AI tool comparison
CrabTrap vs TUI-use
Which one should you ship with? Here is the side-by-side panel verdict, pricing read, reviewer split, and community vote comparison.
Developer Tools
CrabTrap
Open-source HTTP proxy that enforces security policies on AI agent API calls
50%
Panel ship
—
Community
Paid
Entry
CrabTrap is an open-source HTTP/HTTPS proxy built by Brex's engineering team that sits between AI agents and the external internet, evaluating every outbound request against configurable security policies before it reaches any third-party API. It uses a two-tier evaluation system: fast deterministic static rules handle the obvious cases (block this domain, require this header), while an LLM-as-a-judge handles ambiguous requests that need semantic understanding — like determining whether a request to send an email is within scope of the current task. Built in Go with a TypeScript frontend, CrabTrap ships with a PostgreSQL-backed audit log and a web UI for policy management. It supports MITM inspection of HTTPS traffic, request/response logging, and policy versioning — making it suitable for production agentic systems where compliance or security teams need a paper trail. Version 0.0.1 was released April 17, 2026 and is MIT licensed. The problem it solves is real: as AI agents gain more autonomy and access to external APIs, the attack surface grows. A compromised or misbehaving agent that can freely call any URL is a significant risk. CrabTrap gives engineering teams a single chokepoint to enforce least-privilege access — something that's been missing from most agentic frameworks that assume a trusted execution environment.
Developer Tools
TUI-use
Let AI agents take control of interactive terminal programs
75%
Panel ship
—
Community
Paid
Entry
TUI-use is an open-source library that gives AI agents the ability to interact with traditional interactive terminal (TUI) applications — think vim, htop, ssh sessions, database CLIs, and legacy text-based UIs that were never designed for programmatic control. Instead of requiring a GUI or a REST API, TUI-use interprets terminal output as structured state and sends synthetic keystrokes back, enabling agents to "see" and "drive" any TUI application as if they were a human at a keyboard. The project was born from a real pain point: AI coding agents can call bash commands and write files, but they fail badly the moment a tool opens an interactive prompt waiting for user input. TUI-use solves this by building a state machine layer over PTY (pseudo-terminal) interfaces, letting agents read the current screen buffer, detect interactive prompts, and respond intelligently. It ships with adapters for common TUI patterns and a clean API that works with any LLM tool-use framework. The Show HN post attracted genuine interest from the ops and DevOps community — many existing workflows depend on tools that expose only an interactive terminal interface. TUI-use fills a real gap in the "AI agents that control computers" space by handling the long tail of CLI programs that have no API, no GUI, and no intention of ever getting one.
Reviewer scorecard
“This fills a gap that every production agentic system needs but almost no one has solved yet. The two-tier policy engine — static rules for speed, LLM for ambiguity — is the right architecture. The fact that Brex built and open-sourced this suggests they've already battle-tested it against real agent deployments.”
“This is the missing piece for automating legacy ops workflows. Half my toolchain is interactive TUI apps that choke every agent pipeline — TUI-use just quietly solves that. The PTY state machine approach is clever and the API is clean.”
“v0.0.1 with 126 GitHub stars is a weekend project right now, not infrastructure you should bet your production agents on. The LLM-as-a-judge for policy evaluation is also expensive and introduces its own latency — you're adding an AI call to evaluate every AI agent call. The operational complexity of running MITM HTTPS inspection in production is non-trivial.”
“Screen-scraping terminal output to infer state is fragile — any change in terminal colors, locale, or version will break your parser. This works fine for demos but I'd want to see battle-hardened error recovery before running it against anything production-critical.”
“Agent security tooling is where network security tooling was in the early 2000s — primitive, fragmented, and urgently needed. CrabTrap is an early bet on a category that will be worth billions once enterprises start mandating audit trails for agentic systems. Brex building this in-house and open-sourcing it is a strong signal of what production agent operators actually need.”
“The real unlock here is making 40 years of terminal software suddenly agentic without a single line change from the original developers. TUI-use could quietly become the bridge that lets AI agents inherit the entire unix toolchain ecosystem.”
“This is deeply in the DevOps/infrastructure lane — not something a creator or designer would ever touch directly. But if the tools you use to generate content are backed by CrabTrap-style security, you'd want that. For now, it's a ship for the engineers who configure your AI stack, a skip for everyone else.”
“Not my usual domain but I can see this saving hours for anyone managing servers — having an agent that can actually ssh in and navigate interactive prompts without getting stuck is genuinely useful. The demo videos make it look surprisingly smooth.”
Weekly AI Tool Verdicts
Get the next comparison in your inbox
New AI tools ship daily. We compare them before you waste an afternoon.