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

# Vayl

<button type="button" class="button primary" data-action="ask" data-icon="gitbook-assistant">Ask a question…</button>

<button type="button" class="button secondary" data-action="ask" data-query="How do I connect Vayl to my MCP client" data-icon="bolt">Get started</button><button type="button" class="button secondary" data-action="ask" data-query="What is reconciling memory" data-icon="book">What is reconciling memory?</button><button type="button" class="button secondary" data-action="ask" data-query="How do I scope memory per user" data-icon="sitemap">Scope per user</button>

<table data-view="cards"><thead><tr><th></th><th></th><th></th><th data-hidden data-card-target data-type="content-ref"></th></tr></thead><tbody><tr><td><h4><i class="fa-rocket-launch" style="color:$primary;">:rocket-launch:</i></h4></td><td><strong>Documentation</strong></td><td>Install Vayl, learn the core concepts, and deploy a team server.</td><td></td></tr><tr><td><h4><i class="fa-terminal" style="color:$primary;">:terminal:</i></h4></td><td><strong>MCP tools</strong></td><td>Every tool your agent gets — memory, safety, accountability, and compliance.</td><td></td></tr><tr><td><h4><i class="fa-github" style="color:$primary;">:github:</i></h4></td><td><strong>Open source</strong></td><td>Vayl is Apache-2.0 and built in the open. Read the code and contribute.</td><td><a href="https://github.com/vayl-dev/vayl">https://github.com/vayl-dev/vayl</a></td></tr></tbody></table>

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{% column width="50%" %}

## Memory that stays current

Most agent memory accumulates — it saves every fact and later hands your agent a stale one. Vayl **reconciles on write**: a new value supersedes the old, a removal actually retracts, ambiguous inputs are flagged instead of guessed, and the full history stays queryable and auditable.

It speaks the Model Context Protocol, so any MCP client plugs in — with SQLite by default and no server to run.

{% hint style="info" icon="sparkles" %}
**New to reconciling memory?**

Ask the Assistant how supersede, retract, and the same-slot invariant work.

<button type="button" class="button primary" data-action="ask" data-query="Explain reconciling memory and the same-slot invariant" data-icon="gitbook-assistant">Explain reconciling memory</button>
{% endhint %}

<a class="button primary" data-icon="rocket-launch">Get started</a> <a href="https://github.com/vayl-dev/vayl" class="button secondary" data-icon="github">GitHub</a>
{% endcolumn %}

{% column width="50%" %}
{% stepper %}
{% step %}

#### Install

```bash
pip install vayl-mcp
```

{% endstep %}

{% step %}

#### Add Vayl to your MCP client

{% code overflow="wrap" %}

```json
{
  "mcpServers": {
    "vayl": {
      "command": "vayl-mcp",
      "env": {
        "OPENAI_API_KEY": "sk-…",
        "VAYL_DB": "/absolute/path/vayl.db"
      }
    }
  }
}
```

{% endcode %}
{% endstep %}

{% step %}

#### Watch it reconcile

```
"We use Redux."                  → remembered
"Actually, we switched to Zustand."  → Redux retired, Zustand active
"What do we use?"                → "Zustand"
```

{% endstep %}
{% endstepper %}
{% endcolumn %}
{% endcolumns %}

<h2 align="center">Open source, built in the open</h2>

<p align="center">Vayl is Apache-2.0. Read the code, file an issue, or open a pull request.</p>

<table data-card-size="large" data-view="cards"><thead><tr><th></th><th></th><th></th><th data-hidden data-card-target data-type="content-ref"></th></tr></thead><tbody><tr><td><h4><i class="fa-github">:github:</i></h4></td><td><strong>GitHub</strong></td><td>The engine, the MCP server, and the benchmarks — all open source.</td><td><a href="https://github.com/vayl-dev/vayl">https://github.com/vayl-dev/vayl</a></td></tr><tr><td><h4><i class="fa-shield-halved">:shield-halved:</i></h4></td><td><strong>Security &#x26; compliance</strong></td><td>Encrypted at rest, tamper-evident audit chain, and GDPR building blocks.</td><td></td></tr></tbody></table>


---

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