Harmonic Security
Governs how employees and AI agents use AI tools, classifying each interaction with small language models and stopping sensitive data from leaking without banning AI outright.
About Harmonic Security
Harmonic Security, headquartered in San Francisco and London, watches AI use across browsers, desktop apps, command-line tools, IDEs, AI APIs and MCP-based agent workflows.
Its proprietary small language models judge the business meaning of each interaction within milliseconds, so a developer describing a schema is treated differently from someone pasting live credentials.
Responses range from silent logging to warnings, coaching and real-time blocking, set by tool, account, data, user and action.
It rolls out through endpoint management tools such as Intune and Jamf, with a browser extension and an MCP gateway for Windows, macOS and Linux.
The company says its software is used by millions of employees at more than 100 companies.
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