> ## Documentation Index
> Fetch the complete documentation index at: https://qitor.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Context 与 memory 契约

> QitOS public API: context

通过显式扩展名注册 contributor、selector、budget policy 与 compactor。context 选择不授予工具权限。CompactionReceipt 声明输入、输出身份和损失，省略不是无损摘要。memory 输入不是 checkpoint store。缺失工厂在组合时失败；可执行教程展示方法参数及实际有损 compaction。

[完整可运行教程 / Complete tutorial](/zh/guides/memory-and-history) · [API index](/zh/reference/api)

以下签名和字段由固定源码提取；签名是参考，不是可直接运行的程序。每个条目的源码链接绑定同一 runtime baseline。类型中的 Any 不代表任意对象均受支持，应结合上述行为契约和教程使用。

具体 module API 为 `qitos.kit.memory.adapter.MemorySourceAdapter(memory, *, namespace, query=None, required=False, priority=0)` 和 `qitos.kit.context.compaction.ClosedExchangeWindowCompactor()`。通过现有 `extensions` mapping 绑定，不增加 root export 或 Engine 构造参数。Memdir 恢复时明确报告缺失资源（`create=True` 用于初始化）；Markdown 仅在当前实例内召回。required contribution 的优先级高于 optional contribution。

RequestView 的预算驱动 exchange 省略现在要求显式 compaction policy。`compact` callback 收到符合省略条件的 IDs 和已选择 exchange projection 的 SHA-256 digest，必须返回对应的损失 receipt。已有 receipt 本身不授权新的省略。request builder 负责最近窗口和全部保护检查，continuation 采用保守保护。Python-only context 预算/损失设置和迁移边界见教程。

<span id="qitos-core-context-staticcontextcontributor" />

## StaticContextContributor

```python theme={null}
from qitos.core.context import StaticContextContributor
```

[Source @ d000a42](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/core/context.py#L302)

[用法与可执行示例](/zh/guides/memory-and-history)

用法片段：接续上方完整教程中的对象，不是独立程序。

```python theme={null}
contributor = StaticContextContributor("notes.project", "project", "Use supplied notes only.")
```

```text theme={null}
Small reusable contributor for project/user/session context.
```

| Field                 | Type   | Default             |
| --------------------- | ------ | ------------------- |
| `contributor_id`      | `str`  | `required`          |
| `source`              | `str`  | `required`          |
| `value`               | `Any`  | `field(repr=False)` |
| `priority`            | `int`  | `0`                 |
| `requested_placement` | `str`  | `'developer'`       |
| `required`            | `bool` | `False`             |
| `persistence_horizon` | `str`  | `'request'`         |
| `sensitivity`         | `str`  | `'internal'`        |

<span id="qitos-core-context-prioritycontextselectionpolicy" />

## PriorityContextSelectionPolicy

```python theme={null}
from qitos.core.context import PriorityContextSelectionPolicy
```

[Source @ d000a42](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/core/context.py#L118)

[用法与可执行示例](/zh/guides/memory-and-history)

用法片段：接续上方完整教程中的对象，不是独立程序。

```python theme={null}
class AuditedSelector(PriorityContextSelectionPolicy):
    def select(self, contributions, **options):
        contributions = tuple(contributions)
        print([item.contribution_id for item in contributions])
        return super().select(contributions, **options)
```

```text theme={null}
Default deterministic priority/identity selection policy.
```

| Field       | Type  | Default                       |
| ----------- | ----- | ----------------------------- |
| `policy_id` | `str` | `'qitos.context.priority/v1'` |

<span id="qitos-core-context-prioritycontextselectionpolicy-select" />

### PriorityContextSelectionPolicy.select

```text theme={null}
select(contributions: Iterable[ContextContribution], *, budget: ContextBudget, already_used_units: int=0, counter: UnitCounter=default_unit_counter) -> ContextSelection
```

| Parameter            | Type                            | Default                |
| -------------------- | ------------------------------- | ---------------------- |
| `contributions`      | `Iterable[ContextContribution]` | `required`             |
| `budget`             | `ContextBudget`                 | `required`             |
| `already_used_units` | `int`                           | `0`                    |
| `counter`            | `UnitCounter`                   | `default_unit_counter` |

