DefaultScheduler

DefaultScheduler 是异步工厂，返回一个可直接使用的调度器实例。它把模型（默认 FSRS-7）与 dateChrono 以及标准调度策略组合在一起，因此你只需配置它的选项。内部它与自定义 defineScheduler 使用同一套「定义与实例」机制——预设只是把各部分装配起来的便捷方式。

选项

从 FSRS-3~6 升级到 FSRS-7 时，省略 weights 以使用 FSRS-7 默认权重，或提供为 FSRS-7 训练的权重。重放历史用于重建卡片状态，不会转换旧版权重。

FSRS-7 卡片除 stability 和 difficulty 外还包含 stabilityFast。旧版 FSRS-3~6 的记忆状态需要通过 Reschedule 重放复习历史来重建；参数迁移不会迁移卡片状态，不应以 0.8 * stability 推测演化后的快速轨迹。预设为 FSRS-7 启用小数天数；enableShortTerm: false 仅关闭显式学习步骤，不会关闭模型的快速轨迹。

需要成本自适应保留率时，自行组合定义，用 schedulerCostAdrMiddleware 替换 schedulerDesiredRetentionMiddleware。Cost ADR 不是 DefaultScheduler 选项。

scheduler.nextInterval(memoryState, desiredRetention, { card, grade, elapsedDays }) 查询已计算的评分后状态所对应的间隔，只执行 handlers.nextInterval，不推进卡片或 chrono；共享间隔策略应放在这个钩子中。

选项	默认	用途
`version`	`'FSRS-7'`	选择 FSRS 模型：`'FSRS-3'`、`'FSRS-4'`、`'FSRS-4.5'`、`'FSRS-5'`, `'FSRS-6'` 或 `'FSRS-7'`。FSRS-7 无法迁移旧版 FSRS-3~6 的权重。
`weights`	预设权重	可选的训练权重；省略时使用所选版本的预设默认值。FSRS-7 需要恰好 34 个 FSRS-7 权重；传入旧版权重会在构造调度器时抛出异常。
`desiredRetention`	`0.9`	在计算间隔前应用的目标保留率。
`enableShortTerm`	`true`	启用学习与再学习步骤。
`learningSteps`	`['1m', '10m']`	`enableShortTerm` 开启时应用的学习步骤。
`relearningSteps`	`['10m']`	`enableShortTerm` 开启时应用的再学习步骤。
`graduatingInterval`	`1`	卡片处于 `Review` 时的最短间隔（天）。最终间隔更短时，卡片保持 `Learning`/`Relearning`。配置了步骤时，走完步骤以及 `Review` 卡片按 Hard、Good、Easy 都至少使用这个间隔。
`allowModelOverride`	FSRS-7: `true`; 其他版本: `false`	模型间隔比当前步骤长时，改用模型间隔。Again 不超过 `graduatingInterval`；Hard、Good 的间隔达到 `graduatingInterval` 时提前毕业。
`enableFuzz`	`false`	开启时分散间隔以增加变化。
`maximumInterval`	`36500`	间隔的天数上限。
`clearStatsOnForget`	`true`	`forget` 是否清空 `reps` 与 `lapses`。

DefaultScheduler 始终使用 dateChrono，并按中间件页面所述的顺序组合标准策略：目标保留率、模糊间隔、统计、scheduled days、学习步骤、最大间隔、单调间隔。选择 version 只改变模型及其参数，不改变这套策略。

