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

# Installation

> Detailed setup, project layout, and how to run the test suite.

## Requirements

* Python 3.10 or newer
* No other runtime dependencies for the interpreter itself. `pytest` is
  only needed if you want to run the test suite.

<Warning>
  Sense has no compiled/bytecode form yet — the reference implementation is a
  tree-walking interpreter. This is a deliberate Phase 1 simplification (see
  [Roadmap](/roadmap)), not a permanent constraint on the language.
</Warning>

## Install

```bash theme={null}
pip install sense-lang
```

That's it — no other runtime dependency for the interpreter itself. Add
`[anthropic]` (`pip install sense-lang[anthropic]`) or `[openai]` if you
want to use
[`inference(...)`](/ai-native/model-ask-answer#real-providers-inference-provider-model-id)
with that provider — both are optional because picking `inference("mock",
...)` instead of a real provider is what keeps a program offline, not
something `ask()` does on its own; neither extra is needed for that path.
Add `[mcp]`
similarly for [`connect_mcp(...)`](/ai-native/mcp)
(`pip install sense-lang[anthropic,openai,mcp]` for everything).

## Verify it worked

```bash theme={null}
sense --version
```

```txt theme={null}
sense 0.20.0
```

If `sense` isn't on your `PATH`, call the module directly instead:
`python -m sense_lang run fib.sns`.

## Building from source

Only needed for contributing to Sense itself — running programs doesn't
require it.

```bash theme={null}
git clone <repo-url>
cd sense
python -m venv .venv
```

<CodeGroup>
  ```bash Windows theme={null}
  .venv\Scripts\python -m pip install -e .[dev]
  ```

  ```bash macOS / Linux theme={null}
  source .venv/bin/activate
  pip install -e .[dev]
  ```
</CodeGroup>

The `[dev]` extra pulls in `pytest`:

```bash theme={null}
pytest -q
```

Covers the lexer (indentation tracking included), parser, interpreter
semantics, error paths, agent pause/resume, and every example program.

<Frame>
  ```txt theme={null}
  sense/
    docs/               This documentation site (Mintlify)
    src/sense_lang/      The interpreter: lexer, parser, AST, environment,
                         interpreter, CLI
    examples/           Runnable .sns programs, one per major feature
    tests/              The pytest suite
  ```
</Frame>

## Previewing this site locally

This is a standard [Mintlify](https://mintlify.com) project (`docs.json` +
MDX pages), live at [docs.sensecode.dev](https://docs.sensecode.dev):

1. Install the CLI: `npm i -g mint`
2. Preview locally: `mint dev` from inside `docs/` (defaults to
   `http://localhost:3000`)

<Note>
  As of this writing, `npx mint@latest` intermittently fails to resolve one
  of its own internal dependency versions (`@mintlify/models`) — an
  upstream registry issue, not something wrong with this project. If `mint
    dev` fails to install, it's worth simply retrying, or pinning an explicit
  recent `mint` version.
</Note>