ModelProviderContext

CORE · interface · Type contract

Per-call facts a provider receives besides the messages themselves.

Import

TypeScript

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

JavaScript

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

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

Definition

interface ModelProviderContext

Extends or implements: ExecutionContext.

Field structure

Field	Type	Required	Description
options	Readonly<ModelOptions> | undefined	Optional	Read-only. Options prepared for this call, including function schemas and JSON mode.
logger	SubFlowLog | undefined	Optional	Read-only. Explicit optional recorder for this operation; never inferred from diagnostics.
signal	AbortSignal	Required	Read-only. Non-optional cancellation signal; never undefined once execution has started.
diagnostics	DiagnosticContext | undefined	Optional	Read-only. Diagnostic scope of the enclosing call, when recording is enabled.

Examples

• Model tools and transports: typed selection only after full validation: A tool definition provides a Schema and resolver; a transport translates wire output into the unified model selection contract.
• Compatible Provider and custom Providers: Support owns the common Chat Completions HTTP/SSE lifecycle; an App can substitute its own ChatProvider.
• Provider observation and the App's own recording targets: A stable Provider binds observation rules; each request is associated only with its own target, and child scopes inherit the association.

Declare two selectable tools

Beginner · Node.js

TypeScript

import { ModelToolRegistry } from '@jangts/agent-core';
const inputSchema = { jsonSchema: { type: 'object', properties: {}, additionalProperties: false },
  parse(value: unknown) {
    if (!value || typeof value !== 'object' || Array.isArray(value) || Object.keys(value).length) throw new Error('需要空对象');
    return {};
  } };
const tools = new ModelToolRegistry([
  { id: 'greet', description: '回答问候', inputSchema, resolve: () => 'greet' },
  { id: 'status', description: '查询状态', inputSchema, resolve: () => 'status' },
]).seal();
console.log(tools.resolve({ toolId: 'status', input: {} }, { stageId: 'recognize' }));

JavaScript

import { ModelToolRegistry } from '@jangts/agent-core';
const inputSchema = { jsonSchema: { type: 'object', properties: {}, additionalProperties: false },
    parse(value) {
        if (!value || typeof value !== 'object' || Array.isArray(value) || Object.keys(value).length)
            throw new Error('需要空对象');
        return {};
    } };
const tools = new ModelToolRegistry([
    { id: 'greet', description: '回答问候', inputSchema, resolve: () => 'greet' },
    { id: 'status', description: '查询状态', inputSchema, resolve: () => 'status' },
]).seal();
console.log(tools.resolve({ toolId: 'status', input: {} }, { stageId: 'recognize' }));

Project an allowed subset to only one stage

Configuration · Node.js

TypeScript

import { ModelToolRegistry, Support } from '@jangts/agent-core';
const schema = Support.defineSchema({ jsonSchema: { type: 'object', properties: {} },
  parse(value: unknown) { if (!value || typeof value !== 'object' || Array.isArray(value)) throw new TypeError('需要对象'); return {}; } });
const registry = new ModelToolRegistry([
  { id: 'greet', description: '问候', inputSchema: schema, resolve: () => 'greet' },
  { id: 'status', description: '状态', inputSchema: schema, resolve: () => 'status' },
]).seal();
const readOnly = registry.select(['status']);
const transport = Support.createModelTransport({ id: 'recognize', tools: readOnly });
console.log(transport.id, readOnly.ids());

JavaScript

import { ModelToolRegistry, Support } from '@jangts/agent-core';
const schema = Support.defineSchema({ jsonSchema: { type: 'object', properties: {} },
    parse(value) { if (!value || typeof value !== 'object' || Array.isArray(value))
        throw new TypeError('需要对象'); return {}; } });
const registry = new ModelToolRegistry([
    { id: 'greet', description: '问候', inputSchema: schema, resolve: () => 'greet' },
    { id: 'status', description: '状态', inputSchema: schema, resolve: () => 'status' },
]).seal();
const readOnly = registry.select(['status']);
const transport = Support.createModelTransport({ id: 'recognize', tools: readOnly });
console.log(transport.id, readOnly.ids());

Related policy source

• HTTP failure mapping and controlled request fields

Related definitions

• DiagnosticContext
• ExecutionContext
• ModelOptions
• SubFlowLog