Tools that do not call a model
Citation formatter and Model comparison explorer run from the fields or the list you already have. They do not send your text to a model host. The citation formatter only rearranges author, title, year, container, and URL. The comparison explorer only filters pages Keplar has already published. It has no score and no ranking.
Tools that call one free model
Prompt optimizer, Study guide generator, Flashcard generator, Research question generator, Presentation outline generator, Text summarizer, Writing improvement tool, Learning plan generator each send your text to one model whose slug ends in :free and whose listed price is zero. The server picks that model. The page does not let you choose a paid model. If no free model is in the catalog, or the server has no key for it, the tool says it is unavailable. It does not invent a paragraph to fill the box.
Free model hosts may log what you paste. The form says so. Do not paste passwords, keys, or someone else's private notes.
The caps
Each address can run a model tool 8 times in 60 minutes. The text you submit is capped at 4,000 characters. The reply is capped at 500 tokens. Those numbers are the constants in the tool module, not a traffic estimate.
If the host's usage report includes a cost above zero, the reply is thrown away and you see an error. A free tool is not allowed to spend money to finish a sentence.
What these tools are not
They are not Study mode, not a PowerPoint export, and not Deep Research. Study mode, slides, and web research live in the signed-in product and follow that product's plan. A free outline is a list of headings. It is not a deck. A free summary is one model's draft. It is not a Keplar answer that compared several models and showed where they split.
Use the tool page for the form. Use Ask when you want that comparison. Use the docs for the feature that matches the job, such as sources and citations, Study mode, or slides.