Chronos — Time-Travel Debugging MCP Server

Chronos is an MCP (Model Context Protocol) server that enables AI agents to perform time-travel debugging on any language runtime.

Features

• Multi-language support: Native (C/C++/Rust via ptrace), Python (sys.settrace), Java (JDWP), Go (Delve)
• eBPF tracing: Low-overhead kernel-level tracing via aya
• Time-travel queries: Reconstruct call stacks, detect races, trace variable origins
• Persistent sessions: BLAKE3 content-addressable storage with LZ4 compression
• Golden trace comparison: Detect regressions by diffing execution traces
• 32+ MCP tools: Full debugging API for AI agents

Quick Start

Prerequisites

• Rust 1.77+
• For Python: python3 in PATH
• For Java: java + javac in PATH
• For Go: dlv (Delve) in PATH

Build

cargo build -p chronos-mcp --release

Run as MCP server (stdio mode)

./target/release/chronos-mcp --stdio

Configure with Claude Desktop / OpenCode

Add to your MCP config:

{
  "mcpServers": {
    "chronos": {
      "command": "/path/to/chronos-mcp",
      "args": ["--stdio"]
    }
  }
}

MCP Tools

Capture

Tool	Description
debug_run	Run a program under time-travel capture
debug_attach	Attach to a running process

Query

Tool	Description
query_events	Filter and paginate trace events
get_event	Get a single event by ID
reconstruct_call_stack	Rebuild call stack at any point
detect_races	Find data races in the trace
query_causality	Trace memory access causality
find_variable_origin	Track where a variable was set
get_execution_summary	Overview of the execution
expand_hotspot	Top N hot functions
get_saliency_scores	CPU saliency per function

Persistence

Tool	Description
save_session	Persist current session to disk
load_session	Restore a saved session
list_sessions	List all saved sessions
delete_session	Remove a session
compare_sessions	Diff two sessions for regressions

Architecture

chronos-mcp          ← MCP server (32+ tools)
├── chronos-native   ← ptrace adapter (C/C++/Rust)
├── chronos-ebpf     ← eBPF uprobes via aya
├── chronos-python   ← sys.settrace adapter
├── chronos-java     ← JDWP client adapter
├── chronos-go       ← Delve DAP adapter
├── chronos-capture  ← AdapterRegistry, CaptureSession
├── chronos-query    ← QueryEngine (time-travel queries)
├── chronos-store    ← redb + BLAKE3 CAS + TraceDiff
└── chronos-domain   ← Shared types (TraceEvent, EventData)

Docker

docker build -t chronos-mcp .
docker run -v chronos-data:/data/chronos chronos-mcp

Development

cargo test --workspace --lib -- --test-threads=1
cargo bench -p chronos-query
cargo bench -p chronos-store

License

MIT