import { function DefaultScheduler<Version extends DefaultSchedulerVersion = "FSRS-7">(options?: DefaultSchedulerOptions<Version>): Promise<DefaultScheduler<Version>>
type DefaultScheduler<Version extends DefaultSchedulerVersion = "FSRS-7"> = (Version extends "FSRS-7" ? Omit<SchedulerCore<SchedulerCoreEnv<SchedulerEnvFor<FSRS7DefaultSchedulerModel, Chrono<{
    readonly time: SRSSchema<{
        input: Date;
        output: Date;
    }>;
    readonly config: SRSSchema<{
        input: {
            readonly fractionalDays?: boolean | undefined;
        };
        output: {
            readonly fractionalDays: boolean;
        };
    }>;
    readonly fields: {
        readonly card: SRSSchema<{
            input: {
                dueAt: Date;
                lastReviewAt?: (Date | null) | undefined;
            };
            output: {
                dueAt: Date;
                lastReviewAt: Date | null;
            };
        }>;
        readonly revlog: SRSSchema<{
            input: {
                dueAt: Date;
                lastReviewAt?: (Date | null) | undefined;
                reviewTime: Date;
            };
            output: {
                dueAt: Date;
                lastReviewAt: Date | null;
                reviewTime: Date;
            };
        }>;
    };
}>, readonly [...]>>, ModelCore<...>, ChronoCore<...>>, "definition"> : Omit<...> & {
    ...;
}) & {
    ...;
}
DefaultScheduler, type Rating = 0 | 1 | 2 | 3 | 4
const Rating: Readonly<{
    readonly Manual: 0;
    readonly Again: 1;
    readonly Hard: 2;
    readonly Good: 3;
    readonly Easy: 4;
}>
Rating } from 'ts-fsrs'

const now = new Date('2026-01-01T00:00:00.000Z')
const const scheduler: DefaultScheduler<"FSRS-7">scheduler = await DefaultScheduler<"FSRS-7">(options?: DefaultSchedulerOptions<"FSRS-7"> | undefined): Promise<DefaultScheduler<"FSRS-7">>DefaultScheduler({
  DefaultSchedulerOptions<"FSRS-7">.version?: "FSRS-7" | undefinedFSRS model and parameter migration version; defaults to FSRS-7.version: 'FSRS-7',
  DefaultSchedulerOptions<Version extends DefaultSchedulerVersion = DefaultSchedulerVersion>.desiredRetention?: number | undefineddesiredRetention: 0.9,
  DefaultSchedulerOptions<Version extends DefaultSchedulerVersion = DefaultSchedulerVersion>.enableShortTerm?: boolean | undefinedEnable explicit learning steps. FSRS-7 always retains its intrinsic fast trace.enableShortTerm: true,
  DefaultSchedulerOptions<"FSRS-7">.learningSteps?: readonly (`${number}d` | `${number}m` | `${number}h`)[] | undefinedDefaults to ['1m', '10m'].learningSteps: ['1m', '10m'],
  DefaultSchedulerOptions<"FSRS-7">.relearningSteps?: readonly (`${number}d` | `${number}m` | `${number}h`)[] | undefinedDefaults to ['10m'].relearningSteps: ['10m'],
  DefaultSchedulerOptions<Version extends DefaultSchedulerVersion = DefaultSchedulerVersion>.enableFuzz?: boolean | undefinedenableFuzz: false,
  DefaultSchedulerOptions<Version extends DefaultSchedulerVersion = DefaultSchedulerVersion>.maximumInterval?: number | undefinedmaximumInterval: 36_500,
})
const const card: {
    cardId: string | number;
    stabilityFast: number;
    stability: number;
    difficulty: number;
    dueAt: Date;
    lastReviewAt: Date | null;
    reps: number;
    lapses: number;
    scheduledDays: number;
    learningStep: number;
    state: State;
    scheduleStatus: "review" | "new" | "learning";
}
card = const scheduler: DefaultScheduler<"FSRS-7">scheduler.newCard: (options?: ({
    readonly cardId?: string | number | undefined;
} & {
    readonly now?: Date | undefined;
}) | undefined) => {
    cardId: string | number;
    stabilityFast: number;
    stability: number;
    difficulty: number;
    dueAt: Date;
    lastReviewAt: Date | null;
    reps: number;
    lapses: number;
    scheduledDays: number;
    learningStep: number;
    state: State;
    scheduleStatus: "review" | "new" | "learning";
}
newCard({ cardId: 'quick-start', now })
const const result: {
    card: {
        cardId: string | number;
        stabilityFast: number;
        stability: number;
        difficulty: number;
        dueAt: Date;
        lastReviewAt: Date | null;
        reps: number;
        lapses: number;
        scheduledDays: number;
        learningStep: number;
        state: State;
        scheduleStatus: "review" | "new" | "learning";
    };
    revlog: {
        cardId: string | number;
        stabilityFast: number;
        stability: number;
        difficulty: number;
        dueAt: Date;
        lastReviewAt: Date | null;
        scheduledDays: number;
        learningStep: number;
        reviewTime: Date;
        state: State;
        scheduleStatus: "review" | "new" | "learning";
        rating: Grade;
    };
}
result = const scheduler: DefaultScheduler<"FSRS-7">scheduler.review: (input: {
    readonly card: Readonly<Omit<Readonly<{
        stabilityFast: number;
        stability: number;
        difficulty: number;
    } & {
        dueAt: Date;
        lastReviewAt: Date | null;
    } & {
        readonly cardId: string | number;
        readonly reps: number;
        readonly lapses: number;
        readonly scheduledDays: number;
        readonly learningStep?: number | undefined;
    } & SchedulerCoreFields$1<"review" | "new" | "learning">>, keyof SchedulerCoreFields$1<"review" | "new" | "learning">> & SchedulerCoreFields$1<"review" | "new" | "learning">>;
    readonly grade: Grade;
    readonly now?: Date | undefined;
}) => {
    ...;
}
review({ card, grade: const Rating: Readonly<{
    readonly Manual: 0;
    readonly Again: 1;
    readonly Hard: 2;
    readonly Good: 3;
    readonly Easy: 4;
}>
Rating.Good, now })

