Fix: AI Agent Goes Silent After Greeting

If your Dialora AI agent greets the caller but then goes completely silent or stops responding, you're experiencing one of the most commonly reported issues in our support queue. The good news: this problem is almost always fixable with a few simple adjustments.

Quick Fix Summary

The fastest solution is to switch your model from GPT Nano to GPT 4.1-mini. If that doesn't resolve it, check your OpenAI API key balance and simplify your agent's prompt. Most silent agent issues are resolved within 5 minutes using these steps.

Why Your Agent Goes Silent

When an AI agent greets successfully but then stops responding, it indicates the model can process the initial prompt but fails during conversation continuation. Here are the four most common causes:

1. GPT Nano Model Limitations (Most Common)

GPT Nano is extremely cost-effective but severely limited in reasoning ability. While it might complete basic greetings, it frequently fails when:

• Processing follow-up conversation
• Making decisions from user input
• Accessing knowledge bases or integrations
• Handling unexpected caller responses

This accounts for approximately 60% of all silent agent reports.

2. Exhausted OpenAI API Key Credits

If you've connected your own OpenAI API key (BYO key), it may have run out of credits. When your key has zero remaining balance, the agent:

• Successfully uses cached prompts for the greeting
• Fails silently when trying to generate responses
• Never produces an error message just stops talking

3. Overly Complex Prompts

Prompts that are too detailed, contain contradictory instructions, or ask the agent to perform too many simultaneous tasks can cause processing failures. GPT Nano struggles most with complexity.

4. Knowledge Base Size Issues

A knowledge base that's too large can cause response timeouts, making the agent appear silent while it's actually timing out trying to retrieve information.

Step-by-Step Solution

Follow these steps in order until your agent responds:

Step 1: Check and Change Your Model

1. Log into your Dialora dashboard
2. Navigate to Agent Settings → Model Configuration
3. Check your current model selection
4. If using GPT Nano, click to change it
5. Select GPT 4.1-mini (recommended for most use cases)
6. Click Save Changes
7. Test your agent with a test call

Expected result: Agent should respond throughout the entire conversation.

Step 2: Verify Your OpenAI API Key (If Using BYO)

If you've connected your own OpenAI API key:

1. Go to Integrations → API Keys
2. Log into your OpenAI account at platform.openai.com
3. Navigate to Billing → Usage
4. Check your remaining credits and usage
5. If credits are exhausted:Either top up your OpenAI account, ORRemove your custom key to use Dialora's default model endpoint
6. Click Remove API Key if exhausted, then re-test

Expected result: Agent uses Dialora's infrastructure instead of your exhausted key.

Step 3: Simplify Your Prompt

Complex prompts are a major culprit with GPT Nano. Simplify by:

1. Go to Agent Settings → Prompt & Behavior
2. Review your current system prompt
3. Remove any multi-step conditional logic
4. Delete references to external tools or APIs (if not actively used)
5. Test with a basic prompt first:

You are a helpful customer service agent. Answer caller questions clearly and concisely. Be friendly and professional.

1. Save and test with a phone call
2. Once working, gradually add back complexity (one section at a time)

Step 4: Test with a Basic Prompt First

Start with the simplest possible configuration:

• Model: GPT 4.1-mini
• Prompt: Basic greeting and assistant behavior only
• No knowledge base connected
• No complex integrations

Make a test call. Your agent should respond to everything you say. Then incrementally add features back.

Prevention Tips

Avoid silent agents in the future:

• Always use GPT 4.1-mini or GPT 4.1: Only use GPT Nano if you're certain your use case doesn't require complex reasoning
• Monitor OpenAI key balance: If using a BYO key, set up billing alerts and check credits weekly
• Keep prompts focused: Aim for under 500 words, with clear, simple instructions
• Test knowledge bases: If adding a large knowledge base (500+ documents), test incrementally
• Regular testing: Do weekly test calls with different scenarios to catch issues early

When to Contact Support

Reach out to the Dialora support team if:

• You've tried all steps above and the agent still goes silent
• You're seeing error messages (instead of just silence)
• The issue appears only with certain numbers or calls types
• You need help simplifying a complex prompt

Contact: support@dialora.ai