> For the complete documentation index, see [llms.txt](https://luadoc.edgetx.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://luadoc.edgetx.org/lua-api-programming/return-statement-syntax.md).

# Return Statement Syntax

The return statment is the last statement in an OpenTX Lua script. It defines the input/output table values and functions used to run the script.

Parameters *init*, *input* and *output* are optional. If a script doesn't use them, they can be omitted from return statement.

Example without *init* and *output*:

```lua
local inputs = { { "Aileron", SOURCE }, { "Ail. ratio", VALUE, -100, 100, 0 } }

local function run_func(ail, ratio)
    -- do some stuff
    if (ail > 50) and ( ratio < 40) then
        playFile("foo.wav")    
    end
end

-- script that only uses input and run
return { run=run_func, input=inputs }
```


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://luadoc.edgetx.org/lua-api-programming/return-statement-syntax.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.