Ouroboros MCP Server

by q00 Your server? Claim it

local only

Ouroboros runs on your own machine — the client starts it, so there is no endpoint to ping. 29 070 installs a week from pypi. Last commit 9 Sep 2026.

Pins an acceptance spec; the verify command and expected output never enter the success contract.

Installs per day peak 11 081 · avg 4 760 · +11% w/w

a month agotoday

29 070

Installs / week

pypi · ouroboros-ai

5803

Stars

60 open issues

9 Sep 2026

Last commit

0 releases in 90 days

MIT

License

Python

What the code does

We read the source, 12 h ago · rules 3dff92dd89df

Capabilities

What this server is able to do. For an MCP server this is often the job itself — a terminal server runs commands because that is what it is for. Listed so you know what you are plugging in, not as an accusation.

Runs a command on install [пакет] package.json:1

setup.py: выполняет код при установке пакета

File ships in the package but is absent from the source [пакет] src/ouroboros/_version.py:1

этот файл ставится пользователю, но в репозитории его нет

Runs an external command src/ouroboros/auto/checkpoint_commits.py:154, src/ouroboros/bigbang/brownfield.py:101, src/ouroboros/cli/commands/mcp_doctor.py:407 и ещё 51

    result = subprocess.run(

Unsafe deserialization src/ouroboros/cli/runtime_activation.py:343, [пакет] src/ouroboros/cli/runtime_activation.py:343

        loaded = yaml.load(snapshot.contents.decode("utf-8"), Loader=_UniqueKeyLoader)

Known vulnerability in the package ouroboros-ai · GHSA-c4m7-2gwp-vw76

Known vulnerability in the package ouroboros-ai · GHSA-jv2h-4p9v-wf5w

Known vulnerability in the package ouroboros-ai · PYSEC-2026-2857

Dumps the whole environment src/ouroboros/plugin/firewall.py:638, src/ouroboros/providers/goose_cli_adapter.py:311, src/ouroboros/runtime/child_env.py:67 и ещё 6

    env = dict(os.environ)

Is this your server and something here is wrong? Tell us — corrections are free and do not require a plan.

This code can reach further than it looks

We found places where it runs commands, builds paths or queries from values it is given. None of that is a flaw by itself — it becomes one when the code changes, and code changes quietly between releases. We re-read it on every one.

Connect this server

This server runs on your own machine — install it with the package manager and the client starts it for you. Package name taken from the official registry entry.

Claude Code Claude Desktop Codex Cursor VS Code

run in your terminal

claude mcp add ouroboros -- uvx ouroboros-ai

~/Library/Application Support/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "ouroboros": {
      "args": [
        "ouroboros-ai"
      ],
      "command": "uvx"
    }
  }
}

~/.codex/config.toml

[mcp_servers.ouroboros]
command = "uvx"
args = ["ouroboros-ai"]

.cursor/mcp.json

{
  "mcpServers": {
    "ouroboros": {
      "args": [
        "ouroboros-ai"
      ],
      "command": "uvx"
    }
  }
}

.vscode/mcp.json

{
  "mcpServers": {
    "ouroboros": {
      "args": [
        "ouroboros-ai"
      ],
      "command": "uvx"
    }
  }
}

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Ouroboros — questions

Answers built from our own checks of this server.

Why is there no uptime for Ouroboros?

Ouroboros runs on your own machine over stdio — there is no network address to reach, so uptime cannot be measured for it by anyone. What can be measured is adoption: the pypi package ouroboros-ai was installed 29 070 times last week.

How do I connect Ouroboros?

Copy the ready config from this page — we generate it for Claude Code, Claude Desktop, Codex, Cursor and VS Code, each with the file path that client actually reads. It runs locally, so the command pulls ouroboros-ai straight from pypi; nothing to host, nothing to sign up for.

How many people use Ouroboros?

The pypi package ouroboros-ai was installed 29 070 times in the last week. Week over week that is +11%. We show installs rather than GitHub stars on purpose: a star is a bookmark, an install is someone actually running it.

Is Ouroboros open source?

Yes — it is published under the MIT licence, written in Python, 5 803 stars on GitHub and 60 open issues. The source link is on this page, so you can read exactly what it does with your data before you connect it.