> ## Documentation Index
> Fetch the complete documentation index at: https://docs.contextaco.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Security and privacy

> What is private by default, what a token can do, and what publishing actually means.

Contextaco holds working notes, which are often the most sensitive thing a team writes down — the
decisions, the constraints, the things that did not work. This page states plainly what is protected
and what is not.

## Private by default

Everything you create is private. Publishing is a deliberate act, never a side effect of writing,
sharing a link, or connecting a new agent.

A private taco returns **not found** to anyone else — not *forbidden*. Saying "this exists but you
may not see it" is itself a disclosure, so the answer to someone not entitled to know is the same
answer they would get for something that never existed.

## What a published taco means

Anyone can read it and fork it, with no account. Treat it as irreversible in practice: a fork
someone else made is theirs, and it stays theirs if you later make yours private again.

<Warning>
  **An agent holding your credentials can publish for you.** Changing visibility is a normal
  capability, not a privileged one, so an agent that misreads "share this with the team" could make
  a private taco public. Ask agents to confirm before publishing — good ones will.
</Warning>

## Connecting: two paths, and one is better

<Tabs>
  <Tab title="Browser sign-in (preferred)">
    Your client registers itself, sends you through a sign-in, and you approve the connection once.
    **Nothing is copied anywhere** — there is no key to paste, lose, or leak into a shell history.
    Use this whenever the client supports it.
  </Tab>

  <Tab title="Token (headless only)">
    For CI, a headless machine, or a client with no connector support. A token is shown once, when
    created; if you lose it, revoke it and make another. There is no way to read it back, which is
    the property that makes revoking it meaningful.
  </Tab>
</Tabs>

## What a token can and cannot do

A token **acts as you**. Be deliberate about which agent gets one.

| It can                                                                       | It cannot                                                   |
| ---------------------------------------------------------------------------- | ----------------------------------------------------------- |
| Read everything you own, including private work                              | Create or revoke credentials — that happens on the web only |
| Write, edit and delete notes                                                 | Set or change your handle, which is chosen once, by you     |
| Attach and delete files                                                      | Read anything you cannot read yourself                      |
| Fork, and change a taco's visibility — including making a private one public | Act after you revoke it                                     |

**One token per agent.** That is the whole point: it lets you cut off a single machine without
disturbing anything else. A shared token turns every revocation into an outage.

## History, deletion and what survives

* **Notes** can be deleted, but content that was already checkpointed keeps that history. That is
  what makes the record trustworthy — a history that can be quietly rewritten is not evidence.
* **Files** are the opposite: deleting one is immediate and permanent, with nothing to fall back on.
  That is also what makes storage reclaimable.
* Deleting a file that a note still shows is **refused**, and the refusal names the notes, so you
  are never one command away from leaving a body pointing at nothing.

## Where the data lives

Contextaco stores and serves. **It makes no model calls of its own** — your agent does the
reasoning, so your content is not sent to a model by us as a side effect of being stored.

Full detail, including the operating entity and how to reach us:
[Privacy](https://contextaco.com/privacy) · [Terms](https://contextaco.com/terms).