MCP Shark is a Wireshark-like forensic analysis tool for Model Context Protocol (MCP) communications. It captures, inspects, and investigates all HTTP traffic between your IDE and MCP servers.

How does MCP Shark work?

MCP Shark acts as an intermediary gateway between your IDE and MCP servers. It captures all HTTP requests and responses, logs them to SQLite, and provides a real-time web interface for monitoring and analysis.

Which IDEs are supported?

MCP Shark works with any IDE that supports the Model Context Protocol, including Cursor, Windsurf, Claude Code, and any other MCP-compatible development environment. As long as your IDE can connect to MCP servers via HTTP or stdio, MCP Shark can capture and analyze the traffic.

MCP Playground: Safely Testing Tools, Prompts and Resources

What is the MCP Playground?

The MCP Playground is an integrated feature in MCP Shark that provides a safe, isolated environment for testing and exploring MCP servers. Unlike using MCP servers directly in your IDE, the playground lets you:

Test tools without affecting your production workflow
Experiment with prompts and see responses
Explore available resources
Debug server behavior in isolation
Learn how MCP servers work without risk

The playground is bundled with MCP Shark, so you don't need any additional setup or configuration.

Why Use the Playground?

Safety First

Testing MCP servers directly in your IDE can have unintended consequences:

Tools might modify files or configurations
Prompts might trigger expensive API calls
Resources might expose sensitive information
Errors might disrupt your workflow

The playground provides a controlled environment where you can experiment safely.

Learning and Exploration

The playground is perfect for:

Understanding what tools a server provides
Learning how prompts work
Exploring available resources
Testing different parameters and configurations
Documenting server capabilities

Debugging and Troubleshooting

When something goes wrong with an MCP server:

Reproduce issues in the playground
Test different inputs to isolate problems
Compare expected vs. actual behavior
Capture detailed logs and responses

How to Access the Playground

The MCP Playground is accessible directly from MCP Shark's interface:

Start MCP Shark and ensure your MCP servers are configured
Navigate to the "MCP Playground" tab in the interface
Select the MCP server you want to test
Begin exploring tools, prompts, and resources

No additional configuration is needed—the playground uses the same MCP servers configured in MCP Shark.

Testing Tools

Viewing Available Tools

The playground shows you all tools registered by the selected MCP server. For each tool, you can see:

Tool name and description
Required and optional parameters
Parameter types and formats
Expected return values

Calling Tools

To test a tool:

Select the tool you want to test
Fill in the required parameters
Optionally provide optional parameters
Click "Call Tool" to execute
Review the response and any errors

The playground shows you the exact request sent and the complete response received, making it easy to understand tool behavior.

Example: Testing a File Read Tool

Imagine you want to test a file reading tool:

Select the "read_file" tool from the list
Enter a file path as a parameter
Call the tool and see the file contents
Try different file paths to test error handling
Verify the tool only accesses allowed files

This helps you understand the tool's capabilities and limitations before using it in production.

Testing Prompts

MCP servers can provide prompts that help guide AI interactions. In the playground, you can:

View all available prompts from a server
See prompt content and structure
Test how prompts are used in conversations
Understand prompt context and variables

This is especially useful for understanding how MCP servers guide AI behavior and what context they provide.

Exploring Resources

Resources are data sources that MCP servers can provide. In the playground:

Browse available resource URIs
Read resource contents
Understand resource schemas
Test resource access patterns

This helps you understand what data is available and how to access it safely.

Best Practices

1. Test Before Production

Always test new MCP servers or tools in the playground before using them in your IDE. This helps you understand behavior and catch issues early.

2. Document Findings

As you explore servers in the playground, document:

Available tools and their purposes
Parameter requirements and formats
Expected responses and error cases
Any limitations or gotchas

3. Test Edge Cases

Use the playground to test:

Invalid inputs and error handling
Boundary conditions
Missing or optional parameters
Concurrent or rapid requests

Integration with Traffic Capture

One of the powerful features of MCP Shark is that playground activities are also captured in the Traffic Capture view. This means:

All playground tool calls appear in traffic logs
You can review requests and responses in detail
You can export playground sessions for analysis
You can compare playground vs. IDE usage patterns

This creates a complete picture of how MCP servers are being used, both in testing and production.

Use Cases

Server Evaluation

Before adding a new MCP server to your setup, use the playground to evaluate its capabilities, test its tools, and ensure it meets your needs.

Security Auditing

Test tools in the playground to verify they only access expected resources and don't perform unauthorized actions.

Learning and Training

Use the playground to learn how MCP works, understand different server types, and train team members on MCP concepts.

Debugging

When tools fail in your IDE, reproduce the issue in the playground to isolate the problem and test fixes.

Next Steps

Continue exploring MCP capabilities:

How to Capture and Inspect MCP Traffic - Setup guide
Model Context Protocol Deep Dive - Understand MCP fundamentals
How to Use MCP Shark - Complete feature guide