AI tool comparison
Euphony 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
Euphony
Turn Codex CLI sessions and Harmony JSON into browsable conversation timelines
50%
Panel ship
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Community
Free
Entry
Euphony is an open-source, browser-based visualization tool from OpenAI that transforms raw Harmony JSON/JSONL chat data and Codex CLI session logs into interactive, filterable timelines. Paste JSON, upload a file, or point it at a public URL — Euphony auto-detects the format and renders a structured conversation view. The tool surfaces conversation-level and message-level metadata through a dedicated inspection panel, supports JMESPath-based filtering for querying large datasets, includes translation support, and can run entirely in the browser without any server dependency. For developers debugging Codex agent runs or analyzing large conversation datasets, it replaces manual JSON parsing. Euphony ships as a web component library so it can be embedded in other tools, and includes a FastAPI backend mode for remote loading and Harmony rendering. It's MIT licensed and available on GitHub at openai/euphony.
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
“Debugging Codex agent sessions used to mean manually reading JSON in a text editor. Euphony is what that developer experience should have always been — structured timelines, metadata inspection, and JMESPath filtering that actually works on large session files.”
“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.”
“This is purpose-built for OpenAI's Harmony format and Codex sessions, which means it's primarily useful if you're already deep in the OpenAI ecosystem. Developers using other agent frameworks get limited value here unless they adapt the format.”
“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.”
“Observability tooling for AI agents is a nascent but critical category. Euphony is a first step toward treating agent session logs with the same rigor we apply to application traces and logs — we'll see a whole category of tools like this emerge over the next two years.”
“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.”
“This is deep dev tooling with a specific niche — valuable for AI engineers but not directly applicable to creative workflows. The visualization quality is clean, but most creators won't interact with raw Harmony JSON.”
“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.”
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