AI tool comparison
Chrome Prompt API vs Kampala
Which one should you ship with? Here is the side-by-side panel verdict, pricing read, reviewer split, and community vote comparison.
Developer Tools
Chrome Prompt API
Run Gemini Nano inside Chrome — on-device AI inference with no cloud round-trip
75%
Panel ship
—
Community
Free
Entry
Chrome's Prompt API lets web developers call Gemini Nano — Google's compact, locally-running language model — directly from JavaScript, without any server requests after the initial model download. The API accepts text, audio (AudioBuffer or Blob), and visual inputs (images, canvas elements, video frames), returns streaming text responses, and supports JSON Schema-constrained structured output for reliable data extraction. Sessions are created via LanguageModel.create(), with each session maintaining a token-aware context window that prunes older messages automatically while preserving system prompts. The Prompt API complements other Chrome AI primitives including the Summarizer, Writer, Rewriter, Translator, and Language Detector APIs — all running fully on-device. Model requires 22GB+ free disk space for the initial download; subsequent use works offline. This is a meaningful shift for web AI. Developers can now build privacy-preserving AI features — local transcription, smart autocomplete, content classification, on-page summarization — without touching a cloud API or paying per-token costs. Currently supports English, Japanese, and Spanish. Available via Chrome's Origin Trial program with broader rollout expected through 2026.
Developer Tools
Kampala
MITM proxy that reverse-engineers any app into a stable, callable API
75%
Panel ship
—
Community
Free
Entry
Kampala, built by Zatanna AI (YC W26), is a macOS proxy tool that sits between your applications and the internet, intercepts every HTTP/HTTPS request, and automatically reverse-engineers the underlying API. It traces authentication chains — tracking tokens, cookies, and session state — and replays flows on demand, preserving original TLS fingerprints so services can't distinguish API calls from the real app. The key insight is that almost every app that lacks a public API still has a private one — and it's usually more stable than the UI. Kampala targets automation engineers, QA teams, and AI agent builders who need reliable machine-readable access to apps that haven't opened their APIs. Setup is a local MITM cert install; no cloud proxy involved. Currently macOS-only with a Windows waitlist. The team emerged from YC's Winter 2026 batch with backing from Y Combinator. Pricing is in early access, with a free tier planned for solo developers and paid plans for teams building production automations.
Reviewer scorecard
“The JSON Schema structured output is the feature I've been waiting for — finally you can extract clean data from user-typed text without a backend. The 22GB download is a real onboarding hurdle, but once the model is cached, the latency is basically zero compared to cloud APIs. This changes the math for privacy-sensitive consumer apps.”
“This is the tool I've been building in-house at three different companies and never had time to productize properly. The auth chain tracing alone — tracking token refresh flows and session state automatically — would have saved me hundreds of hours. If it works as advertised, it's an instant ship for anyone doing integration work.”
“A 22GB model download as a prerequisite for a web feature is going to have terrible adoption outside of developer demos. Most users won't have that space or patience, and the English/Japanese/Spanish-only limitation rules it out for global products. Wait for the model to shrink before betting your product on this.”
“Terms of service violations are a real concern here. Most apps explicitly prohibit automated access through their private APIs, and companies like LinkedIn and Instagram have sued over exactly this pattern. The MITM cert requirement also opens a broad attack surface. Wait for a clearer legal stance before building production systems on this.”
“On-device inference in the browser is the endgame for consumer AI. No API keys, no latency, no data leaving the device — this is what private-by-default AI looks like. The browser becomes the AI runtime, and Google just got there first. The model size issue is a 2026 problem; by 2027 it'll be 2GB.”
“The long-term story here is about AI agents needing reliable access to every app humans use. We can't wait for every SaaS to ship an official API. Tools like Kampala are how AI agents will integrate with the existing software ecosystem for the next five years, until MCP-style universal interfaces catch up.”
“Real-time image and canvas analysis directly in the browser opens up creative tooling that wasn't possible without a backend. Think live design feedback, style detection from reference images, or on-the-fly alt-text generation — all without a cloud API call. The streaming responses make it feel snappy enough for interactive UX.”
“For social media automation and cross-platform content workflows this is a game-changer. Building automations for platforms with limited or expensive APIs has always required fragile browser scraping — having a stable API layer extracted from the real app traffic is a much better foundation.”
Weekly AI Tool Verdicts
Get the next comparison in your inbox
New AI tools ship daily. We compare them before you waste an afternoon.