Custom GPT vs AskVault - building a support bot yourself or buying one
What people mean by "custom ChatGPT"
There are three common versions, and they are very different projects.
- An OpenAI custom GPT. Built inside ChatGPT in an afternoon. Visitors need a ChatGPT account to use it, and it cannot be embedded on your site as a chat widget.
- A bot on the OpenAI API. Your developers write the crawler, the retrieval, the chat window and the hosting.
- A full homegrown stack. An LLM API, a vector database, a React chat window and a team to keep it running.
What a customer support bot actually needs
A support bot that faces customers needs a lot more than a chat box. Here is what a support lead typically needs, and where each option stands.
| Need | Custom GPT | DIY on the API | AskVault |
|---|---|---|---|
| Embeds on your website | No | Yes, once built | Yes, one script tag |
| Answers cite their sources | Inconsistent | If you build it | On by default |
| Says "I don't know" instead of guessing | Prompt-dependent | If you build it | Built in, with a gap report |
| Hands off to a human | No | If you build an inbox | Live chat inbox, Growth+ |
| WhatsApp, Telegram, Slack, SMS | No | One project per channel | Included from Growth |
| Verifies logged-in customers | No | If you build it | HMAC identity verification |
| Order lookups for Shopify or WooCommerce | No | Custom code | Ready-made skills, Growth+ |
| Usable from Claude Desktop or Cursor | No | Custom code | Opt-in MCP server per workspace |
| Time to first answer | Minutes, inside ChatGPT only | Weeks | Minutes for a small site; larger sites take longer to index |
Cost: where the money really goes
The model calls are rarely the expensive part of a homegrown bot. The expensive parts are the weeks of developer time to build crawling, retrieval, a widget, citations and an inbox, then the ongoing time to fix the crawler when a site changes, handle a WhatsApp API update, or chase a wrong answer.
AskVault plans are flat: Free at $0 for 50 messages, 5 MB and 1 workspace, Starter at $39, Growth at $99 and Business at $249 a month, with live prices on the pricing page. Enterprise is quoted. If a developer's time costs you more than a few hundred dollars a week, buying usually wins in the first month.
When building your own still makes sense
- An internal bot for a small team with no customer-facing surface and no compliance questions. A custom GPT is quick.
- One narrow workflow, such as a code-review helper for a single repository, where a general support platform adds nothing.
- A one-week experiment to prove people will use a bot before you pick a platform.
Moving from a homegrown bot
- Paste your site URL into AskVault onboarding and upload your files to the Knowledge.
- Copy your system prompt into AI settings and adjust it to your tone.
- Compare answers to the same 20 questions in the chat playground.
- Swap your chat window for the AskVault widget snippet, then add messaging channels.
FAQ
Can I use a custom GPT as a website chatbot?
No. Custom GPTs live inside ChatGPT and require visitors to sign in there.
Is building on the OpenAI API cheaper?
The API calls are cheap. The engineering and upkeep usually cost far more than a platform subscription.
Does AskVault use OpenAI models?
AskVault routes chat across several providers. Paid workspaces choose their model, and no API key is needed.
What if I only want a simple chat box?
Use the Free plan: 50 messages a month and a website widget, no card required.
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