JSON-RPC Inspector Tool
A free diagnostic tool for testing and debugging JSON-RPC 2.0 endpoints. Make direct RPC calls and see the responses in real time — no setup required.
Free to use · 50 calls/hour as a guest · Sign in for more
Powered by DataGrout · 50 calls/hour as a guest · Create a free account for a higher limit
The fastest way to debug a JSON-RPC endpoint
JSON-RPC 2.0 is a compact remote procedure call protocol that powers everything from AI agent tool calls to blockchain node APIs. Before you wire a JSON-RPC endpoint into a production system, you need to know the method works, the params are accepted, and the response shape matches what you expect.
Connect
Enter any JSON-RPC endpoint URL. Use the Your Servers tab to auto-configure DataGrout-hosted endpoints, or paste any external JSON-RPC address directly.
Inspect
Enter the method name, build your params, and execute a live call. The full response — result or error — renders immediately.
Validate
Confirm methods are reachable, auth is accepted, error codes match the JSON-RPC 2.0 spec, and responses return the shape you expect.
Without an inspector, debugging a JSON-RPC server typically means reading raw HTTP logs, parsing curl output, or writing throwaway test scripts for every method you want to validate. That's friction you don't need — especially when the issue turns out to be a malformed params object or a missing id field.
The JSON-RPC Inspector separates "does my endpoint work?" from "does my application logic work?" Confirm that methods are reachable, auth is accepted, and responses match the spec before your application ever touches the endpoint.
For DataGrout servers, the Your Servers tab auto-configures the endpoint and auth, and an Action dropdown gives you three pre-built options — tools.list, tools.call, and tools.get — plus a Custom method option for any other call. No handshake or protocol lifecycle required.
What the inspector does
Everything you need to validate a JSON-RPC endpoint from first connection to live method execution.
Direct RPC calls in real time
Enter any JSON-RPC 2.0 endpoint URL, select a method, and execute a live call. Responses appear immediately — no setup, no code, no intermediate tooling required.
Authentication support
Supports No Auth, Bearer tokens, and other common auth schemes. Credentials are held in-memory for the current session only and are never stored or logged anywhere.
Action dropdown for DataGrout servers
When using a DataGrout server, an Action dropdown replaces free-form method entry. Choose from tools.list, tools.call, tools.get, or Custom method — the endpoint and auth are pre-configured automatically.
Inline method and parameter editor
Enter the method name and construct your params object directly in the editor. The tool validates your JSON before execution so you catch malformed payloads before they reach the server.
Real-time response display
Responses render immediately after execution. Review the full JSON-RPC result or error object — including error code, message, and data fields — inline without switching contexts.
Error code visibility
JSON-RPC error responses surface the code, message, and optional data fields clearly, making it easy to distinguish application errors from protocol-level violations.
50 calls per hour, free
Free users get 50 calls per hour — enough for active diagnostic work. Once you reach the limit, you'll be prompted to create a free DataGrout account to continue.
No credentials stored
Auth tokens and API keys are used only for the duration of your session. Nothing is persisted server-side. Only anonymized usage statistics are tracked to improve the tool.
How to use the JSON-RPC Inspector
Four steps from a blank form to a validated JSON-RPC endpoint.
Enter your JSON-RPC endpoint URL
Paste the full URL of your JSON-RPC server (e.g. https://api.example.com/jsonrpc). Works with any JSON-RPC 2.0 endpoint — blockchain nodes, microservices, DataGrout servers, or local dev instances.
Select an authentication method (if required)
Choose from No Authentication, Bearer Token, Basic Auth, or OAuth 2.0. Credentials are held in-memory for your session only and are never stored or logged.
Select an action or enter a custom method
For DataGrout servers, choose an action from the dropdown: tools.list (list available tools), tools.call (call a tool), tools.get (get tool details), or Custom method for any other JSON-RPC call. For external servers, enter the method name directly (e.g. eth_blockNumber, getInfo) and provide a JSON params object.
Click "Execute Request" to see the response
The full JSON-RPC response — result or error — appears in the Response Log in real time. Review the output, check error codes, and iterate without leaving the tool.
Your endpoint passes inspection. Now make it agent-accessible.
The JSON-RPC Inspector confirms your endpoint works. DataGrout Hub is the next step — it wraps your JSON-RPC service as a governed MCP server, making it discoverable by AI agents alongside 1,000+ other enterprise tools, with mTLS identity, semantic tool discovery, policy enforcement, and tamper-evident audit trails built in.
- Expose JSON-RPC methods as named, schema-aware MCP tools
- Agents discover methods by goal — not by knowing method names in advance
- Credential vaulting, PII redaction, and human approval built in
- Private Connectors for internal JSON-RPC services (no firewall changes)
JSON-RPC Inspector → DataGrout Hub
Frequently asked questions
What is the JSON-RPC Inspector?
The JSON-RPC Inspector is a free diagnostic tool for testing and debugging JSON-RPC 2.0 endpoints. It lets you make direct RPC calls and see the responses in real time — no code, no configuration, no account required to get started.
What is JSON-RPC 2.0?
JSON-RPC 2.0 is a lightweight remote procedure call protocol that uses JSON for encoding. A client sends a request object with a method name, optional params, and an id. The server returns a result or error. Because it's transport-agnostic, it's commonly used over HTTP, WebSockets, and stdio — and it's the underlying wire protocol for MCP (Model Context Protocol).
How is JSON-RPC different from REST?
REST maps operations to HTTP verbs and URL paths. JSON-RPC uses a single endpoint and encodes the operation name in the request body. This makes JSON-RPC simpler for tightly-defined RPC-style interfaces. Many AI agent frameworks — including MCP — use JSON-RPC as their underlying wire protocol.
What DataGrout server actions are available?
DataGrout servers expose their tools via JSON-RPC without requiring the full MCP protocol lifecycle. The Action dropdown offers three pre-built options: tools.list (list available tools), tools.call (call a specific tool), and tools.get (get tool details). A fourth option — Custom method — lets you enter any arbitrary JSON-RPC method name. The Your Servers tab auto-configures the endpoint URL and authentication for any DataGrout-hosted server.
Can I test a local JSON-RPC server?
Yes. If your local server is reachable via a URL — including localhost with a tunnel like ngrok or Cloudflare Tunnel — paste it directly into the endpoint field and send requests immediately.
What are the rate limits?
Free users get 50 calls per hour. This is generous for diagnostic testing and helps prevent abuse. Once you reach the limit, you'll be prompted to create a free DataGrout account for continued access. Need more? The full DataGrout Playground supports intelligent workflows without per-call rate limits.
Are my credentials and tokens stored?
No. Your credentials and tokens are never stored. They are only used for the current session and are not logged or saved anywhere. Only anonymized usage statistics are tracked to improve the tool.
How does the JSON-RPC Inspector relate to DataGrout?
DataGrout built this tool for developers working with JSON-RPC based services. The Model Context Protocol (MCP) — which DataGrout Hub is built on — uses JSON-RPC as its wire format. Once your endpoint is tested and validated here, DataGrout Hub can connect it as a governed MCP server alongside 1,000+ other enterprise tools under a single managed endpoint.
Ready to make your JSON-RPC endpoint agent-accessible?
DataGrout Hub wraps your JSON-RPC service as a governed MCP server — discoverable, auditable, and enterprise-ready.