mcp-builder vs Agent Arena
mcp-builder is a plugin bundle for AI coding tools published by Composio. Marketplaces we read that list it: 1 (Community GitHub marketplaces). Agent Arena is an MCP server published by agentarenaleague. Marketplaces we read that list it: 1 (Official MCP Registry). As of our marketplace pass on 2026-10-28. 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 |  Agent Arena | |
|---|---|---|
| Community marketplace composio-community/awesome-claude-plugins | Listed Version: not stated Forks (GitHub): 716 Stars (GitHub): 1 966 Not marked · First seen |
Not listed |
| Official MCP Registry | Not listed | Listed Version: 1.0.1 Forks (GitHub): 0 Stars (GitHub): 0 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 | mcp-builder | Agent Arena |
|---|---|---|
| Marketplaces that list it | 1 | 1 |
| Stars (GitHub) (differs) | 1 966 (better) | 0 (worse) |
| Forks (GitHub) (differs) | 716 (better) | 0 (worse) |
| Last release (differs) | Not published | 2026-10-19 |
| Where it runs (differs) | Installs as a plugin bundle | Remote server (agentarenaleague.pages.dev/mcp) |
| Transport (differs) | Not stated | Streamable HTTP |
| Tools it declares | Not published | Not published |
| Environment variables it asks for | Not published | Not published |
| Parts of the bundle (differs) | 1 | Not a bundle |
| Licence | Not stated | Not stated |
| Repository (differs) | github.com/composio-community/awesome-claude-plugins | github.com/agentarenaleague/agent-arena |
| Changes in the last 7 days | 0 | 0 |
| First seen | 2026-10-15 | 2026-10-15 |
| Endpoint at the last check (differs) | no remote endpoint we check | Responded 39 h ago |
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
mcp-builder
Build high-quality MCP servers for LLM integrations
Agent Arena
Paper trading only. 26 leagues for AI bots. Spot Crypto + Crypto 35 live. Register by MCP.
How to run each
mcp-builder As a Claude Code plugin
/plugin marketplace add composio-community/awesome-claude-plugins
/plugin install mcp-builder@awesome-claude-pluginsAgent Arena As a remote MCP server
claude mcp add --transport http agent-arena https://agentarenaleague.pages.dev/mcpCommands built only from what the marketplaces declare; the full set for every client is on each card.
Only Agent Arena has a remote endpoint we check. How we check endpoints
Tools each declares
Neither the marketplaces of mcp-builder nor its endpoint list any tools, so we do not compare tools.
Settings each asks for
Neither one's marketplaces publish the settings it asks for.
What it can do: mcp-builder · What it can do: Agent Arena · Compare two other plugins
Data comes from public marketplace files in GitHub repositories of their authors. Data comes from the Official MCP Registry (registry.modelcontextprotocol.io), CC0 1.0. Figures come from our own regular passes over the marketplaces, last read on . We publish no contact details for plugin publishers.