[Source](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/core/context.py#L123)

<span id="qitos-core-context-declaredcontextbudgetpolicy" />

## DeclaredContextBudgetPolicy

```python theme={null}
from qitos.core.context import DeclaredContextBudgetPolicy
```

[Source @ d000a42](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/core/context.py#L189)

[用法与可执行示例](/zh/guides/memory-and-history)

用法片段：接续上方完整教程中的对象，不是独立程序。

```python theme={null}
policy = DeclaredContextBudgetPolicy(default_max_input_units=4096)
```

```text theme={null}
Use adapter-declared capacity; never infer it from a model name.
```

| Field                        | Type  | Default                              |
| ---------------------------- | ----- | ------------------------------------ |
| `default_max_input_units`    | `int` | `120000`                             |
| `unit`                       | `str` | `'characters'`                       |
| `protected_recent_exchanges` | `int` | `1`                                  |
| `policy_id`                  | `str` | `'qitos.context.declared_budget/v1'` |

<span id="qitos-core-request_view-compactionreceipt" />

## CompactionReceipt

```python theme={null}
from qitos.core.request_view import CompactionReceipt
```

[Source @ d000a42](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/core/request_view.py#L530)

[用法与可执行示例](/zh/guides/memory-and-history)

用法片段：接续上方完整教程中的对象，不是独立程序。

```python theme={null}
# receipt is returned by the compactor in the context tutorial.
print(receipt.declared_losses, receipt.output_digest)
```

| Field                | Type              | Default    |
| -------------------- | ----------------- | ---------- |
| `receipt_id`         | `str`             | `required` |
| `input_exchange_ids` | `tuple[str, ...]` | `required` |
| `output_digest`      | `str`             | `required` |
| `policy_id`          | `str`             | `required` |
| `declared_losses`    | `tuple[str, ...]` | `()`       |
| `model_reference`    | `Optional[str]`   | `None`     |

<span id="qitos-core-memory-memoryrecord" />

## MemoryRecord

```python theme={null}
from qitos.core.memory import MemoryRecord
```

[Source @ d000a42](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/core/memory.py#L20)

[用法与可执行示例](/zh/guides/memory-and-history)

用法片段：接续上方完整教程中的对象，不是独立程序。

```python theme={null}
record = MemoryRecord("user", "remembered-value=17", 0)
```

```text theme={null}
One logical memory fact; independent equal facts receive distinct IDs.
```

| Field       | Type             | Default                                      |
| ----------- | ---------------- | -------------------------------------------- |
| `role`      | `str`            | `required`                                   |
| `content`   | `Any`            | `required`                                   |
| `step_id`   | `int`            | `required`                                   |
| `metadata`  | `Dict[str, Any]` | `field(default_factory=dict)`                |
| `record_id` | `str`            | `field(default_factory=lambda: uuid4().hex)` |

<span id="qitos-core-memory-memoryresourceerror" />

## MemoryResourceError

```python theme={null}
from qitos.core.memory import MemoryResourceError
```

[Source @ d000a42](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/core/memory.py#L13)

[用法与可执行示例](/zh/guides/memory-and-history)

用法片段：接续上方完整教程中的对象，不是独立程序。

```python theme={null}
# Restore raises MemoryResourceError if the bound root is missing.
```

```text theme={null}
A bound durable memory resource is missing or unavailable.
```

<span id="qitos-kit-memory-memdir_memory-memdirmemory" />

## MemdirMemory

```python theme={null}
from qitos.kit.memory.memdir_memory import MemdirMemory
```

[Source @ d000a42](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/kit/memory/memdir_memory.py#L16)

[用法与可执行示例](/zh/guides/memory-and-history)

