@BindTool

The @BindTool(ToolClass, options?) method decorator ("@agboss/core") binds a method on a workflow provider class to a @Tool or @McpTool (optionally scoped to a specific @Agent via { agent: MyAgent }).

@BindTool example

src/tools/bound-search.service.ts

import { Agent, BindTool, Injectable, Tool, type ToolHandler } from "@agboss/core";
import { ListOf, Text } from "@agboss/core/dto";

export class RegionalSearchInputDto {
  @Text({ prompt: "Role keywords, e.g. Staff TypeScript" })
  query!: string;
}

export class RegionalSearchOutputDto {
  @ListOf(Text, { prompt: "Matching role titles" })
  openings!: string[];
}

@Tool({
  name: "search_regional_jobs",
  description: "Searches openings in a target region",
  input: RegionalSearchInputDto,
  output: RegionalSearchOutputDto,
})
export class SearchRegionalJobsTool
  implements ToolHandler<RegionalSearchInputDto, RegionalSearchOutputDto>
{
  run(input: RegionalSearchInputDto): Promise<RegionalSearchOutputDto> {
    return Promise.resolve({ openings: [`Global: ${input.query}`] });
  }
}

@Agent({
  name: "eu-scout-agent",
  description: "Finds EU roles using SearchRegionalJobsTool",
  model: "moonshotai/kimi-k2.6",
  prompt: "Call search_regional_jobs to find matching roles in Europe.",
  tools: [SearchRegionalJobsTool],
})
export class EuScoutAgent {}

@Injectable()
export class EuJobSearchBindings {
  @BindTool(SearchRegionalJobsTool, { agent: EuScoutAgent })
  searchForEuAgent(input: RegionalSearchInputDto): Promise<RegionalSearchOutputDto> {
    return Promise.resolve({ openings: [`EU: ${input.query}`] });
  }
}

test/bound-search.service.test.ts

import { expect, it } from "vitest";
import { testTool } from "@agboss/core/testing";
import {
  EuJobSearchBindings,
  SearchRegionalJobsTool,
} from "../src/tools/bound-search.service.js";

it("executes default tool handler and bound EU override method", async () => {
  const runTool = testTool(SearchRegionalJobsTool);
  const { output: globalOut } = await runTool({ query: "Staff TypeScript" });
  expect(globalOut.openings).toEqual(["Global: Staff TypeScript"]);

  const bindings = new EuJobSearchBindings();
  const euOut = await bindings.searchForEuAgent({ query: "Staff TypeScript" });
  expect(euOut.openings).toEqual(["EU: Staff TypeScript"]);
});

How to configure @BindTool options and signatures

Parameter	Type	Required	Description
tool	Class | string	Yes	The @Tool / @McpTool class (or snake_case tool name string) handled or intercepted by this method.
options.agent	Class | string	No	Optional @Agent class (or kebab-case agent name) restricting the binding to calls made by that specific agent.