
Connect JSON Schema Function Call Validator to your AI
Set it up once and it works in ChatGPT, Claude, Cursor, and any other client you love. It all runs safely in the background, so you can relax and focus on what really matters. Stop your agents from sending broken function calls.
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.
Your AI does the work. We keep it safe and sound.
No other AI tool gives you this. Your workflow runs in the client you already love, your account stays protected, and you decide what the agent can and cannot do. It is the whole reason to make the switch.
Each Connector lives inside our infrastructure, the same place where your workflow runs. The three things below are already part of it, working quietly in the background so you never have to think about them. Nothing to add, nothing to set up, nothing to worry about.

Each Connector runs inside its own sealed environment.
Each Connector runs inside its own sealed V8 runtime — no access to your files, your system, or other servers. A Connector never sees past its own request.
One switch stops every agent. Instantly.
One action deactivates every Connector, revokes every token, and ends every session at once. AI Governance keeps the record.
Spending limits that pause instead of surprise.
Every user keeps their own connections and credentials, isolated from everyone else. Anything that would cross your spending limit is held for your approval, not billed.
Three controls, built into the layer your AI connects through.
Curated set · 3 capabilities
We ship only the actions that matter.
01-03
3 capabilities in this set.
Part of 3 available through JSON Schema Validator.
- 01
Extract JSON from text
This capability pulls a clean JSON object out of a messy string of text. It's perfect for when your agent wraps its data in conversational filler.
- 02
Get validation summary
This capability provides a high-level overview of multiple validation attempts. Use it to monitor how your model's reliability changes over time.
- 03
Validate function call
This capability checks a raw text string against a specific JSON Schema. It flags missing parameters, type mismatches, and hallucinated keys.
Real work
What teams actually run
API Orchestration
Your agent extracts a JSON payload from a chat response to trigger a specific capability or API call.
Data Integrity Checks
You validate that an agent's generated data matches a strict schema before saving it to a database.
Model Benchmarking
You use validation summaries to see if a new prompt or model version improves function calling accuracy.
Error Handling
Your agent detects a missing parameter and uses that info to retry the request correctly.
One connector, every AI
JSON Schema Validator works with the most popular AI clients.
These are the most popular clients, each with a step-by-step guide: one link, set up once, with governance and visibility built in. And because everything runs on the MCP standard, the same connection also works in any other compatible client — nothing to rebuild.
Claude
ChatGPT
Gemini
Perplexity
Grok
Microsoft Copilot
Cursor
VS Code
Windsurf
JetBrains
Cline
LangChain
Vercel AI SDK
Lovable
Z.ai
Raycast
Qwen Code
Kimi Code
Le ChatBuilding your own app? The connector is yours to use.
You don't need a client to put JSON Schema Validator to work: the same hosted connection plugs into your own applications and agent code, with the same governance on every request. Build with it, chat with it — one connection for both.
Observed, not estimated
884ms average. Fast in production.
JSON Schema Validator is checked daily against the live service.
- Fastest day
- 709ms
- Slowest day
- 1049ms
- 14-day trend
- Improving-23%
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
Guided setup for Claude? Set up JSON Schema Validator in Claude and other AIs
Who it's for
Built for the work JSON Schema Validator owners hand off.
This is for developers building production-grade agentic workflows that require strict data structures.
- 01
AI Engineer
Building agents that must call specific APIs without syntax errors.
- 02
LLM Developer
Testing model reliability and prompt effectiveness through validation metrics.
- 03
Backend Developer
Ensuring incoming AI data matches the database or API requirements.
FAQ
Questions JSON Schema Validator owners ask.
- 01
How does this MCP handle messy text?
It uses the extraction capability to find and isolate the JSON block within a larger string of conversational text.
- 02
Can I use this with any AI client?
Yes, it works with any MCP-compatible client like Claude, Cursor, or Windsurf.
- 03
What kind of errors does it catch?
It catches missing required parameters, type mismatches, and hallucinated keys that aren't in your schema.
- 04
How do I track model performance?
You can use the validation summary capability to get high-level metrics on multiple validation attempts.
- 05
Do I need to host this myself?
No, Vinkius hosts and manages the MCP for you.
- 06
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.
- 07
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).
- 08
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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Connect JSON Schema Validator to Claude, Cursor, ChatGPT & more
