The Synthflow knowledge base: how it works, and how to load your knowledge base into it

Synthflow gives an agent knowledge bases that it searches when a condition says so. Each knowledge base holds sources (PDFs, pasted documents, web pages) and a plain-language condition saying when the agent should search it. At answer time the agent retrieves relevant snippets, never the whole knowledge base.

This page is written from Synthflow's own documentation, checked on 25 September 2026. KB Builder is not affiliated with Synthflow. Our own live calls so far ran on a different platform, so the advice below applies what we learned there; it has not been tested on Synthflow calls yet.

How the Synthflow knowledge base works

	What the docs say
Where it lives	Knowledge Bases in the dashboard; attached to an agent under Knowledge & Memory
When the agent searches	When the knowledge base is attached and its search condition applies
What you can add	PDFs, blank documents (type or paste), single web pages, website crawls, Zendesk
Markdown	Not listed; paste the text into a blank document
Retrieval	Semantic search for relevant snippets; the whole knowledge base is never loaded
Chunk size, chunks per search, size limits	Not stated in the docs
Updating	Inline editing in the dashboard; PUT on a source through the API (added June 2026)
Cost	Enterprise contracts from $30,000 a year; no separate knowledge base price stated

Each call's Actions tab shows every lookup: the query, the retrieved text and how long it took.

Where it goes wrong on calls

The condition doesn't fire. If the search condition is narrow ("when the caller asks about courses"), a question about fees or admission dates may not trigger a search at all, and the agent answers without the knowledge base.

Conflicting sources. Synthflow's docs warn that when documents conflict, the answer "may be inconsistent and depend on which document it selects". An old rate card left beside a new one is enough.

Snippets without owners. A retrieved snippet can hold a price whose product name sat in the text just before it. The agent then attaches it to whatever the caller asked about.

Messy PDFs. Synthflow notes that complex PDF layouts may not extract cleanly and suggests plain text instead.

How to load a KB Builder file into Synthflow

A KB Builder knowledge base is a Markdown file written in short sections that each name one product or service, with no conflicting versions of a fact inside it.

1. Open Knowledge Bases and create a knowledge base named after the business.
2. Set the search condition broadly, for example: "When the caller asks about the business's products, services, prices, timings, what is included, policies, location or contact details."
3. Add a blank document and paste the whole file.
4. Open the agent, go to Knowledge & Memory, choose the knowledge base, save, and publish a new version.
5. Make test calls and read the lookups in each call's Actions tab.

When the business's website changes, rebuild the file in KB Builder and replace the document's text with the new version, so there is never an old copy to conflict with.

Lines to add to the agent's prompt

These come from our own live calls:

Answer questions about the business only from the knowledge base. If it doesn't have the answer, say you will check, and give the business's phone number.
Give a price, time or rule only from a sentence that names the product or service the caller asked about.
Whenever you give a price, say the name of the product or service with it.
If the caller hasn't said which product or service they mean, ask before answering.
When the knowledge base says something has not been confirmed, say exactly that. Never guess.
Don't promise messages, callbacks or bookings unless the knowledge base says the business offers them.