topos

<p align="center">
  <picture>
    <source media="(prefers-color-scheme: dark)" srcset="https://raw.githubusercontent.com/Krv-Labs/topos/main/docs/source/_static/topos-logo-dark.svg">
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    <img src="https://raw.githubusercontent.com/Krv-Labs/topos/main/docs/source/_static/topos-logo.svg" alt="Topos" width="400">
  </picture>
</p>

<h3 align="center">the agent harness for structural code quality</h3>

<p align="center">
 Topos measures complexity, coupling, risky data flows, and agent cognitive load, then gives your agent a concrete target&mdash;from SLOP to PLATINUM.
</p>

<p align="center">
  <a href="#what-topos-checks"><img src="https://raw.githubusercontent.com/Krv-Labs/topos/main/docs/source/_static/topos-lattice-badge.svg" alt="Topos self-evaluation: SIMPLE, COMPOSABLE, SECURE, NAVIGABLE results for the core crates"></a>
  <a href="https://github.com/mcp/Krv-Labs/topos"><img src="https://img.shields.io/badge/VS_Code-Install_MCP-007ACC?logo=visualstudiocode&logoColor=white" alt="Install Topos MCP in VS Code"></a>
  <a href="https://pypi.org/project/topos-mcp/"><img src="https://img.shields.io/pypi/v/topos-mcp?color=3776AB&logo=python&logoColor=ffd43b" alt="PyPI"></a>
  <a href="https://github.com/Krv-Labs/topos/blob/main/LICENSE"><img src="https://img.shields.io/github/license/Krv-Labs/topos" alt="License"></a>
  <a href="https://glama.ai/mcp/servers/Krv-Labs/topos"><img src="https://glama.ai/mcp/servers/Krv-Labs/topos/badges/score.svg" alt="Topos MCP server"></a>
  <a href="https://clawhub.ai/krv-labs/skills/topos"><img src="https://img.shields.io/badge/%F0%9F%A6%9E_ClawHub-topos-F97316" alt="ClawHub"></a>
</p>
<!-- mcp-name: io.github.Krv-Labs/topos -->

<p align="center">
  <a href="#install-and-quick-start">Install</a> ·
  <a href="#what-topos-checks">What it checks</a> ·
  <a href="#under-the-hood">Under the hood</a> ·
  <a href="https://docs.krv.ai/topos/">Docs</a> ·
  <a href="https://github.com/Krv-Labs/topos/issues">Issues</a>
</p>

---

<!--
DEMO STUB — replace this comment only after recording the real release flow.

Show, in under 20 seconds:
1. an agent evaluates a repository;
2. Topos identifies the exact failing pillar and source hotspot;
3. the agent makes one focused refactor;
4. Topos verifies the medal improvement while the project tests stay green.

Prefer a checked-in, captioned GIF or SVG terminal recording with a stable
repository-relative URL. Do not publish a synthetic or hand-written result.
-->

<!--
STUDY STUB — keep hidden until the study, raw results, pinned repository SHAs,
and reproduction method are public.

Candidate headline:
"We evaluated <N> public repositories at pinned commits. <result>."

Required link target: a durable methodology/results page containing the corpus
selection rule, Topos version and configuration, machine details, raw JSON,
known limitations, and a reproduction command. Avoid labeling repositories as
"AI-generated" unless that provenance is explicit and independently verifiable.
-->

## Why Topos

Coding agents produce working code quickly. The harder question is whether the result is still easy to understand, safe to change, and well-fitted to the rest of the repository. **[Quality is the new currency.](https://krv.ai/field-notes/evaluating-code-generation)**

Topos computes that signal from program structure—not from an LLM review or a style opinion—and returns concrete failure locations and next actions. It is fast enough to sit inside the agent loop: measure, edit, verify, repeat.

**Tests check behavior. Topos checks whether the implementation is built to keep changing.**

> Grounded in category theory, written in Rust.

## Install and Quick Start

One binary. Every supported agent harness. A clean way back out.

### 1. Install the CLI

Use the verified release installer:

```bash
curl -fsSL https://docs.krv.ai/topos/install.sh | bash
```

Or install with Homebrew:

```bash
brew install krv-labs/tap/topos
```

On Homebrew 6+, that fully qualified one-liner auto-taps and trusts only this formula. If you `brew tap krv-labs/tap` first, run `brew trust --formula krv-labs/tap/topos` before `brew install topos`.

> [!TIP]
> **Prefer an editor-managed install?** In VS Code or Cursor, search `@mcp topos` in the Extensions view or choose [Install MCP server](https://github.com/mcp/Krv-Labs/topos). This is an alternative to `topos install`: your editor installs and manages the Topos MCP server for you.

