CompletionSession

SUPPORT · interface · Type contract

Per-request completion state observed by one policy.

Import

TypeScript

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

JavaScript

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

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

Definition

interface CompletionSession

Field structure

Field	Type	Required	Description
part	(part: ModelPart) => void	Required	Observe one part immediately before the provider yields it.
finish	(reason: string) => void	Required	Observe the stream's single finish_reason.
end	() => void	Required	Complete the response when the end-of-stream marker arrives.

Member index

Member	Purpose
part	Observe one part immediately before the provider yields it.
finish	Observe the stream's single finish_reason.
end	Complete the response when the end-of-stream marker arrives.

Member details

part

Observe one part immediately before the provider yields it.

CompletionSession.part(part: ModelPart): void

Observe one part immediately before the provider yields it.

Parameter	Type	Passing	Description
part	ModelPart	Required	—

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

Branch 1

string

Branch 2

Field	Type	Required	Description
type	"function-call-delta"	Required	See the type definition and usage context.
index	number	Required	Index of the call within the response; deltas with the same index belong together.
id	string | undefined	Optional	Provider call id, usually delivered once with the first delta.
name	string | undefined	Optional	Function name, usually delivered once with the first delta.
arguments	string | undefined	Optional	Raw JSON argument fragment; concatenating all fragments yields the full arguments.

Returns: void.

finish

Observe the stream's single finish_reason.

CompletionSession.finish(reason: string): void

Observe the stream's single finish_reason.

Parameter	Type	Passing	Description
reason	string	Required	—

Returns: void.

end

Complete the response when the end-of-stream marker arrives.

CompletionSession.end(): void

Complete the response when the end-of-stream marker arrives.

No call parameters.

Returns: void.

Examples

• Compatible Provider and custom Providers: Support owns the common Chat Completions HTTP/SSE lifecycle; an App can substitute its own ChatProvider.

Connect a common protocol with real server-side configuration

Beginner · Node.js

Running this example requires connection configuration for an available model service.

TypeScript

import { ModelRunner, Support } from '@jangts/agent-core';
const provider = new Support.CompatibleModelProvider({ config: {
  baseUrl: process.env.MODEL_BASE_URL!, apiKey: process.env.MODEL_API_KEY!, model: process.env.MODEL_NAME!,
} });
const runner = new ModelRunner({ provider });
console.log((await runner.invoke('你好')).value);

JavaScript

import { ModelRunner, Support } from '@jangts/agent-core';
const provider = new Support.CompatibleModelProvider({ config: {
        baseUrl: process.env.MODEL_BASE_URL, apiKey: process.env.MODEL_API_KEY, model: process.env.MODEL_NAME,
    } });
const runner = new ModelRunner({ provider });
console.log((await runner.invoke('你好')).value);

Declared fields and wire mapping for a direct tool thread

Configuration · Node.js

This only demonstrates message conversion, with no network request or tool execution. Raw tool_calls, tool_call_id, and host-attached data are not forwarded.

TypeScript

import { Support } from '@jangts/agent-core';
const messages: Support.ProviderMessage[] = [
  { role: 'user', content: '查询资料' },
  { role: 'assistant', content: '', toolCalls: [
    { id: 'call-1', name: 'lookup', arguments: '{"query":"资料"}' },
  ] },
  { role: 'tool', content: '{"found":true}', toolCallId: 'call-1' },
];
console.log(Support.chatCompletionMessages(messages));

JavaScript

import { Support } from '@jangts/agent-core';
const messages = [
    { role: 'user', content: '查询资料' },
    { role: 'assistant', content: '', toolCalls: [
            { id: 'call-1', name: 'lookup', arguments: '{"query":"资料"}' },
        ] },
    { role: 'tool', content: '{"found":true}', toolCallId: 'call-1' },
];
console.log(Support.chatCompletionMessages(messages));

Related policy source

• HTTP failure mapping and controlled request fields

Related definitions

• FunctionCallDelta
• ModelPart