用法片段：接续上方完整教程中的对象，不是独立程序。

```python theme={null}
memory = MemdirMemory("./project-memory", create=True)
memory.append(MemoryRecord("user", "remembered-value=17", 0))
# Later process: MemdirMemory("./project-memory")
```

```text theme={null}
Persist text records with stable identity and fresh disk retrieval.

Restore is the default and fails if a bound root is missing. Pass
``create=True`` only to explicitly initialize a namespace. ``reset`` and
``evict`` affect the append-time cache only; ``delete`` removes a local fact.
Arbitrary Python/JSON content and metadata are not a durable round-trip API.
```

```text theme={null}
MemdirMemory(memory_dir: str='.qitos/memory', *, global_memory_dir: str | None=None, create: bool=False, max_index_entries: int=200, max_index_chars: int=25000) -> Any (see behavior contract)
```

| Parameter           | Type          | Default           |
| ------------------- | ------------- | ----------------- |
| `memory_dir`        | `str`         | `'.qitos/memory'` |
| `global_memory_dir` | `str \| None` | `None`            |
| `create`            | `bool`        | `False`           |
| `max_index_entries` | `int`         | `200`             |
| `max_index_chars`   | `int`         | `25000`           |

<span id="qitos-kit-memory-memdir_memory-memdirmemory-append" />

### MemdirMemory.append

```text theme={null}
append(record: MemoryRecord) -> None
```

| Parameter | Type           | Default    |
| --------- | -------------- | ---------- |
| `record`  | `MemoryRecord` | `required` |

[Source](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/kit/memory/memdir_memory.py#L47)

<span id="qitos-kit-memory-memdir_memory-memdirmemory-retrieve" />

### MemdirMemory.retrieve

```text theme={null}
retrieve(query: Optional[Dict[str, Any]]=None, state: Any=None, observation: Any=None) -> List[MemoryRecord]
```

| Parameter     | Type                       | Default |
| ------------- | -------------------------- | ------- |
| `query`       | `Optional[Dict[str, Any]]` | `None`  |
| `state`       | `Any`                      | `None`  |
| `observation` | `Any`                      | `None`  |

[Source](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/kit/memory/memdir_memory.py#L103)

<span id="qitos-kit-memory-memdir_memory-memdirmemory-summarize" />

### MemdirMemory.summarize

```text theme={null}
summarize(max_items: int=30) -> str
```

| Parameter   | Type  | Default |
| ----------- | ----- | ------- |
| `max_items` | `int` | `30`    |

```text theme={null}
Render current records, never stale index snippets after external edits.
```

[Source](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/kit/memory/memdir_memory.py#L142)

<span id="qitos-kit-memory-memdir_memory-memdirmemory-reset" />

### MemdirMemory.reset

```text theme={null}
reset(run_id: Optional[str]=None) -> None
```

| Parameter | Type            | Default |
| --------- | --------------- | ------- |
| `run_id`  | `Optional[str]` | `None`  |

[Source](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/kit/memory/memdir_memory.py#L157)

<span id="qitos-kit-memory-memdir_memory-memdirmemory-evict" />

### MemdirMemory.evict

```text theme={null}
evict() -> int
```

[Source](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/kit/memory/memdir_memory.py#L150)

<span id="qitos-kit-memory-memdir_memory-memdirmemory-delete" />

### MemdirMemory.delete

```text theme={null}
delete(record_id: str) -> bool
```

| Parameter   | Type  | Default    |
| ----------- | ----- | ---------- |
| `record_id` | `str` | `required` |

```text theme={null}
Forget one logical record in this namespace, never global memory.

Idempotent for an absent identity. This is local-file deletion, not
secure erasure or a concurrent multi-file transaction. Callers serialize
writes to one Memdir namespace; use a transactional backend otherwise.
```

[Source](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/kit/memory/memdir_memory.py#L78)

