The consent screen shows an error

Try again in a fresh private browsing window. If the error persists, contact support at cromus.ai/contact.

Cromus does not appear in my client's tool list

Disconnect and reconnect the connector, then start a new conversation.

Authorization window never opens

Check that pop-ups are allowed for your AI client.

Which plans support connectors?

Connectors require a paid plan on most clients. Cromus itself does not charge for connecting.

Connect to the Cromus MCP Server

Cromus is a remote MCP server hosted at https://mcp.cromus.ai/mcp. Nothing needs to be downloaded or installed. Connect once using OAuth 2.1 with PKCE, then score and validate skills from inside Claude or any MCP-compatible AI client.

The server exposes nine deterministic tools: score_skill (0 to 1000 Croms score with four-dimension breakdown), simulate_cost (per-run and monthly cost across five routing modes), check_mcp_drift (compares declared MCP dependencies against a live server and flags schema changes, missing tools, and new tools), validate_skill (SKILL.md conformance check), validate_mcp_deps (checks a skill's mcp_dependencies block for completeness, valid transports, auth declarations, and fallback behavior), validate_ethos (ETHOS.md governance check), validate_memory (MEMORY.md handoff check), reality_check_summary (most recent Reality Check for a skill, read-only), and check_usage_waste (analyzes AI API usage exports for waste patterns including low cache utilization, verbose output ratios, premium model concentration, spend acceleration, model sprawl, and idle burn).

Claude users can connect from the directory (Settings, Connectors, search Cromus) or by adding a custom connector with the server URL. Claude Code users run one terminal command and approve access in a browser window. Any other client that supports remote MCP servers with OAuth can connect using a standard mcpServers configuration block.

Cromus does not charge for connecting. The connector is available on paid Claude plans.