I’ve been going back-and-forth with the support team at VAPI, on a rather complicated IVR flow for an AI receptionist. I have multiple tools/functions that sometimes pass the correct arguments and other times does not. Looking for somebody a bit more hands-on to spend time on a call to look at the prompt and help me build solid guard rails to keep it within the confines of the chat flow.

Hi there! 👋 I understand you're working on a complicated IVR flow for an AI receptionist in VAPI and facing challenges with tools/functions not consistently passing the correct arguments. While I can't arrange a hands-on call for you, I can definitely provide some guidance on building solid guard rails for your IVR flow based on the information I have. Here are some strategies to help you build guard rails and ensure correct argument passing: ## Prompt Engineering Techniques According to the [VAPI Prompting Guide](https://docs.vapi.ai/prompting-guide), effective prompt engineering involves: - **Sectional Organization**: Break down prompts into sections like Identity, Style, Response Guidelines, and Task & Goals to enhance clarity and control the AI's behavior. - **Step-by-Step Instructions**: Provide a sequence of steps for complex interactions to ensure a structured conversation flow. - **Explicit Tool Integration**: Specify when and how to use external tools or APIs to ensure accurate invocation. - **Fallback and Error Handling**: Include fallback options and error-handling mechanisms to handle unexpected inputs or errors gracefully. ## Ensuring Correct Argument Passing To ensure tools and functions pass the correct arguments: 1. **Explicit Tool Integration**: Clearly define the purpose and expected arguments for each tool in your prompts. 2. **Correct Variable Usage**: - Use proper syntax for variable interpolation (double curly braces

{{ }}

) - Verify the variable is in the correct scope and accessible - Ensure blocks are executed in the correct order 3. **JSON Response Format**: - Ensure responses include the correct

toolCallId

and

result

fields - Format JSON responses as strings without line breaks 4. **Tool Configuration**: - Set the

async

parameter to

true

for asynchronous processing if needed - Configure server secrets properly for authentication ## Troubleshooting Methods When things aren't working as expected:

Structure your prompt clearly with defined roles, tone, and step-by-step task flow, explicitly instruct when and how to use tools, add fallback logic for errors, and control timing between responses https://docs.vapi.ai/prompting-guide