console.log(
  JSON.stringify(
    {
      state: const result: {
    card: {
        cardId: string | number;
        stabilityFast: number;
        stability: number;
        difficulty: number;
        dueAt: Date;
        lastReviewAt: Date | null;
        reps: number;
        lapses: number;
        scheduledDays: number;
        learningStep: number;
        state: State;
        scheduleStatus: "review" | "new" | "learning";
    };
    revlog: {
        cardId: string | number;
        stabilityFast: number;
        stability: number;
        difficulty: number;
        dueAt: Date;
        lastReviewAt: Date | null;
        scheduledDays: number;
        learningStep: number;
        reviewTime: Date;
        state: State;
        scheduleStatus: "review" | "new" | "learning";
        rating: Grade;
    };
}
result.card: {
    cardId: string | number;
    stabilityFast: number;
    stability: number;
    difficulty: number;
    dueAt: Date;
    lastReviewAt: Date | null;
    reps: number;
    lapses: number;
    scheduledDays: number;
    learningStep: number;
    state: State;
    scheduleStatus: "review" | "new" | "learning";
}
card.state,
      dueAt: const result: {
    card: {
        cardId: string | number;
        stabilityFast: number;
        stability: number;
        difficulty: number;
        dueAt: Date;
        lastReviewAt: Date | null;
        reps: number;
        lapses: number;
        scheduledDays: number;
        learningStep: number;
        state: State;
        scheduleStatus: "review" | "new" | "learning";
    };
    revlog: {
        cardId: string | number;
        stabilityFast: number;
        stability: number;
        difficulty: number;
        dueAt: Date;
        lastReviewAt: Date | null;
        scheduledDays: number;
        learningStep: number;
        reviewTime: Date;
        state: State;
        scheduleStatus: "review" | "new" | "learning";
        rating: Grade;
    };
}
result.card: {
    cardId: string | number;
    stabilityFast: number;
    stability: number;
    difficulty: number;
    dueAt: Date;
    lastReviewAt: Date | null;
    reps: number;
    lapses: number;
    scheduledDays: number;
    learningStep: number;
    state: State;
    scheduleStatus: "review" | "new" | "learning";
}
card.dueAt,
      stability: const result: {
    card: {
        cardId: string | number;
        stabilityFast: number;
        stability: number;
        difficulty: number;
        dueAt: Date;
        lastReviewAt: Date | null;
        reps: number;
        lapses: number;
        scheduledDays: number;
        learningStep: number;
        state: State;
        scheduleStatus: "review" | "new" | "learning";
    };
    revlog: {
        cardId: string | number;
        stabilityFast: number;
        stability: number;
        difficulty: number;
        dueAt: Date;
        lastReviewAt: Date | null;
        scheduledDays: number;
        learningStep: number;
        reviewTime: Date;
        state: State;
        scheduleStatus: "review" | "new" | "learning";
        rating: Grade;
    };
}
result.card: {
    cardId: string | number;
    stabilityFast: number;
    stability: number;
    difficulty: number;
    dueAt: Date;
    lastReviewAt: Date | null;
    reps: number;
    lapses: number;
    scheduledDays: number;
    learningStep: number;
    state: State;
    scheduleStatus: "review" | "new" | "learning";
}
card.stability,
      stabilityFast: const result: {
    card: {
        cardId: string | number;
        stabilityFast: number;
        stability: number;
        difficulty: number;
        dueAt: Date;
        lastReviewAt: Date | null;
