Custos — The bouncer for your AI agents vs Watchdog
Comprehensive feature analysis, ratings breakdown, platform compatibility, and community review comparison.
Custos — The bouncer for your AI agents
Stop AI agents from doing things they shouldn't.
Detailed Feature Comparison Matrix
Compare Other Tools| Dimension | Custos — The bouncer for your AI agents |  Watchdog |
|---|---|---|
| Primary Category | Developer Tools | Developer Tools |
| Community Rating | No ratings(0 reviews) | No ratings(0 reviews) |
| Community Upvotes | 7 votes | 10 votes |
| Supported Platforms | Web | Web |
| Tags & Focus | #Artificial Intelligence#Developer Tools#GitHub#Security | #Artificial Intelligence#Developer Tools#GitHub#Tech |
| Maker / Company | Independent Developer | Independent Developer |
| Platform Verification | Community Listing | Community Listing |
About Custos — The bouncer for your AI agents
Custos is an open-source safety and control layer designed specifically for AI agents, acting as a reliable 'bouncer' for your applications. As AI agents increasingly interact with critical infrastructure, Custos sits directly between the agent and its tools—such as APIs, files, databases, shell commands, and MCP servers—to intercept and verify every single action before it is executed.
Built for teams deploying AI agents in real-world environments, Custos allows you to explicitly define rule sets determining what an agent is allowed to do, automatically blocking anything outside of those bounds. Furthermore, every action attempted or performed is recorded in a secure, tamper-evident audit trail. With native support for both Python and TypeScript, Custos provides developers with the robust security infrastructure needed to prevent AI agents from performing unintended or harmful actions.
Pros of Custos — The bouncer for your AI agents
- Acts as an interception layer between AI agents and critical tools like APIs, files, databases, shell commands, and MCP servers.
- Provides a tamper-evident audit trail recording every agent action.
- Open-source software built for teams running real-world AI agent environments.
- Supports both Python and TypeScript development stacks.
Cons of Custos — The bouncer for your AI agents
- Relies entirely on developer-defined rules to catch unexpected agent behaviors.
- Limited to Python and TypeScript language support based on current specifications.
- Requires integration work to sit between existing agents and their target tools.
Frequently Asked Questions
What is Custos?
Custos is an open-source safety and control layer for AI agents that sits between the agent and its tools to check every action before it runs, blocking anything outside of defined rules.
Which programming languages are supported?
Custos works with both Python and TypeScript.
How does Custos handle security and tracking?
Custos checks actions against your defined rules and records every action in a tamper-evident audit trail.
What tools can Custos monitor and control?
Custos can monitor actions directed at APIs, files, databases, shell commands, and MCP servers.
About Watchdog
Watchdog is a dedicated local control plane designed specifically for developers managing subagents, agentic loops, and complex agent execution graphs. While parallel coding agents enable rapid development, coordinating concurrent tasks can quickly become complex and difficult to track. Watchdog solves this issue by offering a centralized, real-time dashboard of your entire agent network.
Rather than acting as a passive monitoring dashboard, Watchdog operates as an active control room. From a single workspace, developers can observe what each agent is working on, track real-time token consumption and costs, identify the specific model and reasoning effort in use, and map agent relationships. Crucially, Watchdog allows you to actively stop, steer, and control your running agents in real time.
To fit seamlessly into different developer environments and workflow preferences, Watchdog provides three distinct user interfaces:
- Yard: A unique, pixel-art-themed user interface.
- Operator: A dedicated, streamlined control interface.
- TUI: A Terminal User Interface tailored specifically for command-line environments.
Pros of Watchdog
- Provides a unified, real-time control plane to actively stop, steer, and manage all subagents
- Tracks critical execution metrics including token consumption, costs, and reasoning efforts
- Offers three flexible user surfaces: Yard (pixel art UI), Operator, and a terminal-based TUI
- Maps and visualizes complex relationships between parallel execution graphs and agentic loops
Cons of Watchdog
- Operates as a local control plane, which may not suit teams looking for a fully managed SaaS cloud solution
- Primarily tailored for coding-centric agents and execution graphs rather than general-purpose business automations
Frequently Asked Questions
What is Watchdog?
Watchdog is a local control plane designed to help developers manage, monitor, and actively direct subagents, agentic loops, and execution graphs from a single, unified view.
What are the three UI surfaces available in Watchdog?
Watchdog offers three user surfaces to match your preferred workflow: Yard (a unique pixel art UI), Operator (a dedicated, streamlined control interface), and a Terminal User Interface (TUI) for command-line environments.
Does Watchdog allow you to control agents, or is it read-only?
Watchdog is an active control room. It goes beyond simple passive monitoring, allowing you to actively stop, steer, and control all of your agents from a single workspace.
What details can I track for each agent using Watchdog?
You can monitor what each agent is currently working on, the specific model and reasoning effort being utilized, real-time token consumption, associated execution costs, and the relationships between different agents in your execution graph.