ContextCompressionCall

SUPPORT · interface · Type contract

One compression request.

Import

TypeScript

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

JavaScript

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

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

Definition

interface ContextCompressionCall

Field structure

Field	Type	Required	Description
stageId	string	Required	Read-only. See the type definition and usage context.
fragment	ContextFragment	Required	Fragment to compress; its targetChars bound is enforced by the engine.
targetChars	number	Required	See the type definition and usage context.
callModel	ContextModelCall	Required	Same runner's budget, timeout, transports and diagnostics. No recursive processing.

Member index

Member	Purpose
callModel	Same runner's budget, timeout, transports and diagnostics. No recursive processing.

Member details

callModel

Same runner's budget, timeout, transports and diagnostics. No recursive processing.

ContextCompressionCall.callModel(request: ContextModelRequest): Promise<ModelResult<unknown>>

Parameter	Type	Passing	Description
request	ContextModelRequest	Required	—

Fields of request

Field	Type	Required	Description
modelId	string | undefined	Optional	Read-only. See the type definition and usage context.
stageId	string	Required	Read-only. See the type definition and usage context.
input	readonly ModelMessage[] | BuiltContext	Required	Read-only. See the type definition and usage context.
maxOutputTokens	number	Required	Read-only. See the type definition and usage context.
transport	string	Required	Read-only. See the type definition and usage context.

Returns: Promise<ModelResult<unknown>>.

Awaited value: ModelResult<unknown>.

Return value structure

Field	Type	Required	Description
value	unknown	Required	Read-only. See the type definition and usage context.
invocation	Readonly<ModelCallRecord>	Required	Read-only. See the type definition and usage context.

Examples

• Compressors and selectors: recommended implementations and custom algorithms: Bind prompts, output parsing, and algorithms as handlers; model I/O goes through callModel of the same request.

Bind a text compression handler

Beginner · Node.js

TypeScript

import { Support } from '@jangts/agent-core';
const compressor = Support.createContextCompressor({
  id: 'history-summary', instruction: '保留事实、时间和未完成事项，精简重复表达。',
  transport: 'core:plain-text', maxOutputTokens: 500,
  parse(value: unknown) { if (typeof value !== 'string' || !value.trim()) throw new TypeError('需要非空摘要'); return value; },
});
console.log(compressor.id);

JavaScript

import { Support } from '@jangts/agent-core';
const compressor = Support.createContextCompressor({
    id: 'history-summary', instruction: '保留事实、时间和未完成事项，精简重复表达。',
    transport: 'core:plain-text', maxOutputTokens: 500,
    parse(value) { if (typeof value !== 'string' || !value.trim())
        throw new TypeError('需要非空摘要'); return value; },
});
console.log(compressor.id);

A selector explicitly controls the visible excerpt range

Configuration · Node.js

selector-json must be registered by the App and return value={stepIds:string[]}; an ordinary text transport must not be treated as already parsed JSON. This example only shows handler assembly and sends no request.

TypeScript

import { Support } from '@jangts/agent-core';
const selector = Support.createContextSelector({ id: 'select-reduction',
  transport: 'selector-json', maxOutputTokens: 200, maxExcerptChars: 1000,
});
console.log(selector.id);

JavaScript

import { Support } from '@jangts/agent-core';
const selector = Support.createContextSelector({ id: 'select-reduction',
    transport: 'selector-json', maxOutputTokens: 200, maxExcerptChars: 1000,
});
console.log(selector.id);

Related policy source

• Default selection instruction and excerpt range
• Compression request and the real callModel contract

Related definitions

• ContextFragment
• ContextModelCall
• ContextModelRequest
• ModelCallRecord
• ModelResult