AI tool comparison
CrabTrap vs farmer
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
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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
farmer
Approve AI agent tool calls from your phone — swipe to allow or deny
75%
Panel ship
—
Community
Paid
Entry
farmer is an npm package that intercepts tool-call permission requests from AI coding agents and routes them to a mobile-friendly dashboard. Instead of watching a terminal scroll as Claude Code or another agent quietly runs shell commands, you get a swipe-card view on your phone where each pending tool call shows the command, its arguments, and the agent's reasoning — and you approve or deny with a swipe. The architecture is deliberately simple: farmer acts as a hook in the agent's tool-call loop, holds execution until you respond, then forwards your decision back. It ships with a Claude Code adapter out of the box and a documented adapter interface for other agents. The mobile UI is a PWA, so there's nothing to install — just navigate to the local server address in Safari or Chrome. For developers running long agentic sessions — overnight refactors, automated test generation, or repo-wide migrations — farmer fills a real gap. Current tools either block the terminal or run with blind trust. farmer offers a middle path: human-in-the-loop control without requiring you to be physically at your machine.
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 solves the exact anxiety of kicking off a Claude Code session and then walking away. The swipe-card mobile UI is well thought out — you can do a quick code review of the pending command right from the notification. The adapter interface is clean enough that I could wire it to my own agents in an afternoon.”
“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.”
“The security model is concerning: you're routing tool-call details through a local WebSocket server that's exposed to your network. Anyone on the same WiFi can potentially see (or intercept) pending commands. There's no auth on the dashboard in v0.1. Fix that before using this on anything sensitive.”
“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.”
“Human-in-the-loop approval is going to become a compliance requirement for agentic AI in enterprise settings. farmer is ahead of the curve — the patterns it's establishing for mobile-first agent oversight will likely influence how official agent SDKs handle permission gating.”
“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.”
“I run AI agents to manage my content pipeline and frequently can't be at my desk. The idea of approving file writes and API calls from my phone while I'm at a coffee shop is exactly what I've wanted. The activity feed is a nice touch for auditing what ran while I was away.”
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