---
format: "aidr-story-markdown/v1"
id: "dc33addb89203be2149f73f3b1d69131d503b73708e2604d62aaa0bcd016c16c"
canonical_url: "https://aidr.today/dc33addb?lang=en"
title: "Lessons learned building Fronteira, an MCP proxy with behavioral guardrails"
lang: "en"
requested_lang: "en"
available_langs: ["en","vi"]
translation_fallback: null
fallback_fields: []
published_at: "2026-10-16T12:39:23.000Z"
category: "Tools"
topics: ["safety","devtools"]
source_urls: ["https://wiki.alcidesfonseca.com/blog/lessons-learned-building-fronteira/","https://lobste.rs/s/gtev9y/lessons_learned_building_fronteira_mcp"]
summary: "Fronteira is an MCP proxy that acts as a behavioral firewall, allowing users to log in through the browser and add integrations with GitHub, Gmail and other services through their MCP servers."
---

# Lessons learned building Fronteira, an MCP proxy with behavioral guardrails

> [Open the canonical story](<https://aidr.today/dc33addb?lang=en>)

**Published:** 2026-10-16T12:39:23.000Z
**Category:** Tools
**Topics:** safety, devtools

## Summary

Fronteira is an MCP proxy that acts as a behavioral firewall, allowing users to log in through the browser and add integrations with GitHub, Gmail and other services through their MCP servers\.

## Sources

- [Story source](<https://wiki.alcidesfonseca.com/blog/lessons-learned-building-fronteira/>)
- [Discussion](<https://lobste.rs/s/gtev9y/lessons_learned_building_fronteira_mcp>)