<span id="qitos-kit-memory-markdown_file_memory-markdownfilememory" />

## MarkdownFileMemory

```python theme={null}
from qitos.kit.memory.markdown_file_memory import MarkdownFileMemory
```

[Source @ d000a42](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/kit/memory/markdown_file_memory.py#L12)

[用法与可执行示例](/zh/guides/memory-and-history)

用法片段：接续上方完整教程中的对象，不是独立程序。

```python theme={null}
memory = MarkdownFileMemory("./run-memory.md")
# Existing logs are not reloaded; recall is instance-scoped.
```

```text theme={null}
Persist memory records in a local markdown log file.
```

```text theme={null}
MarkdownFileMemory(path: str='memory.md', max_in_memory: int=200) -> Any (see behavior contract)
```

| Parameter       | Type  | Default       |
| --------------- | ----- | ------------- |
| `path`          | `str` | `'memory.md'` |
| `max_in_memory` | `int` | `200`         |

<span id="qitos-kit-memory-adapter-memorysourceadapter" />

## MemorySourceAdapter

```python theme={null}
from qitos.kit.memory.adapter import MemorySourceAdapter
```

[Source @ d000a42](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/kit/memory/adapter.py#L15)

[用法与可执行示例](/zh/guides/memory-and-history)

用法片段：接续上方完整教程中的对象，不是独立程序。

```python theme={null}
source = MemorySourceAdapter(memory, namespace="project", required=True)
# Bind source as extensions["project_memory"].
```

```text theme={null}
Recall a factory-bound namespace as user-level context data.

Namespace is a logical label, not a directory selector or an authorization.
The factory must bind the correct Memory resource. No global memory is read
by this adapter. Every request recalls fresh data, including after restore;
revision is provenance, never a permanent suppression cache.
```

```text theme={null}
MemorySourceAdapter(memory: Memory, *, namespace: str, query: Mapping[str, Any] | None=None, required: bool=False, priority: int=0) -> None
```

| Parameter   | Type                        | Default    |
| ----------- | --------------------------- | ---------- |
| `memory`    | `Memory`                    | `required` |
| `namespace` | `str`                       | `required` |
| `query`     | `Mapping[str, Any] \| None` | `None`     |
| `required`  | `bool`                      | `False`    |
| `priority`  | `int`                       | `0`        |

<span id="qitos-kit-memory-adapter-memorysourceadapter-contribute" />

### MemorySourceAdapter.contribute

```text theme={null}
contribute(request: Any) -> Sequence[ContextContribution]
```

| Parameter | Type  | Default    |
| --------- | ----- | ---------- |
| `request` | `Any` | `required` |

[Source](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/kit/memory/adapter.py#L48)

<span id="qitos-kit-memory-adapter-memorysourceadapter-reset" />

### MemorySourceAdapter.reset

```text theme={null}
reset(run_id: str | None=None) -> None
```

| Parameter | Type          | Default |
| --------- | ------------- | ------- |
| `run_id`  | `str \| None` | `None`  |

```text theme={null}
No owned state; never reset the borrowed memory.
```

[Source](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/kit/memory/adapter.py#L79)

<span id="qitos-kit-memory-adapter-memorysourceadapter-close" />

### MemorySourceAdapter.close

```text theme={null}
close() -> None
```

```text theme={null}
No owned resources; never close the borrowed memory.
```

[Source](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/kit/memory/adapter.py#L82)

<span id="qitos-kit-context-compaction-closedexchangewindowcompactor" />

## ClosedExchangeWindowCompactor

```python theme={null}
from qitos.kit.context.compaction import ClosedExchangeWindowCompactor
```

[Source @ d000a42](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/kit/context/compaction.py#L12)

[用法与可执行示例](/zh/guides/memory-and-history)

用法片段：接续上方完整教程中的对象，不是独立程序。

```python theme={null}
extensions["closed_window"] = ClosedExchangeWindowCompactor
# Configure compaction={"provider": "closed_window"}; the policy supplies receipts.
```

```text theme={null}
Omit the oldest eligible closed exchanges without a summary.

RequestView owns eligibility and the ContextBudget recent-window boundary.
This stateless policy authorizes that derived selection and records its loss;
it never modifies an ExchangeLog or widens a budget or codec loss setting.
```

