JSON Contracts vs Contracts Wizard
A side-by-side look at the JSON Contracts and Contracts Wizard MCP servers: transport, auth, tools, quality signals, and the config to install either one in Claude, Cursor, Windsurf or VS Code.
Verdict: choose JSON Contracts for legal work as a local process; choose Contracts Wizard for legal over a hosted endpoint. You can also run both side by side in one mcpServers block.
Which MCP server should you choose?
Choose JSON Contracts when
- You need dedicated capabilities in the Legal domain.
- You prefer a local stdio subprocess transport.
- You have the keys it needs:
JSON_CONTRACTS_DIR.
Choose Contracts Wizard when
- You need dedicated capabilities in the Legal domain.
- You prefer a remote HTTP/SSE transport.
- Its auth model fits you: No auth required.
Feature & specification comparison
Rows where the two servers differ are marked.
| Spec | ||
|---|---|---|
| Category | Legal | Legal |
| Quality signal | 35/100 · Fair | 56/100 · Good |
| Install command | Confirmed | Confirmed |
| Transport | Local subprocess (stdio) | Remote HTTP/SSE |
| Auth | Not declared | No auth required |
| Pricing | Not declared | Free |
| Required env vars | JSON_CONTRACTS_DIR |
Tools & capabilities
JSON Contracts tools
No tool names declared yet. Check the project README from the listing page.
Contracts Wizard tools
No tool names declared yet. Check the project README from the listing page.
Ready-to-paste client configs
Paste either block (or both) into your client config, e.g. claude_desktop_config.json or ~/.cursor/mcp.json. We only show a config when the install command is confirmed.
JSON Contracts
{
"mcpServers": {
"json-contracts": {
"command": "npx",
"args": [
"-y",
"json-contracts@latest"
],
"env": {
"JSON_CONTRACTS_DIR": "YOUR_JSON_CONTRACTS_DIR_HERE"
}
}
}
}
Contracts Wizard
{
"mcpServers": {
"openzeppelin-contracts-wizard": {
"url": "https://mcp.openzeppelin.com"
}
}
}
Frequently asked questions
JSON Contracts is categorized under Legal and uses a local stdio subprocess. Contracts Wizard belongs to Legal and uses a remote HTTP/SSE transport. Pick JSON Contracts for legal work and Contracts Wizard for legal.
Copy the mcpServers block from the config section on this page into your client's config (for example claude_desktop_config.json or ~/.cursor/mcp.json), then fully restart the client.
JSON Contracts has no declared pricing — check the project's own site. Contracts Wizard is listed as free. Auth: no auth required. If a server needs environment variables such as API keys, define them under the env key in your client's MCP config.
Yes. MCP clients support multiple servers: add json-contracts and openzeppelin-contracts-wizard as separate keys in the same mcpServers object, and your assistant will call tools from either one.
On AllMCPs, JSON Contracts has a quality signal of 35/100 (Fair) with 1 views, 0 installs and 1 GitHub stars. Contracts Wizard has 56/100 (Good) with 1 views, 0 installs and 295 GitHub stars.