crucible-mcp 0.4.0

Code review MCP server for Claude. Not affiliated with Atlassian.

Crucible

Your team's standards, applied by Claude, every time.

Claude without context applies generic best practices. Crucible loads your patterns—so Claude reviews code the way your team would, not the way the internet would.

├── Personas:      Domain-specific thinking (how to approach problems)
├── Knowledge:     Coding patterns and principles (what to apply)
├── Cascade:       Project → User → Bundled (customizable at every level)
└── Context-aware: Loads relevant skills based on what you're working on

Why Crucible?

• Consistency — Same checklist every time, for every engineer, every session
• Automation — Runs in CI and pre-commit, not just interactively
• Institutional knowledge — Your senior engineer's mental checklist, in the repo
• Your context — Security fundamentals plus your auth patterns, your conventions, your definition of "done"
• Cost efficiency — Filter with free tools first, LLM only on what needs judgment

Not affiliated with Atlassian's Crucible.

Install

pip install crucible-mcp

Add to Claude Code (.mcp.json):

{
  "mcpServers": {
    "crucible": {
      "command": "crucible-mcp"
    }
  }
}

With hot reload (recommended for customization):

{
  "mcpServers": {
    "crucible": {
      "command": "mcpmon",
      "args": ["--watch", "~/.crucible/", "--", "crucible-mcp"]
    }
  }
}

How It Works

Code → Detect Domain → Load Personas + Knowledge → Claude with YOUR patterns

.sol file → web3 domain → security-engineer + SMART_CONTRACT.md → Knows your security rules

MCP Tools

Tool	Purpose
review(path)	Full review: analysis + skills + knowledge
review(mode='staged')	Review git changes with skills + knowledge
load_knowledge(files)	Load specific knowledge files
get_principles(topic)	Load engineering knowledge by topic
delegate_*	Direct tool access (semgrep, ruff, slither, bandit)
check_tools()	Show installed analysis tools

The unified review tool supports:

• Path-based: review(path="src/") - analyze files/directories
• Git-aware: review(mode="staged") - analyze changes (staged, unstaged, branch, commits)
• Quick mode: review(path, include_skills=false) - analysis only, no skills/knowledge

CLI

crucible init                     # Initialize .crucible/ for your project
crucible review                   # Review staged changes
crucible review --mode branch     # Review current branch vs main
crucible ci generate              # Generate GitHub Actions workflow

crucible skills list              # List all skills
crucible skills init <skill>      # Copy to .crucible/ for customization

crucible knowledge list           # List all knowledge files
crucible knowledge init <file>    # Copy for customization

crucible hooks install            # Install pre-commit hook

See ARCHITECTURE.md for the full flow.

Customization

Override skills and knowledge for your project or personal preferences:

# Customize a skill for your project
crucible skills init security-engineer
# Creates .crucible/skills/security-engineer/SKILL.md

# Add project-specific concerns, team conventions, etc.

Resolution order (first found wins):

1. .crucible/ — Project overrides
2. ~/.claude/crucible/ — User preferences
3. Bundled — Package defaults

See CUSTOMIZATION.md for the full guide.

What's Included

18 Personas — Domain-specific thinking: security, performance, accessibility, web3, backend, and more.

See SKILLS.md for the full list.

12 Knowledge Files — Coding patterns and principles for security, testing, APIs, databases, smart contracts, etc.

See KNOWLEDGE.md for topics covered.

Documentation

Doc	What's In It
FEATURES.md	Complete feature reference
ARCHITECTURE.md	How MCP, tools, skills, and knowledge fit together
CUSTOMIZATION.md	Override skills and knowledge for your project
SKILLS.md	All 18 personas with triggers and focus areas
KNOWLEDGE.md	All 12 knowledge files with topics covered
CONTRIBUTING.md	Adding tools, skills, and knowledge

Development

pip install -e ".[dev]"
pytest                    # Run tests (509 tests)
ruff check src/ --fix     # Lint