<span id="qitos-kit-context-compaction-closedexchangewindowcompactor-compact" />

### ClosedExchangeWindowCompactor.compact

```text theme={null}
compact(*, exchange_ids: Sequence[str], selected_digest: str, required_units: int, available_units: int) -> CompactionReceipt | None
```

| Parameter         | Type            | Default    |
| ----------------- | --------------- | ---------- |
| `exchange_ids`    | `Sequence[str]` | `required` |
| `selected_digest` | `str`           | `required` |
| `required_units`  | `int`           | `required` |
| `available_units` | `int`           | `required` |

[Source](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/kit/context/compaction.py#L22)

<span id="qitos-core-request_view-requestview" />

## RequestView

```python theme={null}
from qitos.core.request_view import RequestView
```

[Source @ d000a42](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/core/request_view.py#L794)

[用法与可执行示例](/zh/guides/memory-and-history)

用法片段：接续上方完整教程中的对象，不是独立程序。

```python theme={null}
# Advanced direct projection; normal users select the configured compactor.
view = RequestView.from_exchange_log(log, compaction_policy=ClosedExchangeWindowCompactor())
```

```text theme={null}
One immutable, deterministic provider-neutral model request view.
```

| Field                     | Type                            | Default                                                                                                 |
| ------------------------- | ------------------------------- | ------------------------------------------------------------------------------------------------------- |
| `request_id`              | `str`                           | `required`                                                                                              |
| `target`                  | `RequestTarget`                 | `required`                                                                                              |
| `source_log_id`           | `str`                           | `required`                                                                                              |
| `source_log_digest`       | `str`                           | `required`                                                                                              |
| `selected_items_json`     | `tuple[str, ...]`               | `field(repr=False)`                                                                                     |
| `instructions_json`       | `tuple[str, ...]`               | `field(default=(), repr=False)`                                                                         |
| `tool_schemas_json`       | `tuple[str, ...]`               | `field(default=(), repr=False)`                                                                         |
| `context_json`            | `tuple[str, ...]`               | `field(default=(), repr=False)`                                                                         |
| `capability_requirements` | `tuple[str, ...]`               | `()`                                                                                                    |
| `reasoning_policy`        | `ReasoningPolicy`               | `field(default_factory=ReasoningPolicy)`                                                                |
| `continuation`            | `Optional[ContinuationRef]`     | `None`                                                                                                  |
| `context_budget`          | `ContextBudget`                 | `field(default_factory=ContextBudget)`                                                                  |
| `selection`               | `SelectionReport`               | `field(default_factory=lambda: SelectionReport((), (), (), (), (), (), (), (), 0, 0, 0, 'characters'))` |
| `compaction_receipts`     | `tuple[CompactionReceipt, ...]` | `()`                                                                                                    |
| `artifact_refs`           | `tuple[ArtifactRef, ...]`       | `()`                                                                                                    |
| `steering_boundary_json`  | `str`                           | `'{}'`                                                                                                  |
| `correlation_facts_json`  | `tuple[str, ...]`               | `field(default=(), repr=False)`                                                                         |
| `provenance_json`         | `str`                           | `'{}'`                                                                                                  |
| `protocol_id`             | `str`                           | `'unknown'`                                                                                             |
| `tool_use_policy`         | `str`                           | `'auto'`                                                                                                |
| `tool_use_satisfied`      | `bool`                          | `False`                                                                                                 |
| `schema_version`          | `str`                           | `REQUEST_VIEW_SCHEMA_VERSION`                                                                           |

