---
title: Troubleshooting
description: Debug and resolve common issues with Workers AI embedded function calling.
image: https://developers.cloudflare.com/dev-products-preview.png
---

> Documentation Index  
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# Troubleshooting

This section will describe tools for troubleshooting and address common errors.

## Logging

General [logging](https://developers.cloudflare.com/workers/observability/logs/) capabilities for Workers also apply to embedded function calling.

### Function invocations

The invocations of tools can be logged as in any Worker using `console.log()`:

Logging tool invocations

```
export default {  async fetch(request, env, ctx) {    const sum = (args: { a: number; b: number }): Promise<string> => {      const { a, b } = args;      // Logging from within embedded function invocations      console.log(`The sum function has been invoked with the arguments a: ${a} and b: ${b}`)      return Promise.resolve((a + b).toString());    };    ...  }}
```

### Logging within `runWithTools`

The `runWithTools` function has a `verbose` mode that emits helpful logs for debugging of function calls as well input and output statistics.

Enabled verbose mode

```
const response = await runWithTools(  env.AI,  '@hf/nousresearch/hermes-2-pro-mistral-7b',  {    messages: [      ...    ],    tools: [      ...    ],  },  // Enable verbose mode  { verbose: true });
```

## Performance

To respond to a LLM prompt with embedded function, potentially multiple AI inference requests and function invocations are needed, which can have an impact on user experience.

Consider the following to improve performance:

* Shorten prompts (to reduce time for input processing)
* Reduce number of tools provided
* Stream the final response to the end user (to minimize the time to interaction). See example below:

Streamed response example

```
async fetch(request, env, ctx) {  const response = (await runWithTools(    env.AI,    '@hf/nousresearch/hermes-2-pro-mistral-7b',    {      messages: [        ...      ],      tools: [        ...      ],    },    {      // Enable response streaming      streamFinalResponse: true,    }  )) as ReadableStream;
  // Set response headers for streaming  return new Response(response, {    headers: {      'content-type': 'text/event-stream',    },  });}
```

## Common Errors

If you are getting a `BadInput` error, your inputs may exceed our current context window for our models. Try reducing input tokens to resolve this error.

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