126 million tokens. Consumed in 7 hours. Zero messages sent.
That's what one Claude user reported after opening their Anthropic dashboard to find a massive drawdown with no conversation history to explain it. The post immediately drew responses from other users who had noticed similar silent consumption.
The most likely culprits are background integrations. Claude Code, IDE extensions, and MCP (Model Context Protocol) servers - which let Claude connect to external tools and data sources you configure - all make API calls without you actively typing anything. Claude Code in particular can run background processes for file indexing, context maintenance, and automated hooks that tick along even when you're not at your desk.
For developers paying per token via Anthropic's API, this is a direct billing problem. At current pricing, 126 million tokens on Claude Sonnet could translate to anywhere from a few hundred to over a thousand dollars depending on whether they're input or output tokens. For Max plan subscribers, the same behavior burns through monthly allocations meant for actual work.
What to check if your numbers look off: pull up your Anthropic dashboard and look for usage broken down by API key - that narrows down which application is responsible. Check whether Claude Code or any IDE extension is running in the background on your machine. Review any MCP server configurations you've set up and whether they're polling on a schedule.
Anthropichasn't publicly addressed the reports, and there's no indication this is a billing error - the tokens appear to have been genuinely consumed by connected applications. The practical takeaway: audit what has access to your API key, the same way you'd audit OAuth grants on any cloud account, and set up usage alerts so a runaway background process doesn't quietly drain your quota overnight.