Sieve MCP Server — AI-Powered Venture Capital Due Diligence
The first MCP server purpose-built for venture capital. Drop a company name into Claude, Cursor, or Windsurf and get a quantified investment memo in 5 minutes — not a ChatGPT summary, a real analyst-grade IMPACT-X assessment with every claim verified against evidence.
"Screen a startup called Acme Corp" → Sieve researches the company, scores it across 7 dimensions, verifies every claim, and tells you: Take the meeting or Pass.
Why Sieve?
Most VCs screen 50+ deals a month. Most of those are obvious passes — but you still spend 2-3 hours per deal on basic diligence before you know that. Sieve does that work in 5 minutes.
What You Get
| Capability | Details |
|---|---|
| Investment Memo | Full analyst-grade memo with executive summary, key strengths, critical concerns, and actionable recommendation — not a ChatGPT summary |
| Deal Scoring (0-140) | Quantified Sieve Score across 7 IMPACT-X dimensions — structured, repeatable, comparable across your portfolio |
| Red Flag Detection | Automatically surfaces deal-breakers: founder risk, market timing issues, unsustainable unit economics, missing traction, competitive threats |
| Evidence Verification | Every finding tagged as Documented, Discovered, Inferred, or Missing — cross-references pitch deck claims against real-world evidence |
| Competitive Landscape | Maps competitors, identifies moat strength, evaluates defensibility and switching costs |
| Financial Model Assessment | Evaluates unit economics, pricing power, revenue model viability, and path to profitability |
| Market Sizing | TAM/SAM/SOM analysis with timing assessment — is the market ready? |
| Team Evaluation | Founder-market fit, team completeness, domain expertise, execution track record |
| Traction Analysis | Growth metrics, customer validation, revenue signals, engagement patterns |
| Real-time Deal Chat | