:** `LifecycleEvent`

What the provider says about one item of a response's output, to keep on the part that item makes.

Like OpenAI's `phase`, which tells an assistant message the model meant as commentary on its way to a tool call apart from its final answer.

### OutputItemCut

**Bases:** `LifecycleEvent`

The provider says the listener heard only part of one spoken output item, before or after its response ended.

Generation outruns playback, so the reply the user cuts off has usually ended already. Its message in history is marked interrupted, and swapped for a copy in the same position, as one the session cuts off itself on a barge-in is: a snapshot of history already handed out doesn't change. Like ElevenLabs' `agent_response_correction`.

#### Attributes

##### item\_id

The output item, as the codec events streaming it named it (`OutputTranscript.item_id`).

**Type:** [`str`](https://docs.python.org/3/builtins/stdtypes.html#str)

##### heard\_transcript

What the listener heard of the item's transcript, which history then records instead, keeping the provider's original in the part's `provider_details['original_transcript']`: `''` for an item they heard none of. `None` leaves the transcript as it is.

**Type:** [`str`](https://docs.python.org/3/builtins/stdtypes.html#str) | [`None`](https://docs.python.org/3/builtins/constants.html#None) **Default:** `None`

##### heard\_ms

How much of the item's audio the listener heard, in milliseconds, if known.

**Type:** [`int`](https://docs.python.org/3/builtins/functions.html#int) | [`None`](https://docs.python.org/3/builtins/constants.html#None) **Default:** `None`

### StaleEvent

A codec event about a response that has already ended: a repeated terminal, or content trailing it.

The application still receives `event`, as it always has, but nothing applies it to the conversation: the response it is about is over. A connection that can't tell such events apart (most can't) never yields one.

### InputId

An input's position among every `send()` call made on a connection, as in `InputRejected.input_index`.

**Default:** `int`

### AnswersBasis

Where a response's `answers` come from: the provider's own word, or the connection's bookkeeping.

**Default:** `Literal['protocol', 'inferred']`

### ResponseStatus

How a response ended. `'lost'` is a response the connection gave up on: its connection dropped (and the reconnect did not carry it over) or closed before the provider reported it done.

**Default:** `Literal['completed', 'cancelled', 'failed', 'incomplete', 'lost']`

### RealtimeFrame

What one message from the provider (or one transition of the connection's own, like a reconnect) makes.

The events are in order, and the session applies a frame whole before it streams any of it, so whatever reacts to one of its events finds the conversation as far along as the frame takes it.

**Default:** `TypeAliasType('RealtimeFrame', 'list[RealtimeCodecEvent | LifecycleEvent | StaleEvent]')`