harness-evolver vs Opik
harness-evolver is a plugin bundle for AI coding tools published by raphaelchristi. Marketplaces we read that list it: 1 (Claude Code: claude-plugins-community). Opik is an MCP server published by comet-ml. Marketplaces we read that list it: 2 (Official MCP Registry, Docker MCP Catalog). As of our marketplace pass on 2026-10-15. This pair was picked by a reader, not by our comparison rule, so search engines are asked not to index the page.
Where each is published
| Marketplace |  harness-evolver |  Opik |
|---|---|---|
| Claude Code: claude-plugins-community | Listed Version: 6.4.2 Forks (GitHub): 6 Stars (GitHub): 56 Not marked · First seen |
Not listed |
| Official MCP Registry | Not listed | Listed Version: 3.0.5 Downloads/month (PyPI): 3 591 Downloads/week (PyPI): 1 906 Forks (GitHub): 38 Stars (GitHub): 222 Not marked · First seen |
| Docker MCP Catalog | Not listed | Listed Version: sha256:0e0d7d33d5eb Forks (GitHub): 38 Pulls (Docker Hub): 16 951 Stars (Docker Hub): 1 Stars (GitHub): 222 Not marked · First seen |
Each figure is the marketplace's own and is never added up across marketplaces. A marketplace that publishes no figure shows none: no number is not zero.
The facts side by side
| Fact | harness-evolver | Opik |
|---|---|---|
| Marketplaces that list it (differs) | 1 (worse) | 2 (better) |
| Stars (GitHub) (differs) | 56 (worse) | 222 (better) |
| Pulls (Docker Hub) (differs) | No figure on Docker Hub | 16 951 |
| Forks (GitHub) (differs) | 6 (worse) | 38 (better) |
| Last release | Not published | Not published |
| Where it runs (differs) | Installs as a plugin bundle | Remote server or your machine |
| Transport (differs) | Not stated | Streamable HTTP, stdio |
| Tools it declares (differs) | Not published | 13 |
| Environment variables it asks for (differs) | Not published | 4, secrets among them: 1 |
| Hooks it runs (differs) | 1 | Not published |
| Parts of the bundle (differs) | 13 | Not a bundle |
| Licence (differs) | MIT | Apache-2.0 |
| Repository (differs) | github.com/raphaelchristi/harness-evolver | github.com/comet-ml/opik-mcp |
| Changes in the last 7 days | 0 | 0 |
| First seen | 2026-10-11 | 2026-10-11 |
| Endpoint at the last check (differs) | no remote endpoint we check | not checked yet |
Lines where the two differ have a tinted background and bold values. Where the data itself says which value is better (more marketplaces, a larger figure of the same marketplace, a fresher release, a verified mark on a marketplace that lists both), the better one is also marked green with ▲ and the worse one red with ▼. Where it runs, the transport, the tools, the settings, hooks, the bundle's parts, the licence and the week's changes are marked only as different: more or fewer is not better in itself.
What each says it does
harness-evolver
Autonomous LLM agent optimization using LangSmith. Spawns 5 parallel proposers in git worktrees, evaluates candidates via LangSmith experiments, and merges winners automatically. Includes evaluator agent (LLM-as-judge via langsmith-cli), critic, architect, and testgen agents. No external API keys needed beyond LangSmith.
Opik
Read and score Opik traces, experiments, datasets and prompts from your AI assistant.
How to run each
harness-evolver As a Claude Code plugin
/plugin marketplace add anthropics/claude-plugins-community
/plugin install harness-evolver@claude-communityOpik As a remote MCP server
claude mcp add --transport http opik-mcp https://www.comet.com/opik/api/v1/mcpRequires: OPIK_API_KEY (secret)
Commands built only from what the marketplaces declare; the full set for every client is on each card.
Tools each declares
The marketplaces of harness-evolver publish no list of tools, so we do not compare tools.
Settings each asks for
The marketplaces of harness-evolver publish no settings it asks for, so we do not compare settings.
What it can do: harness-evolver · What it can do: Opik · Compare two other plugins
Data comes from the public marketplace file https://github.com/anthropics/claude-plugins-community/blob/HEAD/.claude-plugin/marketplace.json. Data comes from the Official MCP Registry (registry.modelcontextprotocol.io), CC0 1.0. Data comes from the Docker MCP Catalog (desktop.docker.com/mcp/catalog) and Docker Hub. Figures come from our own regular passes over the marketplaces, last read on . We publish no contact details for plugin publishers.