Soma MCP Server
Give your AI agent the one thing it can't do for itself: actually run code against tests and prove it passed.
Soma is an execution-verified code service. This MCP server exposes two tools:
soma_verify_code— run candidate code against tests inside an isolated sandbox; get a PASS/FAIL verdict plus a signed, offline-checkable certificate (Ed25519). Use it to independently confirm code works before trusting it.soma_generate_verified_code— ask Soma to write code for a task; when the task is verifiable, the returned code has already been executed against derived tests, with a certificate attached.
15+ languages are supported for verification (Python, JavaScript/TypeScript, Go, C/C++, Java, Rust, Ruby, PHP, Bash, and more).
Install
Requires Node.js 18+. Runs over stdio.
Add to your MCP client config (Claude Desktop, Cursor, etc.):
{
"mcpServers": {
"soma": {
"command": "npx",
"args": ["-y", "soma-verify-mcp"],
"env": {
"SOMA_API_KEY": "YOUR_SOMA_KEY"
}
}
}
}
- Claude Desktop:
Settings → Developer → Edit Config, add the block above, restart. - Cursor:
Settings → MCP → Add, or drop the same block in~/.cursor/mcp.json.
Configuration
| Env var | Required | Default | Purpose |
|---|---|---|---|
SOMA_API_KEY | yes | — | Your Soma API key. |
SOMA_BASE_URL | no | https://170-9-236-56.sslip.io | Soma API base URL. |
SOMA_TIMEOUT_MS | no | 300000 | Per-request timeout. |
Get a free preview key: contact centrum.arvind@gmail.com (free tier during the preview).
Tools
soma_verify_code
Run code against tests and return a signed verdict.
language(string) — e.g.python,javascript,go,rust.code(string) — the complete source to verify.tests(array) — one of:- function mode (default):
[{ "input": [arg1, arg2], "expected": value }]plusentrypoint(the function name). - stdio mode: set
mode: "stdio"and[{ "stdin": "...", "expected_stdout": "..." }]; no entrypoint.
- function mode (default):
entrypoint(string, optional) — function name for function mode.mode("function"|"stdio", optional).
Returns: verdict, tests_passed, tests_total, and a signature / public_key / sig_alg you can check offline.
soma_generate_verified_code
Get code for a task, executed against derived tests before it's returned.
prompt(string) — the coding task. Include concrete input/output examples (e.g.>>> f(2) == 4) so the result is verifiable rather than best-effort.max_tokens(int, optional, default 1500).
Returns: the code, certified (bool), and a certificate (verdict, tests_passed, tests_total) when verification passed. If a task isn't verifiable, output is returned uncertified and clearly labeled — never a false "verified".
What the certificate means
A certificate attests that the listed tests passed inside an isolated sandbox at generation time. It is signed (Ed25519) and checkable offline against the returned public key. It is not a warranty of fitness for any purpose — review output before production use.
Privacy
No training on your prompts. See the Soma Privacy & Data Policy at ${SOMA_BASE_URL}/privacy.
License
MIT.