io.github.bluwork/kontra-mcp

Kontra

The Tenth Man Protocol

"If nine agree, I disagree."

An MCP tool that stress-tests your decisions with structured contrarian analysis — so blind spots surface before consequences do.

What You Get

You say:

"Use kontra to challenge this: We should rewrite our backend from Node.js to Rust. Context: Current stack is Node.js, team of 3, shipping weekly."

Kontra returns:

BLIND SPOTS

• You're measuring the cost of rewriting but not the cost of pausing. A team of 3 shipping weekly has momentum. The rewrite doesn't just cost engineering hours — it costs 3-6 months of feature development, customer feedback loops, and market positioning that your competitors won't pause for.

• Rust's safety guarantees solve problems you may not have. If your Node.js backend isn't failing due to memory bugs or concurrency issues, you're optimizing for a class of problems that isn't hurting you. The rewrite is a solution — what's the problem it solves that your team is actually experiencing?

• The team's Rust proficiency is unproven at production scale. Writing Rust that compiles is not the same as writing Rust that ships. Borrow checker fluency, async runtime decisions (Tokio vs. async-std), ecosystem maturity for your specific domain — these are all unknowns that compound under deadline pressure.

HIDDEN ASSUMPTIONS

...

THE STRONGEST COUNTER-ARGUMENT

...

WHAT-IF SCENARIOS

...

That's counter mode — the default. There are three more.

Quick Start

Claude Code

claude mcp add kontra -- npx -y kontra-mcp

Then ask: "Use kontra to analyze my decision to..."

{
  "mcpServers": {
    "kontra": {
      "command": "npx",
      "args": ["-y", "kontra-mcp"]
    }
  }
}

{
  "kontra": {
    "command": "npx",
    "args": ["-y", "kontra-mcp"]
  }
}

Modes

counter — The Tenth Man

"Consensus is never to be mistaken for correctness."

The default. Assumes your decision is wrong and builds the strongest possible case against it.

Produces: Blind Spots, Hidden Assumptions, The Strongest Counter-Argument, What-If Scenarios

Best for: Major decisions where you need someone to steelman the opposing side. Architecture choices, strategy pivots, hiring plans, product bets.

probe — The Interrogator

"A good question does more damage to a bad decision than any argument ever could."

Asks 7-10 pointed questions across five lenses — no answers, no analysis, just the questions you haven't asked yourself.

Produces: Questions across Motivation, Evidence, Alternatives, Stakes, and Timing

Best for: Early-stage decisions where you suspect your reasoning has gaps but aren't sure where. Forces you to confront what you've skipped over.

redteam — The Red Team Commander

"Think like an adversary — not a hypothetical one, but a specific, intelligent opponent who wants this decision to fail."

Constructs 3-5 concrete failure scenarios with likelihood ratings, trigger events, cascade sequences, early warning signs, and mitigations.

Produces: Ranked failure scenarios with likelihood estimates, plus an Overall Vulnerability Assessment (1-10 scale)

Best for: Plans that are already in motion. Launch timelines, migration strategies, organizational changes — anything where you need to know exactly how it breaks.

premortem — The Postmortem From the Future

"Prospective hindsight increases the ability to identify reasons for future outcomes by 30%."

Imagines the decision was made 12 months ago and failed catastrophically. Writes the full postmortem.

Produces: Executive Summary, What Happened (Failure Narrative), Timeline, Root Causes, Signals We Missed, Lessons Learned

Best for: High-stakes, hard-to-reverse decisions. Useful when the team is confident and you need to break the spell of inevitability.

Usage

Counter a strategy decision:

"Use kontra to challenge this: We're going all-in on AI agents for our product roadmap."

Probe a career move:

"Use kontra in probe mode to question my decision to leave my job and start a SaaS company. Context: I have 8 months of runway, no co-founder, and a B2B idea with 3 LOIs."

Red team a launch plan:

"Use kontra in redteam mode against our plan to launch in 6 weeks. Context: We have no staging environment, 40% test coverage, and one DevOps engineer."

Pre-mortem a hiring decision:

"Use kontra in premortem mode on: We're hiring 5 junior engineers instead of 2 seniors. Context: Current team is 4 seniors, shipping velocity is the bottleneck."

Tool Parameters

What This Is NOT

• Not a pros-and-cons generator. Kontra doesn't weigh both sides. It attacks one side — yours — with full force.
• Not a risk assessment framework. No probability matrices or color-coded dashboards. Structured argumentation, not bureaucratic process.
• Not a generic "be careful" warning. Every output is specific to your decision and context. No boilerplate applies-to-anything advice.
• Not a replacement for human judgment. Kontra surfaces what you might miss. You still decide.

How It Works

Kontra uses the prompt-return pattern. When called, it constructs a carefully engineered adversarial prompt and returns it as the tool response. Your MCP client's own LLM processes the prompt and produces the analysis.

• No API keys needed — uses your client's existing LLM
• No additional network calls — prompt is returned, not executed
• Works with any MCP client — Claude Desktop, Claude Code, Cursor, VS Code

Analysis quality scales with model capability. Stronger models produce sharper, more specific contrarian analysis.

Configuration

License

Apache-2.0