ContextPlan

CORE · interface · Type contract

Unassembled input; App-side nodes may process it before the Core budget boundary.

Import

TypeScript

import type { ContextPlan } from '@jangts/agent-core/context';

JavaScript

/** @typedef {import('@jangts/agent-core/context').ContextPlan} ContextPlan */

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

Definition

interface ContextPlan

Field structure

Field	Type	Required	Description
fragments	readonly ContextFragment[]	Required	Read-only. Fragments in the order supplied by the App; assembly preserves it.
maxInputChars	number	Required	Character budget Core validates after assembly.
additionalMessages	readonly (ModelMessage & { role: "user"; })[] | undefined	Optional	Protected user messages (for example image inputs); text counts toward the same budget.
originalFragments	readonly ContextFragment[] | undefined	Optional	Trusted originals for structural mutation auditing; never sent to the model.
mutableFragmentIds	readonly string[] | undefined	Optional	Explicit value-mutation allowance when originals are supplied.

Examples

• Context fragments: explicit source, trust, and budget: Core recognizes fragments and the assembly contract, validates source metadata and budgets, and has no built-in business compression algorithm.

Assemble one input from bare configuration

Beginner · Node.js

TypeScript

import { assembleFragments } from '@jangts/agent-core/context';
const input = assembleFragments([{ id: 'question', sourceId: 'request', trust: 'user',
  lifetime: 'turn', maxChars: 1000, role: 'user', value: '现在服务状态怎样？' }], 2000);
console.log(input.messages, input.fragmentUsage);

JavaScript

import { assembleFragments } from '@jangts/agent-core/context';
const input = assembleFragments([{ id: 'question', sourceId: 'request', trust: 'user',
        lifetime: 'turn', maxChars: 1000, role: 'user', value: '现在服务状态怎样？' }], 2000);
console.log(input.messages, input.fragmentUsage);

Add a candidate plan and final audit

Configuration · Node.js

An empty mutable fragment list means the original fragments may not be modified; no compression step is authorized automatically.

TypeScript

import { assembleContextPlan } from '@jangts/agent-core/context';
import type { ContextFragment } from '@jangts/agent-core/types';
const fragments: ContextFragment[] = [{ id: 'question', sourceId: 'request', trust: 'user',
  lifetime: 'turn', maxChars: 1000, role: 'user', value: '现在服务状态怎样？' }];
const input = assembleContextPlan({ fragments, originalFragments: fragments, mutableFragmentIds: [], maxInputChars: 2000 });
console.log(input.inputChars);

JavaScript

import { assembleContextPlan } from '@jangts/agent-core/context';
const fragments = [{ id: 'question', sourceId: 'request', trust: 'user',
        lifetime: 'turn', maxChars: 1000, role: 'user', value: '现在服务状态怎样？' }];
const input = assembleContextPlan({ fragments, originalFragments: fragments, mutableFragmentIds: [], maxInputChars: 2000 });
console.log(input.inputChars);

Related policy source

• Fragment validation and budget rejection

Related definitions

• ContextFragment
• ModelMessage