# Header declarations
<a name="srgs-header"></a>

The following table shows the header declarations supported by the grammar slot type. For more information, see [ Grammar header declarations ](https://www.w3.org/TR/speech-grammar/#S4.1) in the *Speech recognition grammar specification version 1* W3C recommendation.


| Declaration | Specification requirement | XML form | Amazon Lex support | Specification | 
| --- | --- | --- | --- | --- | 
| Grammar version | Required | [4.3](https://www.w3.org/TR/speech-grammar/#S4.3): version attribute on grammar element | Required | SRGS | 
| XML namespace | Required (XML only) | [4.3](https://www.w3.org/TR/speech-grammar/#S4.3): xmlns attribute on grammar element | Required | SRGS | 
| Document type | Required (XML only) | [4.3](https://www.w3.org/TR/speech-grammar/#S4.3): XML DOCTYPE | Recommended | SRGS | 
| Character encoding | Recommended | [4.4](https://www.w3.org/TR/speech-grammar/#S4.4): encoding attribute in XML declaration | Recommended | SRGS | 
| Language | Required in voice mode Ignored in DTMF mode | [4.5](https://www.w3.org/TR/speech-grammar/#S4.5): xml:lang attribute on grammar element | Required in voice mode Ignored in DTMF mode | SRGS | 
| Mode | Optional | [4.6](https://www.w3.org/TR/speech-grammar/#S4.6): mode attribute on grammar element | Optional | SRGS | 
| Root rule | Optional | [4.7](https://www.w3.org/TR/speech-grammar/#S4.7): root attribute on grammar element | Required | SRGS | 
| Tag format | Optional | [4.8](https://www.w3.org/TR/speech-grammar/#S4.8): tag-format attribute on grammar element | String literal and ECMAScript are supported | SRGS, SISR | 
| Base URI | Optional | [4.9](https://www.w3.org/TR/speech-grammar/#S4.9): xml:base attribute on grammar element | Optional | SRGS | 
| Pronunciation lexicon | Optional, multiple allowed | [4.10](https://www.w3.org/TR/speech-grammar/#S4.`0): lexicon element | Not supported | SRGS, PLS | 
| Metadata | Optional, multiple allowed | [4.11.1](https://www.w3.org/TR/speech-grammar/#S4.11.1): meta element | Required | SRGS | 
| XML metadata | Optional, XML only | [4.11.2](https://www.w3.org/TR/speech-grammar/#S4.11.2): metadata element | Optional | SRGS | 
| Tag | Optional, multiple allowed | [4.12](https://www.w3.org/TR/speech-grammar/#S4.12): tag element | Global tags not supported | SRGS | 

**Example**

```
<?xml version="1.0" encoding="ISO-8859-1"?>

<!DOCTYPE grammar PUBLIC "-//W3C//DTD GRAMMAR 1.0//EN"
                  "http://www.w3.org/TR/speech-grammar/grammar.dtd">

<grammar xmlns="http://www.w3.org/2001/06/grammar"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xml:base="http://www.example.com/base-file-path"
         xsi:schemaLocation="http://www.w3.org/2001/06/grammar
                             http://www.w3.org/TR/speech-grammar/grammar.xsd"
         xml:lang="en-US"
         version="1.0"
         mode="voice"
         root="city"
         tag-format="semantics/1.0">
```