ValidationException when using bedrock model with multi-agent

[tersimdev]

Not sure if this is a bug, some mistake on my end, or weird LLM io.
EDIT: Converted to issue.

Test code:

import "dotenv/config.js";
import { tool } from "llamaindex";
import { multiAgent, agent } from "@llamaindex/workflow";
import { z } from "zod";
import { Bedrock } from '@llamaindex/aws';


const claude = new Bedrock({
    model: process.env.CLAUDE_3_SONNET_MODEL_ID as string, // same as BEDROCK_MODELS.ANTHROPIC_CLAUDE_3_SONNET
    region: process.env.BEDROCK_REGION, //i have tried with both apac and us models
    credentials: {
      accessKeyId: process.env.AWS_ACCESS_KEY_ID as string,
      secretAccessKey: process.env.AWS_SECRET_ACCESS_KEY as string
    }
});

// Create a weather agent
const weatherAgent = agent({
  name: "WeatherAgent",
  description: "Provides weather information for any city",
  tools: [
    tool(
      {
        name: "fetchWeather",
        description: "Get weather information for a city",
        parameters: z.object({
          city: z.string(),
        }),
        execute: ({ city }) => `The weather in ${city} is sunny`,
      }
    ),
  ],
  llm: claude,
  verbose: true,
});

const jokeTool = tool(() => "Baby Llama is called cria", {
  name: "joke",
  description: "Use this tool to get a joke",
});

// Create a joke-telling agent
const jokeAgent = agent({
  name: "JokeAgent",
  description: "Tells jokes and funny stories",
  tools: [jokeTool], // Using the joke tool defined earlier
  llm: claude, //claude doesnt work!
  canHandoffTo: [weatherAgent], // Can hand off to the weather agent
  verbose: true,
});

// Create the multi-agent workflow
const agents = multiAgent({
  agents: [jokeAgent, weatherAgent],
  rootAgent: jokeAgent, // Start with the joke agent
  verbose: true,
});

// Run the workflow
const result = await agents.run(
  "Give me a morning greeting with a joke and the weather in San Francisco"
);
console.log(result.data.result);

Output:

[Agent JokeAgent]: Starting agent
<path>\llamaindex-test\node_modules\@aws-sdk\client-bedrock-runtime\dist-cjs\index.js:1750
  const exception = new ValidationException({
                    ^

ValidationException: Malformed input request: #: subject must not be valid against schema {"required":["messages"]}#/tools/0: required key [input_schema] not found#/tools/0: required key [type] not found#/tools/0: extraneous key [description] is not permitted#/tools/0/name: #/tools/0/name: joke is not a valid enum value#/tools/0: required key [type] not found#/tools/0: required key [display_height_px] not found#/tools/0: required key [display_width_px] not found#/tools/0: extraneous key [description] is not permitted#/tools/0/name: #/tools/0/name: joke is not a valid enum value#/tools/0: required key [type] not found#/tools/0: extraneous key [description] is not permitted#/tools/0/name: #/tools/0/name: joke is not a valid enum value, please reformat your input and try again.
    at de_ValidationExceptionRes (<path>llamaindex-test\node_modules\@aws-sdk\client-bedrock-runtime\dist-cjs\index.js:1750:21)
    at de_CommandError (<path>llamaindex-test\node_modules\@aws-sdk\client-bedrock-runtime\dist-cjs\index.js:1567:19)
    at process.processTicksAndRejections (node:internal/process/task_queues:105:5)
    at async <path>\llamaindex-test\node_modules\@smithy\middleware-serde\dist-cjs\index.js:36:20
    at async <path>\llamaindex-test\node_modules\@smithy\core\dist-cjs\index.js:193:18
    at async <path>\llamaindex-test\node_modules\@smithy\middleware-retry\dist-cjs\index.js:320:38
    at async <path>\llamaindex-test\node_modules\@aws-sdk\middleware-logger\dist-cjs\index.js:33:22
    at async Bedrock.streamChat (<path>/llamaindex-test/node_modules/@llamaindex/aws/dist/llm/bedrock/index.js:1481:26)
    at async response.<computed> (<path>/llamaindex-test/node_modules/@llamaindex/core/decorator/dist/index.js:90:34)
    at async FunctionAgent.takeStep (<path>/llamaindex-test/node_modules/@llamaindex/workflow/dist/index.js:94:26) {
  '$fault': 'client',
  '$metadata': {
    httpStatusCode: 400,
    requestId: '33d21fd9-d94e-4795-9208-e75b066d97f0',
    extendedRequestId: undefined,
    cfId: undefined,
    attempts: 1,
    totalRetryDelay: 0
  }
}

Node.js v22.15.0

[tersimdev]

When running weatherAgent as the root agent, there is no error but the joke tool is not used.

[Agent WeatherAgent]: Starting agent
[Agent WeatherAgent]: No tool calls to process, returning final response


Good morning! Here's a joke to start your day with a smile: Why can't a bicycle stand up by itself? It's two-tired!

And for the weather in San Francisco, it's sunny today. Perfect for getting outside and enjoying the beautiful city.