Claude Usage Tracker by lugia19

This extension helps you monitor how much of your Claude usage quota remains. It calculates token consumption from various sources including uploaded files, project knowledge, chat history, and AI responses.

Most elements in the chat UI (Namely the length, cost, estimate, caching status) have a tooltip explaining them further! Be sure to check them out.

The extension tracks token usage from:
- Files - Documents uploaded to chats or synced via Google Drive, Github, etc
- Projects - Knowledge files and custom instructions
- Personal preferences - Your configured settings
- Message history - Full conversation context
- System prompts - Enabled tools (analysis, artifacts) on a per-chat basis
- MOST MCPs/Integrations - There are some limitations in cases where a "Knowledge" object is returned that I can't access, such as with web search

Limitations:
- Web search results - The full results are not exposed in the conversation history, so I can't track them properly (See above, Knowledge objects)
- Research - Most of it happens on the backend, so I can't track it at all

Token calculation is handled either through Anthropic's API (if you provide your key) or via gpt-tokenizer.

It will additionally fetch your organization ID on claude.ai to synchronize your usage amounts across devices via firebase, as well as to store data on the amount of tokens you consumed before hitting the usage cap (to crowdsource more accurate counts).

The source code can be found here: https://github.com/lugia19/Claude-Usage-Extension

About the required permissions:
Host Permissions:
- Claude.ai: Needed to read the tokens and usage amounts.
- Github: Needed to fetch the up to date usage caps and settings from the repo.

Actual permissions:
- Tabs: To send updates from the background script to the content scripts
- Storage: To store and track usage amounts
- Alarms: To periodically sync with firebase, and check for the cap reset
- Cookies: To get the sessionKey required to fetch conversation content (This is never stored, not even locally, just used temporarily - blame MV3 for this being required)
- webRequest: To detect when a new message is sent, or data recieved
- notifications: To notify you when your usage has been re-filled

Source code here: https://github.com/lugia19/Claude-Usage-Extension