Protection Overview

Guard your agent at runtime with Dome Guardrails.

TL;DR: Dome wraps your Agent with configurable Guardrails that intercept every input and output, blocking attacks before they reach your Agent or your users. Configure which Guards run via your registered Vijil Agent, a TOML file, or a Python dict, then choose early-exit (fast) or parallel execution (thorough) mode.

Evaluation catches vulnerabilities you know to test for. But attackers will try things you did not anticipate like new prompt injection techniques, novel encoding tricks, social engineering patterns that emerge after your last evaluation.

Dome is Vijil’s runtime protection system. It intercepts every input and output, applies configurable Guardrails, and blocks attacks before they reach your Agent or your users. When Diamond identifies vulnerabilities you cannot immediately fix, Dome provides defense-in-depth while you remediate.

How Dome Works

Dome wraps your Agent with configurable Guardrails:

Component	Purpose
Guardrail	Pipeline of Guards (input or output)
Guard	Group of Detectors of one type
Detector	Individual detection method

Protection Types

Security Guards

Detect and block adversarial attacks:

Detector	What It Catches
prompt-injection-mbert	Injected instructions in user input
prompt-injection-deberta-v3-base	Advanced injection attempts
encoding-heuristics	Base64, Unicode, and encoding attacks
security-embeddings	Semantic similarity to known attacks

Moderation Guards

Filter harmful and inappropriate content:

Detector	What It Catches
moderation-flashtext	Fast keyword-based toxicity
moderation-deberta	Neural toxicity classification
moderations-oai-api	OpenAI Moderation API
moderation-llamaguard	Llama Guard safety model

Privacy Guards

Prevent exposure of sensitive data:

Detector	What It Catches
privacy-presidio	PII (names, emails, SSN, etc.)
detect-secrets	API keys, passwords, credentials

Quick Start

You can protect your Agents with default Guards. The default configuration includes:

• Input: Prompt injection detection, encoding heuristics, moderation
• Output: Moderation, PII detection

Configuration Sources

Dome accepts configuration from three sources:

Source	How to Use	Best For
Registered Agent	Pull from your Vijil Console Agent definition	Production: keeps configuration in sync with your policy
TOML file	Reference a local .toml file at initialization	Version-controlled configuration in CI/CD
Python dict	Pass a dict at runtime	Dynamic configuration, testing, prototyping

For the full list of configuration options, see Configure Guardrails.

Scan Results

Every scan returns a result object with the following fields:

Field	Type	Description
is_safe	Boolean	True if content passed all Guards
flagged	Boolean	True if any Guard flagged the content
response_string	String	Original content if safe; fallback message if blocked
exec_time	Float	Scan duration in milliseconds
trace	Dict	Per-Guard and per-Detector execution details

Framework Integrations

Dome integrates with popular agent frameworks. Each guide shows both content-Guard protection and, where available, the full Trust Runtime.

Google ADK

LangChain

LangGraph

Strands

MCP Servers

Performance Options

Mode	Behavior	Best For
Early exit (default)	Stops after the first Guard flags content	Rejecting clearly malicious input with minimal latency
Complete execution	Runs all Guards regardless of flags	Comprehensive audit trails, maximum detection coverage
Parallel execution	Runs Guards concurrently	High-throughput production environments

See Configure Guardrails for the configuration options for each mode.

Work in Progress

The programmatic protection capabilities are currently in private preview and subject to change.

Next Steps

Configure Guardrails

Detailed Guard configuration options

Use Guardrails

Runtime patterns and best practices

Custom Detectors

Build your own detection methods

Observability

Monitoring and tracing setup