> For the complete documentation index, see [llms.txt](https://cjay-1.gitbook.io/synapse-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://cjay-1.gitbook.io/synapse-docs/welcome-to-synapse.md).

# Welcome to Synapse

**Expertise you can ship.**

Synapse turns what an expert knows into a single signed file that people, programs and AI agents can use, check and license. It needs no account, no API key, no database and no server. Try it in one command:

```bash
synapse demo
```

## The problem

Knowledge is hard to hand over in a form that can be trusted.

* A **PDF or wiki page** loses who said it, which version it was, and whether anyone tested it.
* A **chatbot** answers fluently and sometimes invents things. There is no way to tell which parts came from the expert.
* A **licence in a contract** is a sentence that nobody can check automatically. Nothing records how the knowledge was used, and a file that has been quietly edited looks the same as the original.

Synapse replaces these with a **capsule**.

## What a capsule is

A capsule is one JSON file that holds an expert's *approved* knowledge. It is:

| Property           | What it means                                                                                                                            |
| ------------------ | ---------------------------------------------------------------------------------------------------------------------------------------- |
| **Cited**          | Every item carries the exact words it came from, with their position in the source document.                                             |
| **Attributed**     | Every item names its contributor. Contributors can co-sign the file.                                                                     |
| **Tested**         | It cannot be published until it passes an evaluation. The result is recorded inside it.                                                  |
| **Honest**         | It answers from the expert's own approved words, or says it does not cover the question. There is no model inside it to invent anything. |
| **Tamper-evident** | Change one character and the file no longer opens.                                                                                       |
| **Versioned**      | Each version's hash is chained to the one before.                                                                                        |
| **Licensable**     | A signed license file says who may use it, for what, how many times and until when.                                                      |

## Three ways to use the same file

| Who         | How                                                                                         |
| ----------- | ------------------------------------------------------------------------------------------- |
| A person    | `synapse ask capsule.json "your question"`                                                  |
| A program   | `synapse.Open("capsule.json")` then `Ask(...)` in Go, or the HTTP gateway from any language |
| An AI agent | `synapse mcp capsule.json` makes the capsule a tool for Claude, Cursor and others           |

## Why it needs no setup

| Usually needed                | In Synapse                                                                                                                  |
| ----------------------------- | --------------------------------------------------------------------------------------------------------------------------- |
| An account                    | Your identity is a Stellar key pair generated on your machine the first time you need it                                    |
| API keys                      | There is no model to call and no service to log in to                                                                       |
| A database                    | Capsules, licenses and usage logs are files                                                                                 |
| A server                      | Files are checked offline. A gateway is optional, for when you must enforce limits yourself                                 |
| A wallet and blockchain setup | The same key is already a Stellar account. A shared public deployment is built in and new accounts are funded automatically |
| Environment variables         | None. `SYNAPSE_HOME` can move the folder, but nothing requires it                                                           |

## Where Stellar fits

Synapse works without Stellar. Stellar adds a **public record that neither side controls**, through three small Soroban contracts with no admin and no fees:

1. an **anchor** for every capsule version, so a buyer can prove the file they hold is the one the owner published;
2. the **grant and revocation** of a license, which anyone can check;
3. **receipts** for sealed batches of usage, so use can be shown without revealing a single question.

Only hashes, counts and times go on-chain. See [Record it on Stellar](/synapse-docs/guides/stellar.md) and the [smart contract reference](/synapse-docs/reference/contracts.md).

## Honest limits

* A license checked on the buyer's own machine is **cooperative**. Whoever holds the file could ignore it. Run a [gateway](/synapse-docs/guides/gateway.md) when limits must be enforced.
* Answers are **keyword-based retrieval**, not semantic search or generation. That is why they are dependable, and also why a question that shares no words with the capsule is declined. See [How answers are made](/synapse-docs/how-it-works/answers.md).
* Extracting items from documents is **heuristic**. Nothing is published until the expert approves it.
* Payment is out of scope. Synapse makes licenses unambiguous and checkable; how you charge is between you and your buyer.
* The Stellar deployment is on **Testnet**.

The full list, with what is planned, is in [Roadmap and limits](/synapse-docs/project/roadmap.md).

## Where to go next

* New here? Follow the [Quickstart](/synapse-docs/quickstart.md).
* Want the vocabulary first? Read [Core concepts](/synapse-docs/core-concepts.md).
* Publishing expertise? Start with [Publish expertise](/synapse-docs/guides/publish.md).
* Integrating Synapse in software? See [Use it from Go](/synapse-docs/guides/go.md) and the [HTTP API](/synapse-docs/reference/http-api.md).
* Worried about trust? Read the [Security model](/synapse-docs/how-it-works/security.md).


---

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