JSON Contracts
JSON contract registry and validator for structured LLM and agent outputs.
MCP server · by json-contracts
About
JSON Contracts is an MCP server published by json-contracts. Marketplaces we read that list it: 1 (Official MCP Registry). We first saw it on 2026-10-11 and have recorded no change since. As of our marketplace pass on 2026-10-12.
What it asks for
- Runs on your machine
- Settings: 1
What it declares, asks for and runs, in full
Only install plugins from developers you trust. We list what marketplaces publish and do not test plugins.
Works with
- Claude Code
- Codex
- Cursor
- VS Code
- Copilot CLI
A one-click link opens the client, which asks you to confirm before it adds the server.
From the marketplaces that list it and the MCP transport it declares, as each client documents them. We do not test plugins.
Connect
Commands and configs built only from what its marketplaces declare. We do not run them for you and do not test plugins.
As a local MCP server: npm package
Built from what Official MCP Registry declares.
claude mcp add --transport stdio json-contracts -- npx -y json-contracts[mcp_servers.json-contracts]
command = "npx"
args = ["-y", "json-contracts"]{
"mcpServers": {
"json-contracts": {
"command": "npx",
"args": [
"-y",
"json-contracts"
]
}
}
}Optional settings it also lists: JSON_CONTRACTS_DIR.
We do not store launch arguments. If the server needs any, its own documentation names them.
Where it is published
| Marketplace | Status | Version | Figures | Verified | First seen |
|---|---|---|---|---|---|
| Official MCP Registry (Open the registry record) | Listed | 0.1.2 | Forks (GitHub): 0 Stars (GitHub): 1 |
Not marked |
Each figure is the marketplace's own and is never added up across marketplaces. A marketplace that publishes no figure shows none: no number is not zero.
What changed
Nothing has moved on this plugin since we started watching it.
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