Last updated: August 15, 2026

Clevystar — Vocabulary Helper is a local-first browser extension. It does not include analytics, advertising, telemetry, user accounts, or developer-operated servers.


The extension stores the following information in the user's local Firefox or Zen Browser profile using browser.storage.local:

• vocabulary entries the user chooses to save;
• definitions, examples, phonetics, synonyms, antonyms, related words, collocations, audio URLs, and source/license metadata associated with those entries;
• local timestamps and organizational fields used by the vocabulary list; and
• a limited cache of up to 250 previously requested dictionary results for offline resilience.

Clevystar does not transmit the locally saved vocabulary collection to external services. Users can delete individual words, delete all saved vocabulary, clear the lookup cache, or uninstall the extension. Uninstalling normally removes the extension's local storage from the browser profile.


Network transmission happens only when the user explicitly selects a word and activates the inline Clevystar lookup button or Explain selected word, or plays pronunciation audio:

1. The selected word is sent over HTTPS to Free Dictionary API (api.dictionaryapi.dev) to request dictionary information.
2. The selected word is sent over HTTPS to EnglishDictionaryAPI (englishdictionaryapi.com) to request enrichment data such as pronunciation audio, antonyms, related words, and fallback dictionary information.
3. For an all-uppercase initialism such as FAA, the exact-cased selected word is sent over HTTPS to English Wiktionary (en.wiktionary.org) to avoid confusing it with a lowercase dictionary entry.
4. The selected word is sent over HTTPS to Datamuse (api.datamuse.com) to request contextual collocation suggestions.
5. When the user presses Pronounce and remote audio is available, it is streamed from the HTTPS URL returned by a dictionary service. Audio bytes are not bundled, downloaded as an export, or retained by the extension. If remote audio is unavailable or fails, the extension asks the browser's speech-synthesis feature to pronounce the word.

The extension does not send the page URL, browsing history, complete page contents, saved vocabulary collection, exports, persistent identifiers, cookies, or analytics data to these services. The external services process requests under their own privacy practices and infrastructure policies.


JSON, CSV, Anki TSV, and Quizlet TSV files are generated locally and downloaded only after a user action. Imported files are read locally by the extension. The extension does not upload imports or exports.

Exported files may contain dictionary data, user notes, source metadata, or page information if those fields are present in saved entries. Audio URLs and audio-provider metadata are intentionally excluded from every export format. Users should inspect exports before sharing them.

• menus creates the selected-text context-menu command.
• storage stores vocabulary and cached results locally.
• website access allows the extension to inspect the selected word and display the result card.
• access to api.dictionaryapi.dev, englishdictionaryapi.com, en.wiktionary.org, and api.datamuse.com allows user-initiated lookup requests.

Firefox classifies the selected word as websiteContent because it is text visible on a webpage. The manifest declares this as required transmitted data because dictionary lookup cannot work without sending that word to the lookup services.


Material changes to data handling will be documented in this policy and the extension changelog.
Have questions or concerns about this privacy policy? Contact the maintainer at hello@nazariistudio.com