InvocationMetadata

CORE · interface · Type contract

Identity and timing shared by every invocation receipt.

Import

TypeScript

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

JavaScript

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

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

Definition

interface InvocationMetadata

Field structure

Field	Type	Required	Description
runId	string | undefined	Optional	Read-only. Root run this invocation belongs to, when the host runs inside a diagnostics scope.
spanId	string | undefined	Optional	Read-only. Diagnostics span of this invocation.
parentSpanId	string | undefined	Optional	Read-only. Span that caused this invocation; absent for a root invocation.
parentInvocationId	string | undefined	Optional	Read-only. Enclosing invocation when one call triggers another.
invocationId	string	Required	Read-only. Opaque per-invocation id shared by receipt, events and diagnostic records.
startedAtMs	number	Required	Read-only. Start instant in epoch milliseconds.
durationMs	number	Required	Read-only. Elapsed milliseconds from start to completion.

Examples

• ContextJournal: the in-request projection of receipts: Turn real call receipts into in-request records usable in later context, without starting another persistent logging system.
• ModelRunner: input can be shortened while the output contract stays the same: Execute one model interaction through the real Provider port and return a value plus the invocation for this call.
• Real tool invocation and in-request runtime: Core registers and executes real tools and returns receipts carrying an invocation; business authorization is owned by the implementation registered by the App.

Read the model receipt already recorded by the Runner

Beginner · Node.js

TypeScript

import { ModelRunner } from '@jangts/agent-core';
const runner = new ModelRunner({ provider: { async *stream() { yield '服务运行正常'; } } });
const result = await runner.invoke('查询服务状态');
console.log(result.invocation.invocationId);
console.log(runner.journal.snapshot());

JavaScript

import { ModelRunner } from '@jangts/agent-core';
const runner = new ModelRunner({ provider: { async *stream() { yield '服务运行正常'; } } });
const result = await runner.invoke('查询服务状态');
console.log(result.invocation.invocationId);
console.log(runner.journal.snapshot());

An App adapter records the local tool it actually executes

Configuration · Node.js

TypeScript

import { ContextJournal } from '@jangts/agent-core/journal';
const journal = new ContextJournal();
const invocationId = journal.beginTool({ toolId: 'get_status', input: {} });
// 此处由 App 实际执行本地读取；不是模型提供的回执。
const status = '服务运行正常';
journal.finishTool({ invocationId, status: 'success', value: status });
console.log(journal.snapshot());

JavaScript

import { ContextJournal } from '@jangts/agent-core/journal';
const journal = new ContextJournal();
const invocationId = journal.beginTool({ toolId: 'get_status', input: {} });
// 此处由 App 实际执行本地读取；不是模型提供的回执。
const status = '服务运行正常';
journal.finishTool({ invocationId, status: 'success', value: status });
console.log(journal.snapshot());

Related policy source

• Core default budget values
• Check order for tool input, execution, output, and late results