Thomas Claburn
Our Take: Mozilla is right to flag real risks with Google’s Prompt API: it bundles a vendor-specific model and policy into a browser API, which can push developers to change the way they build.
Your Takeaway: There is a very real risk for everyone of AI being built in by the back door even if a product doesn’t appear to use AI. Due diligence in software is getting very difficult.
Treat any browser‑provided AI API as a potential vector for vendor lock‑in and unexpected content controls; push for neutral, implementable standards that separate API mechanics from any single model or provider policy, test real performance and harms before adoption, and avoid building critical product flows that depend on Chrome‑specific AI behaviour.
Mozilla opposes Google’s new Prompt API because it may limit web openness and favor Google’s AI model. They worry it forces developers to follow Google’s rules, hurting fairness and interoperability. Google says the API encourages innovation, but tests show its AI often performs poorly.
Highlights
"The core problem is interoperability," he said. "Prompts are tightly coupled to models; developers will inevitably tune to the quirks and policies of whatever model they’re building against.
"This seems like a bad direction for an API on the web platform, and sets a worrying precedent for more APIs that have [browser]-specific rules around usage," he said.
Perhaps more significantly, Archibald notes that using the Prompt API requires agreeing to Google’s Generative AI Prohibited Uses Policy, which prohibits activities that are not necessarily illegal, like generating "disturbing" content.
First, he worries that Google’s own Nano model will become the default and that developers will standardize on it in an effort to make the non-deterministic responses of an AI model more predictable. That tendency, he argues, will create pressure for Apple and Mozilla to license Nano, for the sake of a common user experience.
Mozilla’s concern, as articulated by Archibald, has to do with what the Prompt API means for the web, not to mention Google’s justification for deployment.
Various vendors like OpenAI and Perplexity have shipped browsers that embed access to remotely hosted AI models. Mozilla itself is testing an AI-based Smart Window in Firefox and it’s developing tools for AI model scaffolding.
The Prompt API, as Google describes it, "gives web pages the ability to directly prompt a browser-provided language model." It provides a way to send natural language instructions to Google’s Gemini Nano model, which is small enough to be downloaded for local inference through Chrome.
"We continue to oppose this API, and feel it has severe negative consequences to the interoperability, updatability, and neutrality of the web platform," said Archibald.
Jake Archibald, Mozilla web developer relations lead, articulated the org’s concerns in a GitHub discussion of the API, which provides a standard way to send and receive prompts and responses from a local machine learning model.