I am building the documentation of custom functions for Google Sheets directly in the Workspace Add-on sidebar so the users have the reference right there where they need it.
I've design it as collapsible sections where the title is the name of the function and a short description and then when you uncollapse you can see the full description, parameters, examples etc. Here is the code:
<pre style='color:#000000;background:#ffffff;'><span style='color:#800000; font-weight:bold; '>function</span> viewFormulas_<span style='color:#808030; '>(</span><span style='color:#808030; '>)</span> <span style='color:#800080; '>{</span>
<span style='color:#800000; font-weight:bold; '>const</span> builder <span style='color:#808030; '>=</span> CardService<span style='color:#808030; '>.</span>newCardBuilder<span style='color:#808030; '>(</span><span style='color:#808030; '>)</span>
<span style='color:#808030; '>.</span>setName<span style='color:#808030; '>(</span><span style='color:#800000; '>'</span><span style='color:#0000e6; '>Fórmulas</span><span style='color:#800000; '>'</span><span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>
<span style='color:#800000; font-weight:bold; '>const</span> section <span style='color:#808030; '>=</span> CardService<span style='color:#808030; '>.</span>newCardSection<span style='color:#808030; '>(</span><span style='color:#808030; '>)</span>
<span style='color:#808030; '>.</span>setHeader<span style='color:#808030; '>(</span><span style='color:#800000; '>'</span><span style='color:#0000e6; '>Fórmulas disponibles (beta)</span><span style='color:#800000; '>'</span><span style='color:#808030; '>)</span>
<span style='color:#808030; '>.</span>setCollapsible<span style='color:#808030; '>(</span><span style='color:#0f4d75; '>false</span><span style='color:#808030; '>)</span>
<span style='color:#808030; '>.</span>setNumUncollapsibleWidgets<span style='color:#808030; '>(</span><span style='color:#008c00; '>0</span><span style='color:#808030; '>)</span>
<span style='color:#808030; '>.</span>addWidget<span style='color:#808030; '>(</span>CardService<span style='color:#808030; '>.</span>newTextParagraph<span style='color:#808030; '>(</span><span style='color:#808030; '>)</span>
<span style='color:#808030; '>.</span>setText<span style='color:#808030; '>(</span><span style='color:#800000; '>'</span><span style='color:#0000e6; '>Puedes ver las fórmulas y sus parámetros directo sobre una celda escribiendo <b>=JAGUAR_</b>. Adicionalmente aquí listamos todas con ejemplos adicionales.</span><span style='color:#800000; '>'</span><span style='color:#808030; '>)</span>
<span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>
builder<span style='color:#808030; '>.</span>addSection<span style='color:#808030; '>(</span>section<span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>
FORMULAS<span style='color:#808030; '>.</span><span style='color:#800000; font-weight:bold; '>forEach</span><span style='color:#808030; '>(</span><span style='color:#808030; '>(</span>formula<span style='color:#808030; '>)</span> <span style='color:#808030; '>=</span><span style='color:#808030; '>></span> <span style='color:#800080; '>{</span>
<span style='color:#800000; font-weight:bold; '>const</span> section <span style='color:#808030; '>=</span> CardService<span style='color:#808030; '>.</span>newCardSection<span style='color:#808030; '>(</span><span style='color:#808030; '>)</span>
<span style='color:#808030; '>.</span>setHeader<span style='color:#808030; '>(</span><span style='color:#800000; '>`</span><span style='color:#800000; '>${</span><span style='color:#797997; '>formula</span><span style='color:#808030; '>.</span><span style='color:#797997; '>name</span><span style='color:#800000; '>}</span><span style='color:#0f69ff; '>\n</span><span style='color:#800000; '>${</span><span style='color:#797997; '>formula</span><span style='color:#808030; '>.</span><span style='color:#797997; '>shortDescription</span><span style='color:#800000; '>}</span><span style='color:#800000; '>`</span><span style='color:#808030; '>)</span>
<span style='color:#808030; '>.</span>setCollapsible<span style='color:#808030; '>(</span><span style='color:#0f4d75; '>true</span><span style='color:#808030; '>)</span>
<span style='color:#808030; '>.</span>setNumUncollapsibleWidgets<span style='color:#808030; '>(</span><span style='color:#008c00; '>0</span><span style='color:#808030; '>)</span>
<span style='color:#808030; '>.</span>addWidget<span style='color:#808030; '>(</span>CardService<span style='color:#808030; '>.</span>newTextParagraph<span style='color:#808030; '>(</span><span style='color:#808030; '>)</span>
<span style='color:#808030; '>.</span>setText<span style='color:#808030; '>(</span><span style='color:#800000; '>`</span><span style='color:#0000e6; '><b>Descripción:</b></span><span style='color:#0f69ff; '>\n</span><span style='color:#800000; '>${</span><span style='color:#797997; '>formula</span><span style='color:#808030; '>.</span><span style='color:#797997; '>description</span><span style='color:#800000; '>}</span><span style='color:#800000; '>`</span><span style='color:#808030; '>)</span>
<span style='color:#808030; '>)</span>
