tda MCP — Use Cases, Install & Live Demo

Why use it

Key features

Runs from a single JAR, fully offline
Parses multi-dump log files and summarizes across dumps
Deadlock detection + long-running thread tracking
Virtual-thread (Project Loom) pinning analysis

Live Demo

What it looks like in practice

tda.replay ▶ ready

0/0

Install

Pick your client

~/Library/Application Support/Claude/claude_desktop_config.json · Windows: %APPDATA%\Claude\claude_desktop_config.json

{
  "mcpServers": {
    "tda": {
      "command": "TODO",
      "args": [
        "See README: https://github.com/irockel/tda"
      ],
      "_inferred": true
    }
  }
}

Open Claude Desktop → Settings → Developer → Edit Config. Restart after saving.

~/.cursor/mcp.json · .cursor/mcp.json

{
  "mcpServers": {
    "tda": {
      "command": "TODO",
      "args": [
        "See README: https://github.com/irockel/tda"
      ],
      "_inferred": true
    }
  }
}

Cursor uses the same mcpServers schema as Claude Desktop. Project config wins over global.

VS Code → Cline → MCP Servers → Edit

{
  "mcpServers": {
    "tda": {
      "command": "TODO",
      "args": [
        "See README: https://github.com/irockel/tda"
      ],
      "_inferred": true
    }
  }
}

Click the MCP Servers icon in the Cline sidebar, then "Edit Configuration".

~/.codeium/windsurf/mcp_config.json

{
  "mcpServers": {
    "tda": {
      "command": "TODO",
      "args": [
        "See README: https://github.com/irockel/tda"
      ],
      "_inferred": true
    }
  }
}

Same shape as Claude Desktop. Restart Windsurf to pick up changes.

~/.continue/config.json

{
  "mcpServers": [
    {
      "name": "tda",
      "command": "TODO",
      "args": [
        "See README: https://github.com/irockel/tda"
      ]
    }
  ]
}

Continue uses an array of server objects rather than a map.

~/.config/zed/settings.json

{
  "context_servers": {
    "tda": {
      "command": {
        "path": "TODO",
        "args": [
          "See README: https://github.com/irockel/tda"
        ]
      }
    }
  }
}

Add to context_servers. Zed hot-reloads on save.

claude mcp add tda -- TODO 'See README: https://github.com/irockel/tda'

One-liner. Verify with claude mcp list. Remove with claude mcp remove.

Use Cases

Real-world ways to use tda

Diagnose a JVM hang from thread dumps with TDA

👤 Java backend engineers ⏱ ~20 min advanced

When to use: Production JVM went unresponsive; you have a series of kill -3 dumps.

Prerequisites

tda.jar downloaded — github.com/irockel/tda releases
Java 21+ installed — For Project Loom analysis features

Flow

Parse the log

parse_log on /tmp/threaddumps.log. Summarize: how many dumps, threads per dump.✓ Copied

→ Dump overview
Check for deadlocks

check_deadlocks across all dumps. Which threads, which locks?✓ Copied

→ Deadlock cycles if any
Find long-running threads

find_long_running threads persisting across all dumps. What are they doing?✓ Copied

→ List with stack heads

Outcome: A specific thread + lock + code path responsible for the hang.

Pitfalls

Scripts printing to stdout corrupt the JSON-RPC stream — Use java -Djava.awt.headless=true -jar tda.jar --mcp without wrapping in any script that also prints

Hunt virtual-thread carrier pinning in a Loom app

👤 Teams adopting Project Loom ⏱ ~30 min advanced

When to use: Virtual threads aren't giving the concurrency you expected — suspect pinning.

Flow

Capture dumps during load

Collect thread dumps at peak load; parse_log them in TDA.✓ Copied

→ Dumps loaded
Analyze

analyze_virtual_threads. Show carrier pinning hotspots and the Java code pinning them (typically synchronized blocks or native methods).✓ Copied

→ Pinning list with source hints

Outcome: Targeted fixes (ReentrantLock instead of synchronized, etc.) backed by evidence.

Identify threads stuck in native methods

👤 Performance engineers on JNI-heavy apps ⏱ ~15 min advanced

When to use: Your app integrates with native libs and you suspect blocking native calls.

Flow

List native-blocked threads

get_native_threads for dump #3. Which native methods are they stuck in?✓ Copied

→ Thread + native frame list

Outcome: Targeted review of specific JNI call sites.

Combinations

Pair with other MCPs for X10 leverage

tda + prometheus

Correlate thread-level findings with JVM metrics

TDA says lock X is contended — show JVM thread_blocked_seconds for the same window from Prometheus.✓ Copied

tda + github

Turn findings into issues with code pointers

For the top 3 TDA findings, open a GitHub issue linking the suspect Java source lines.✓ Copied

Tools

What this MCP exposes

Tool	Inputs	When to call	Cost
parse_log	path: str	First step, always	local CPU
get_summary		Overview before digging	0
check_deadlocks		Hang diagnosis	0
find_long_running	min_dumps?: int	Persistent threads	0
analyze_virtual_threads		Loom diagnostics	0
get_native_threads	dump_index?: int	JNI suspicion	0
get_zombie_threads		Unresolved memory relocations	0
clear		Reset before parsing a new log	0

Cost & Limits

What this costs to run

API quota: None
Tokens per call: Thread dumps are huge — 20k+ tokens per full dump. Summarize before dumping to chat
Monetary: Free
Tip: Use get_summary/find_long_running narrowing before asking for full stacks

Security

Permissions, secrets, blast radius

Credential storage: None

Data egress: None — entirely local file parsing

Troubleshooting

Common errors and fixes

MCP handshake corrupts

Run JAR exactly per README (headless + --mcp, no wrapper scripts printing to stdout)

parse_log fails on custom dump formats

Ensure dumps are standard HotSpot format; some APMs add prefixes TDA can't parse

Memory blows up on huge logs

Increase JVM heap for tda.jar: -Xmx4g or split the log into chunks

Alternatives

tda vs others

Alternative	When to use it instead	Tradeoff
FastThread / other online analyzers	You're okay uploading dumps to a third party	Data leaves your network
async-profiler + flame graphs	You have live control and want sampling profiler not dumps	Different artifact; needs agent attach

More

Resources

📖 Read the official README on GitHub

🐙 Browse open issues

🔍 Browse all 400+ MCP servers and Skills