Velaris MCP Server

An AI wrote you a script. Run it anyway. A language where a function's signature declares what it may touch - and the runtime refuses anything you did not allow, whatever the code says about itself. It runs locally over stdio via the published package.

People who work with compiler, effect system and formal verification and want it reachable from Claude, Cursor, VS Code, or another MCP client. The project is written in Python.

VERIFIED ACTIVE

LAST COMMIT 2026-09-15 · ★ 3 · #26 OF 168 MAINTAINED DEVELOPER TOOLS · VERIFIED 2026-09-18

MIT · Python servers · how we verify → /methodology

01 · Install Velaris

Claude Code

claude mcp add gowrishankar-infra-velaris-lang -- npx -y velaris-lang

Claude Desktop / Cursor / VS Code - add to config

{
  "mcpServers": {
    "gowrishankar-infra-velaris-lang": {
      "command": "npx",
      "args": [
        "-y",
        "velaris-lang"
      ]
    }
  }
}

Same JSON for Cursor. For VS Code, rename the top-level key from `mcpServers` to `servers`.

Using another client? Same JSON, different key

Claude Desktop · mcpServers

Cursor · mcpServers

VS Code · servers

Windsurf · mcpServers

Zed · context_servers

Cline · mcpServers

Roo Code · mcpServers

Continue · mcpServers

LibreChat · mcpServers

Gemini CLI · mcpServers

Codex CLI · mcp_servers

Full setup guides: every client.

02 · Evidence

Security posture

What to check before giving this server access to your agent - from the registry, GitHub, and our own probes. We don't score safety; we show what's verifiable.

runs as local process (stdio) - runs on your machine with your user's permissions

repo age created 2026-08-16 - young repo, little track record yet

license MIT - declared in the repository

npm package velaris-lang - unscoped; check the name against the project README before installing

registry namespace io.github.gowrishankar-infra is GitHub-verified and matches the repo owner

03 · What Velaris can do

Prose above is summarized from the project's README and registry record - no invented capabilities.

Latest releases

v8.2.1 · 2026-09-15

A patch release with no features. Under 8.2.0, printing one kind of · counterexample ended in a Python traceback instead of its error, and the · release workflow's Marketplace job ended green having published nothing.…

v8.2.0 · 2026-09-15

A minor version with no language features. It is about what holds Velaris · to what it says: tests, gates, and the work of keeping them running. Along · the way the new suites found holes, and they are fixed here…

v8.1.1 · 2026-09-14

A patch release with one fix. Compatibility: a patch under STABILITY.md · rule 1, because it refuses no program that legitimately worked. A false · promise that a planted cache entry let through now fails - before the…

04 · Who maintains Velaris

Velaris is maintained by gowrishankar-infra. It's the only MCP server we track from this author; the repo dates to Aug 2026.

05 · Facts

repository: github.com/gowrishankar-infra/velaris-lang
website: https://gowrishankar-infra.github.io/velaris-lang/
category: developer tools - ranked #26 of 168 actively-maintained developer tools servers as of 2026-09-18.
release cadence: 10+ releases in the last 90 days (latest 2026-09-15)
registry: io.github.gowrishankar-infra/velaris (active, first published 2026-09-12 · 9 versions)
packages: pypi:velaris-lang · npm:velaris-lang

06 · Velaris FAQ

What is Velaris?

Is Velaris still maintained?

Yes - as of 2026-09-18, its last commit was 2026-09-15 and it shipped 10+ releases in the last 90 days. We re-verify nightly.

How do I install Velaris?

Run `npx -y velaris-lang`. You can also paste the ready-made client config above.

Does Velaris run locally?

Yes - it's a stdio server: it runs on your machine (via npx) with your user's permissions. Your data stays local unless the server itself calls external APIs.

07 · Alternatives to Velaris

Alternatives to Velaris

Maintained developer tools servers if Velaris isn't the fit.

Pairs well with

Servers that cover what Velaris doesn't - only shown when the pairing reason fits the companion.

More developer tools MCP servers · Grid Proof · Markupr Plus · Batch Review · Grok MCP · Proof Flow

More Python MCP servers · Link · Ipybox · Chart Library - Market-state research · Greptimedb MCP Server · Ihalent · see all