        reps: number;
        lapses: number;
        scheduledDays: number;
        learningStep: number;
        state: State;
        scheduleStatus: "review" | "new" | "learning";
    };
    revlog: {
        cardId: string | number;
        stabilityFast: number;
        stability: number;
        difficulty: number;
        dueAt: Date;
        lastReviewAt: Date | null;
        scheduledDays: number;
        learningStep: number;
        reviewTime: Date;
        state: State;
        scheduleStatus: "review" | "new" | "learning";
        rating: Grade;
    };
}
result.card: {
    cardId: string | number;
    stabilityFast: number;
    stability: number;
    difficulty: number;
    dueAt: Date;
    lastReviewAt: Date | null;
    reps: number;
    lapses: number;
    scheduledDays: number;
    learningStep: number;
    state: State;
    scheduleStatus: "review" | "new" | "learning";
}
card.stabilityFast,
      difficulty: const result: {
    card: {
        cardId: string | number;
        stabilityFast: number;
        stability: number;
        difficulty: number;
        dueAt: Date;
        lastReviewAt: Date | null;
        reps: number;
        lapses: number;
        scheduledDays: number;
        learningStep: number;
        state: State;
        scheduleStatus: "review" | "new" | "learning";
    };
    revlog: {
        cardId: string | number;
        stabilityFast: number;
        stability: number;
        difficulty: number;
        dueAt: Date;
        lastReviewAt: Date | null;
        scheduledDays: number;
        learningStep: number;
        reviewTime: Date;
        state: State;
        scheduleStatus: "review" | "new" | "learning";
        rating: Grade;
    };
}
result.card: {
    cardId: string | number;
    stabilityFast: number;
    stability: number;
    difficulty: number;
    dueAt: Date;
    lastReviewAt: Date | null;
    reps: number;
    lapses: number;
    scheduledDays: number;
    learningStep: number;
    state: State;
    scheduleStatus: "review" | "new" | "learning";
}
card.difficulty,
      rating: const result: {
    card: {
        cardId: string | number;
        stabilityFast: number;
        stability: number;
        difficulty: number;
        dueAt: Date;
        lastReviewAt: Date | null;
        reps: number;
        lapses: number;
        scheduledDays: number;
        learningStep: number;
        state: State;
        scheduleStatus: "review" | "new" | "learning";
    };
    revlog: {
        cardId: string | number;
        stabilityFast: number;
        stability: number;
        difficulty: number;
        dueAt: Date;
        lastReviewAt: Date | null;
        scheduledDays: number;
        learningStep: number;
        reviewTime: Date;
        state: State;
        scheduleStatus: "review" | "new" | "learning";
        rating: Grade;
    };
}
result.revlog: {
    cardId: string | number;
    stabilityFast: number;
    stability: number;
    difficulty: number;
    dueAt: Date;
    lastReviewAt: Date | null;
    scheduledDays: number;
    learningStep: number;
    reviewTime: Date;
    state: State;
    scheduleStatus: "review" | "new" | "learning";
    rating: Grade;
}
revlog.rating,
    },
    null,
    2
  )
)

该工厂是异步的，使用返回的实例前要先 await DefaultScheduler(...)。示例把常用默认值写得很明确：version、desiredRetention、学习与再学习步骤、模糊间隔和 maximumInterval。省略 weights 即用所选 FSRS 版本的预设。

预设还是自定义定义

当默认的 FSRS 模型、dateChrono 与标准策略集契合你的产品时，用 DefaultScheduler——这是最快且正确的起点。当需要不同的模型或 chrono、增减策略，或需要为每个用户校验配置时，用 defineScheduler。二者最终都落到同一套调度器实例 API（newCard、review、rollback、preview 与 forget）。定义与实例模型见调度器概览。

#DefaultScheduler

#选项

#预设还是自定义定义

DefaultScheduler

选项

预设还是自定义定义