Architecture

The extension is built in Kotlin targeting JVM 21, using the Burp Montoya API. It follows a layered architecture with clear module boundaries.

Layers

┌─────────────────────────────────────────┐
│  1. UI Layer (Swing)                    │
│     MainTab, ChatPanel, SettingsPanel   │
├─────────────────────────────────────────┤
│  2. Context Collection                  │
│     ContextCollector (Burp selections)  │
├─────────────────────────────────────────┤
│  3. Redaction Pipeline                  │
│     Privacy modes, token/host scrubbing │
├─────────────────────────────────────────┤
│  4. Backend Adapters (Pluggable)        │
│     CLI + HTTP backends via registry    │
├─────────────────────────────────────────┤
│  5. Supervisor                          │
│     AgentSupervisor, McpSupervisor      │
├─────────────────────────────────────────┤
│  6. MCP Server                          │
│     Ktor SSE + STDIO, 53+ tools        │
├─────────────────────────────────────────┤
│  7. Scanners                            │
│     Passive AI Scanner, Active Scanner  │
├─────────────────────────────────────────┤
│  8. Audit Logging                       │
│     JSONL + SHA-256 hashing             │
├─────────────────────────────────────────┤
│  9. Alerts                              │
│     Webhook notifications               │
└─────────────────────────────────────────┘

Design Goals

• Modularity: Each layer can be developed, tested, and replaced independently.

• Testability: Redaction is pure (no side effects). Backends are behind interfaces.

• Extensibility: New backends can be added via ServiceLoader without modifying core code. New MCP tools follow a descriptor + handler pattern.

• Determinism: When enabled, context ordering and redaction are stable for reproducible audit trails.

• Privacy-first: Redaction is applied before any data leaves Burp, regardless of the destination.

Key Modules

Package	Purpose
ui/*	Swing UI: MainTab, ChatPanel, SettingsPanel, components (AccordionPanel, ActionCard, ToggleSwitch, PrivacyPill, DependencyBanner).
ui/UiActions	Context menu action definitions and handlers.
ui/UiTheme	Theming and color management.
ui/MarkdownRenderer	Renders AI responses as formatted Markdown in the chat panel.
ui/McpHelpPanel	MCP configuration help and quick-start instructions.
context/*	Context collection from Burp selections (requests, responses, issues).
redact/*	Redaction policies: cookie stripping, token redaction, host anonymization with salt.
backends/*	Backend registry, adapters (Ollama, LM Studio, Gemini, Claude, Codex, OpenCode), diagnostics.
supervisor/*	AgentSupervisor (backend lifecycle, health checks, auto-restart).
mcp/*	KtorMcpServerManager (Ktor/Netty SSE server), McpStdioBridge, McpSupervisor, McpToolCatalog, McpTools, McpToolContext, McpRequestLimiter, McpTls.
scanner/*	PassiveAiScanner, ActiveAiScanner, PayloadGenerator, ResponseAnalyzer, InjectionPointExtractor, AiScanCheck, ActiveScanModels.
audit/*	AuditLogger (JSONL), Hashing (SHA-256).
alerts/*	Webhook alerting for finding notifications.
config/*	AgentSettings (preferences storage, default values).

Entry Point

The extension entry point is BurpAiAgentExtension.initialize(MontoyaApi), which:

1. Initializes the backend registry (built-in + external JARs from ~/.burp-ai-agent/backends/).

2. Creates the audit logger, settings, supervisor, and scanners.

3. Registers the main UI tab and context menu providers.

4. Registers AiScanCheck with Burp Pro's native scanner (with Community Edition fallback).

5. Starts the MCP server if enabled.

Technology Stack

Component	Technology
Language	Kotlin 2.1 (JVM 21)
Burp API	Montoya API 2025.12
HTTP Server	Ktor 3.1.3 (Netty)
Serialization	kotlinx-serialization-json, Jackson
HTTP Client	OkHttp 4.12
MCP SDK	Kotlin SDK 0.5.0
Coroutines	kotlinx-coroutines 1.9.0
Testing	JUnit 5, Mockito-Kotlin
Build	Gradle (Kotlin DSL), Shadow plugin for fat JAR