# MCP Colors: Systematically deal with prompt injection risk

DevFeed: [MCP Colors: Systematically deal with prompt injection risk](<https://devfeed.tech/articles/mcp-colors-systematically-deal-with-prompt-injection-risk-33479.md>)

Original publisher: [Read original article](<https://timkellogg.me/blog/2025/11/03/colors>)

Published: 2025-11-03T00:00:00Z

Content type: article

Language: en

Sources: [Tim Kellogg](<https://devfeed.tech/sources/tim-kellogg.md>)

Topics: [MCP](<https://devfeed.tech/topics/mcp.md>), [prompt injection](<https://devfeed.tech/topics/prompt-injection.md>), [Security](<https://devfeed.tech/topics/security.md>)

Tags: [agent](<https://devfeed.tech/tags/agent.md>), [mcp](<https://devfeed.tech/tags/mcp.md>), [prompt-injection](<https://devfeed.tech/tags/prompt-injection.md>), [security](<https://devfeed.tech/tags/security.md>), [tool](<https://devfeed.tech/tags/tool.md>)

## AI overview

The article proposes labeling MCP tools and data inputs with "colors" to help agents identify unsafe combinations involving private data, prompt injection, and critical actions. It recommends systematically labeling tools and resources, potentially using an LLM to assist with the classification, so agents can detect unsafe states at runtime or earlier.

## Source excerpt

Prompt injection is annoying enough that most (all??) apps so far are mostly just ignoring that it exists and hoping a solution will come along before their customer base grows enough to actually care about security. There are answers!