What is an MCP Prompt?
An MCP prompt is a reusable, parameterised prompt template exposed by an MCP server that provides standardised workflows and interaction patterns for AI agents — like templates for common tasks.
WHY IT MATTERS
MCP prompts are the third capability type alongside tools and resources. While tools enable actions and resources provide data, prompts provide templates for common agent interactions — standardising how agents approach recurring tasks.
A prompt might define a workflow like 'deploy to staging' with parameters for the branch, environment, and approval status. The agent fills in the parameters and gets a well-structured prompt optimised for that specific task.
Prompts are particularly useful for complex workflows that require specific sequencing or domain knowledge. Rather than hoping the agent figures out the right approach, prompts encode best practices into reusable templates.
HOW POLICYLAYER USES THIS
Intercept can enforce governance over prompt template usage. YAML policies can restrict which prompt templates an agent is permitted to invoke, and constrain the parameters passed to them. This prevents agents from using workflow templates that exceed their authorised scope — for example, allowing a 'deploy to staging' prompt but denying 'deploy to production'.