A-TIER technique
Build-your-own CLI for agents — control apps that lack an MCP
100k ft — What is this?
Build-your-own CLI for agents — control apps that lack an MCP
50k ft — Why care?
When a program has no MCP server or the MCP misses controls you need, tell the agent 'Build yourself a CLI tool to interact with [program]', even down to every button of a DAW. MCP stays best for auth, discovery and distribution; a custom CLI wins for bespoke complex workflows and uses fewer tokens. Expect security flags.
10k ft — Key takeaways
• CLIs keep context lean versus large MCP tool schemas.
• Prompt: 'Build yourself a CLI tool to interact with X.'
• Use MCP for shared, authenticated integrations; CLI for custom deep control.
5k ft — Tools & techniques
(no tools tagged)
AI agents, MCP, MCP server, agent-built CLI tools
1k ft — Deep-dive / try it
Copy this ➡️ “Build yourself a CLI tool to interact with [x program].”
You can use this trick when the tool you want your agent to use doesn’t have an MCP or the MCP doesn’t support the controls you want.
Some caveats:
1. MCP is still the most robust option. It solves for authentication, discovery, and distribution. It creates a consistent experience for agents interacting with a platform.
2. CLI is great for specific, custom, more complex workflows. It uses fewer tokens as well.
Featuring @parthintelligence
📍 @catlabs
Transcript excerpt
If there's no MCP, or if there's no official connector, you can just tell the agent, build yourself a CLI tool to interact with this tool, and you can ask for things that the MCP doesn't support, and then you go further. So in this case, I'm like, dude, just connect to everything, every single button. I should be able to describe the change, and you should be able to control the entire DAW, because I have no, I don't have that kind of experience. And so it just- Does it ever give you security pushback? Actually, I got flagged for cyber risk.
Appears in
- Guide: Every App Is Headless Now — agents that build their own control surface
- Deeper dive: Every App Is Headless Now — agents that build their own control surface
- Guide: Scan, Fit, Print — agents that design parts around real objects
- Deeper dive: Scan, Fit, Print — agents that design parts around real objects