<span id="qitos-core-request_view-requestview-from-exchange-log" />

### RequestView\.from\_exchange\_log

```text theme={null}
from_exchange_log(log: ExchangeLog, *, model: Any=None, target: Optional[RequestTarget]=None, instructions: Iterable[Mapping[str, Any]]=(), tool_schemas: Iterable[Mapping[str, Any]]=(), capability_requirements: Iterable[str]=(), reasoning_policy: Optional[ReasoningPolicy]=None, continuation: Optional[ContinuationRef]=None, context_budget: Optional[ContextBudget]=None, context_contributions: Iterable[ContextContribution]=(), context_selection_policy: Any=None, context_unit_counter: Any=None, compaction_receipts: Iterable[CompactionReceipt]=(), compaction_policy: Any=None, artifact_refs: Iterable[ArtifactRef]=(), available_artifact_ids: Optional[Iterable[str]]=None, protocol_id: str='unknown', tool_use_policy: str='auto', tool_use_satisfied: bool=False) -> 'RequestView'
```

| Parameter                  | Type                            | Default     |
| -------------------------- | ------------------------------- | ----------- |
| `log`                      | `ExchangeLog`                   | `required`  |
| `model`                    | `Any`                           | `None`      |
| `target`                   | `Optional[RequestTarget]`       | `None`      |
| `instructions`             | `Iterable[Mapping[str, Any]]`   | `()`        |
| `tool_schemas`             | `Iterable[Mapping[str, Any]]`   | `()`        |
| `capability_requirements`  | `Iterable[str]`                 | `()`        |
| `reasoning_policy`         | `Optional[ReasoningPolicy]`     | `None`      |
| `continuation`             | `Optional[ContinuationRef]`     | `None`      |
| `context_budget`           | `Optional[ContextBudget]`       | `None`      |
| `context_contributions`    | `Iterable[ContextContribution]` | `()`        |
| `context_selection_policy` | `Any`                           | `None`      |
| `context_unit_counter`     | `Any`                           | `None`      |
| `compaction_receipts`      | `Iterable[CompactionReceipt]`   | `()`        |
| `compaction_policy`        | `Any`                           | `None`      |
| `artifact_refs`            | `Iterable[ArtifactRef]`         | `()`        |
| `available_artifact_ids`   | `Optional[Iterable[str]]`       | `None`      |
| `protocol_id`              | `str`                           | `'unknown'` |
| `tool_use_policy`          | `str`                           | `'auto'`    |
| `tool_use_satisfied`       | `bool`                          | `False`     |

[Source](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/core/request_view.py#L1017)

<span id="qitos-core-request_view-contextbudgetexceedederror" />

## ContextBudgetExceededError

```python theme={null}
from qitos.core.request_view import ContextBudgetExceededError
```

[Source @ d000a42](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/core/request_view.py#L60)

[用法与可执行示例](/zh/guides/memory-and-history)

用法片段：接续上方完整教程中的对象，不是独立程序。

```python theme={null}
# Required/protected exchanges cannot be removed to make a request fit.
```

<span id="qitos-engine-runtime-lifecyclepolicy" />

## LifecyclePolicy

```python theme={null}
from qitos.engine.runtime import LifecyclePolicy
```

[Source @ d000a42](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/engine/runtime.py#L88)

[用法与可执行示例](/zh/guides/memory-and-history)

用法片段：接续上方完整教程中的对象，不是独立程序。

```python theme={null}
class PauseFirstTool(LifecyclePolicy):
    policy_id = "notes.pause"
    def should_pause(self, context):
        return context.step_id == 0
```

```text theme={null}
Replaceable cooperative lifecycle policy; never a worker scheduler.
```

<span id="qitos-engine-runtime-lifecyclepolicy-should-pause" />

### LifecyclePolicy.should\_pause

```text theme={null}
should_pause(context: RuntimeSnapshotContext) -> bool
```

| Parameter | Type                     | Default    |
| --------- | ------------------------ | ---------- |
| `context` | `RuntimeSnapshotContext` | `required` |

[Source](https://github.com/WhitzardAgent/WhitzardOS/blob/d000a42aff30b87c812850ac1019ca197f420c09/qitos/engine/runtime.py#L94)