Use JSON Schema Validator with your AI.
Connect your account once and let the AI you already use work with it, without building another integration. Validates raw LLM text outputs against JSON Schemas to detect missing parameters, type mismismatches, and hallucinations.
Developed, maintained, and hosted by Vinkius.
MCP VERIFIED · PRODUCTION READY · VINKIUS GUARANTEED
Waiting for input…
Works with modern AI clients that support MCP, including ChatGPT, Claude, Cursor, and more.
Complete set · 3 capabilities
The complete JSON Schema Validator capability set.
These are the exact actions your AI can choose when you ask it to work with JSON Schema Validator.
01-03
3 capabilities in this set.
Part of 3 available through JSON Schema Validator.
- 01
Extract JSON from text
A utility to isolate the JSON component from a messy LLM text string
- 02
Get validation summary
Provides a high-level overview of multiple validation attempts to track model reliability over time
- 03
Validate function call
Validates a raw LLM text string against a specific JSON Schema to identify structural and logical errors
Observed, not estimated
807ms average. Fast in production.
JSON Schema Validator is checked daily against the live service.
- Fastest day
- 623ms
- Slowest day
- 985ms
- 14-day trend
- Slowing+43%
Connect your client
One URL. Every client.
Activate the Connector, copy your link, and paste it into the client you already use. 3 capabilities arrive ready to run.
Preview access · not provider authentication
The vk_preview_* token belongs to Vinkius preview infrastructure. It lets Claude discover and display the capabilities of JSON Schema Validator, so you can see the experience inside your AI.
It does not authenticate your account with JSON Schema Validator. Actions requiring credentials or live account data may not run until you activate the Connector and authorize the service.
JSON Schema Validator Connector
You're all set. Choose your MCP client and follow the setup instructions.
https://edge.vinkius.com/vk_preview_21yoFjCa6YURZm8sCCyeJadvPgEYlKfXVV7HUnII/mcpClaude Desktop
Follow the steps below to connect in seconds.
- 1In Claude Desktop, open Settings → Connectors.
- 2Click “Add custom connector” and paste the connector link above as the remote MCP server URL.
- 3Click Add and start a new chat — JSON Schema Validator capabilities are ready to use.
{
"mcpServers": {
"json-schema-function-call-validator-mcp": {
"url": "https://edge.vinkius.com/vk_preview_21yoFjCa6YURZm8sCCyeJadvPgEYlKfXVV7HUnII/mcp"
}
}
}- Claude
- ChatGPT
- Cursor
- VS Code
- Windsurf
- Claude Code
- JetBrains
- Cline
Step-by-step instructions for each client are in the guide. How to connect
FAQ
Questions JSON Schema Validator owners ask.
- 01
How does the validator handle conversational text around the JSON?
The extract_json_from_text capability specifically isolates the JSON block by finding the first and last curly braces, allowing the validator to ignore surrounding markdown or conversational filler.
- 02
What kind of errors does validate_function_call detect?
It detects three main error types: missing required parameters, type mismatches (e.g., a string where an integer is expected), and hallucinations (parameters present in the output but not in the schema).
- 03
Can I track the reliability of my LLM over time?
Yes, you can use get_validation_summary by providing a history of previous validation results to calculate average validity and a qualitative reliability rating.
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