### 2. Connect your coding agents

`topos install` detects every supported MCP harness and lets you configure any—or all—of them from one interactive checklist:

```bash
topos install
```

```text
┌  Which agent integrations do you want to configure?
│
│  ↑↓ move · space toggle · a all · enter confirm · esc cancel
│
│ ❯ ○ Claude Code          (detected)
│   ○ Claude Desktop       (detected)
│   ● Codex CLI            (✓ active)
│   ● Gemini CLI           (✓ active)
│   ○ GitHub Copilot CLI   (detected)
│   ○ Cursor               (detected)
│   ○ VS Code              (detected)
│   ○ Google Antigravity   (detected)
│   ○ pi                   (detected)
│   ○ OpenCode             (detected)
└
```

Restart the agents you configured, then ask:

> *"Use Topos to find this repository's worst structural problem, make one focused improvement, and verify the result."*


> [!IMPORTANT]
> Too many tools spray MCP servers across agent JSON files, scatter symlinks around your machine, then leave you to burn half a Claude session untangling the mess—or pull your own hair out doing it. Topos does not play that game. We follow a leave-no-trace policy: `topos status` shows every registration, while **`topos uninstall` opens the same selector, previews exactly what will change, and removes everything Topos installed.** If Topos makes it easy to do, it should be just as easy to undo.
>
> ```bash
> topos status
> topos uninstall
> ```


See the [agent setup guide](https://docs.krv.ai/topos/agents.html) for permissions, manual configuration, and troubleshooting.

### 3. Evaluate from the terminal

```bash
topos evaluate . -r
```

Topos discovers Python, Rust, JavaScript, TypeScript, C++, and Go automatically. Pass `--language` only when you want to narrow the run.

Reviewing a pull request instead? `topos pr-recap 5` gives a structural before/after card for the PR's changed files — no LLM, fully reproducible.

See [Installation](https://docs.krv.ai/topos/installation.html) for platform support and alternative install paths.


## What Topos checks

Every file gets four independent verdicts:

- **SIMPLE** — avoids unnecessary complexity using AST entropy and control-flow complexity.
- **COMPOSABLE** — limits a file's outward dependency burden; broader coupling and stability metrics remain available for diagnosis.
- **SECURE** — avoids dangerous API reachability and taint paths in the code property graph.
- **NAVIGABLE** — stays shallow enough for an agent to read and change in one pass, using depth-weighted nesting divergence over the AST scope tree.

Those verdicts roll up into one memorable quality medal without hiding which pillar failed:

| Medal | Criteria |
| :--- | :--- |
| 🏆 **PLATINUM** | Passes all 4 |
| 🥇 **GOLD** | Passes 3 of 4 |
| 🥈 **SILVER** | Passes 2 of 4 |
| 🥉 **BRONZE** | Passes 1 of 4 |
| ❌ **SLOP** | Passes 0, or fails to parse |


See the [full metrics reference](topos/mcp/docs/content/metrics.md). Refactor guidance also surfaces control-flow cycles, load-bearing dependency edges, and process bottlenecks.

<details>
<summary>How the medal system is derived</summary>

The four pillars are pairwise incomparable and form a sixteen-element evaluation lattice (a 4-cube); PLATINUM is their intersection. Labels below abbreviate the pillars as **S**imple, **C**omposable, **Sc** = Secure, **N**avigable.

<p align="center">
  <picture>
    <source media="(prefers-color-scheme: dark)" srcset="https://raw.githubusercontent.com/Krv-Labs/topos/main/docs/source/_static/figures/topos-lattice-dark.svg">
    <source media="(prefers-color-scheme: light)" srcset="https://raw.githubusercontent.com/Krv-Labs/topos/main/docs/source/_static/figures/topos-lattice.svg">
    <img src="https://raw.githubusercontent.com/Krv-Labs/topos/main/docs/source/_static/figures/topos-lattice.svg" alt="The full evaluation lattice — SLOP at the bottom, four single-pillar BRONZE states, six two-pillar SILVER states, four three-pillar GOLD states, and IDEAL (PLATINUM) at the top." width="900">
  </picture>
</p>

[Measures](https://docs.krv.ai/topos/measures.html) · [Category-theory foundations](https://docs.krv.ai/topos/concepts.html)

</details>




## Under the hood

Topos is a self-contained Rust CLI and MCP server. Analysis runs locally; your source code is not sent to an external model or hosted analysis service.

| Component | Role |
| :--- | :--- |
| [tree-sitter](https://tree-sitter.github.io/tree-sitter/) | Parses six languages and powers the native AST, CFG, CPG, PDG, and UAST representations. |
| [GitNexus](https://github.com/abhigyanpatwari/GitNexus) | Supplies the repository dependency graph scored by COMPOSABLE (`topos depgraph generate`). Requires `npm install -g gitnexus@1.6.8`. |
| [Sighthound](https://github.com/Corgea/Sighthound) | Embedded in the MCP server for supplementary security findings; native CPG probes remain the SECURE scoring source. |

The result is one agent-facing contract over several structural lenses: one score to optimize, explicit evidence for each failure, and a verification loop that can tell a real improvement from cosmetic churn.


## More ways to use Topos

- **OpenClaw / ClawHub:** [`openclaw skills install @Krv-Labs/topos`](https://clawhub.ai/krv-labs/skills/topos)
- **Hermes:** `hermes skills tap add Krv-Labs/topos` then `hermes skills install Krv-Labs/topos/topos`
- **Agent Plugins:** point a [compatib