<span style='color:#808030; '>.</span>addWidget<span style='color:#808030; '>(</span>CardService<span style='color:#808030; '>.</span>newTextParagraph<span style='color:#808030; '>(</span><span style='color:#808030; '>)</span>
<span style='color:#808030; '>.</span>setText<span style='color:#808030; '>(</span><span style='color:#800000; '>`</span><span style='color:#0000e6; '><b>Sintaxis:</b></span><span style='color:#0f69ff; '>\n</span><span style='color:#800000; '>${</span><span style='color:#797997; '>formula</span><span style='color:#808030; '>.</span><span style='color:#797997; '>syntax</span><span style='color:#800000; '>}</span><span style='color:#800000; '>`</span><span style='color:#808030; '>)</span>
<span style='color:#808030; '>)</span>
formula<span style='color:#808030; '>.</span>parameters<span style='color:#808030; '>.</span><span style='color:#800000; font-weight:bold; '>forEach</span><span style='color:#808030; '>(</span><span style='color:#808030; '>(</span>param<span style='color:#808030; '>)</span> <span style='color:#808030; '>=</span><span style='color:#808030; '>></span> <span style='color:#800080; '>{</span>
section<span style='color:#808030; '>.</span>addWidget<span style='color:#808030; '>(</span>CardService<span style='color:#808030; '>.</span>newTextParagraph<span style='color:#808030; '>(</span><span style='color:#808030; '>)</span>
<span style='color:#808030; '>.</span>setText<span style='color:#808030; '>(</span><span style='color:#800000; '>`</span><span style='color:#0000e6; '><b></span><span style='color:#800000; '>${</span><span style='color:#797997; '>param</span><span style='color:#808030; '>.</span><span style='color:#797997; '>name</span><span style='color:#800000; '>}</span><span style='color:#0000e6; '> - </span><span style='color:#800000; '>${</span><span style='color:#797997; '>param</span><span style='color:#808030; '>.</span><span style='color:#797997; '>condition</span><span style='color:#800000; '>}</span><span style='color:#0000e6; '></b></span><span style='color:#0f69ff; '>\n</span><span style='color:#800000; '>${</span><span style='color:#797997; '>param</span><span style='color:#808030; '>.</span><span style='color:#797997; '>description</span><span style='color:#800000; '>}</span><span style='color:#800000; '>`</span><span style='color:#808030; '>)</span>
<span style='color:#808030; '>)</span>
<span style='color:#800080; '>}</span><span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>
section<span style='color:#808030; '>.</span>addWidget<span style='color:#808030; '>(</span>CardService<span style='color:#808030; '>.</span>newTextParagraph<span style='color:#808030; '>(</span><span style='color:#808030; '>)</span>
<span style='color:#808030; '>.</span>setText<span style='color:#808030; '>(</span><span style='color:#800000; '>`</span><span style='color:#0000e6; '><b>Ejemplos:</b></span><span style='color:#0f69ff; '>\n</span><span style='color:#800000; '>${</span><span style='color:#797997; '>formula</span><span style='color:#808030; '>.</span><span style='color:#797997; '>examplesDescription</span><span style='color:#800000; '>}</span><span style='color:#800000; '>`</span><span style='color:#808030; '>)</span>
<span style='color:#808030; '>)</span>
formula<span style='color:#808030; '>.</span>examples<span style='color:#808030; '>.</span><span style='color:#800000; font-weight:bold; '>forEach</span><span style='color:#808030; '>(</span><span style='color:#808030; '>(</span>example<span style='color:#808030; '>)</span> <span style='color:#808030; '>=</span><span style='color:#808030; '>></span> <span style='color:#800080; '>{</span>
section<span style='color:#808030; '>.</span>addWidget<span style='color:#808030; '>(</span>CardService<span style='color:#808030; '>.</span>newTextParagraph<span style='color:#808030; '>(</span><span style='color:#808030; '>)</span>
<span style='color:#808030; '>.</span>setText<span style='color:#808030; '>(</span><span style='color:#800000; '>`</span><span style='color:#0000e6; '><b>=</span><span style='color:#800000; '>${</span><span style='color:#797997; '>example</span><span style='color:#808030; '>.</span><span style='color:#797997; '>func</span><span style='color:#800000; '>}</span><span style='color:#0000e6; '></b></span><span style='color:#0f69ff; '>\n</span><span style='color:#800000; '>${</span><span style='color:#797997; '>example</span><span style='color:#808030; '>.</span><span style='color:#797997; '>description</span><span style='color:#800000; '>}</span><span style='color:#800000; '>`</span><span style='color:#808030; '>)</span>
<span style='color:#808030; '>)</span>
<span style='color:#800080; '>}</span><span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>
builder<span style='color:#808030; '>.</span>addSection<span style='color:#808030; '>(</span>section<span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>
<span style='color:#800080; '>}</span><span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>
<span style='color:#800000; font-weight:bold; '>return</span> builder<span style='color:#808030; '>.</span>build<span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>
<span style='color:#800080; '>}</span>
</pre>
<!--Created using ToHtml.com on 2021-04-23 12:52:48 UTC -->
I don't think it is even worth submitting an issue in the bug tracker but just as a FYI.