ContextHistoryGrouping

SUPPORT · type · Type contract

How a message history is split into groups for trimming.

Import

TypeScript

import type { ContextHistoryGrouping } from '@jangts/agent-core/support';

JavaScript

/** @typedef {import('@jangts/agent-core/support').ContextHistoryGrouping} ContextHistoryGrouping */

Other public entry points:@jangts/agent-core/support, @jangts/agent-core/support/context.

Definition

Type: ContextHistoryGrouping

Union branch structure

Optional shapes of ContextHistoryGrouping: choose one shape; required fields for each branch are listed separately.

Branch 1

Field	Type	Required	Description
kind	"fixed"	Required	See the type definition and usage context.
size	number	Required	See the type definition and usage context.

Branch 2

Field	Type	Required	Description
kind	"user-turn"	Required	See the type definition and usage context.

Examples

• Context policy: validate, reduce, and audit: Support provides replaceable policy implementations while Core keeps the final input contract and budget checks.

Explicitly use a validation-only policy

Beginner · Node.js

TypeScript

import { Support } from '@jangts/agent-core';
import type { ContextPolicy } from '@jangts/agent-core/support/context';
const policy: ContextPolicy = { mode: 'validate' };
Support.validateContextPolicy(policy, [], []);
console.log(policy.mode);

JavaScript

import { Support } from '@jangts/agent-core';
const policy = { mode: 'validate' };
Support.validateContextPolicy(policy, [], []);
console.log(policy.mode);

Configure reduction order from real business fragments

Configuration · Node.js

These numbers are explicit choices for the example business, not SDK recommendations for capacities that suit all models.

TypeScript

import { Support } from '@jangts/agent-core';
import type { ContextPolicy } from '@jangts/agent-core/support/context';
const policy: ContextPolicy = { mode: 'reduce', triggerChars: 1800, targetInputChars: 1500,
  selection: { mode: 'sequence' },
  steps: [{ id: 'recent-history', kind: 'trim', fragmentId: 'history', field: 'messages',
    grouping: { kind: 'user-turn' }, keepGroups: 2, targetChars: 1000 }],
};
Support.validateContextPolicy(policy, [], []);
console.log(policy.steps);

JavaScript

import { Support } from '@jangts/agent-core';
const policy = { mode: 'reduce', triggerChars: 1800, targetInputChars: 1500,
    selection: { mode: 'sequence' },
    steps: [{ id: 'recent-history', kind: 'trim', fragmentId: 'history', field: 'messages',
            grouping: { kind: 'user-turn' }, keepGroups: 2, targetChars: 1000 }],
};
Support.validateContextPolicy(policy, [], []);
console.log(policy.steps);

Related policy source

• Real scheduling catalog for policies and reduction operations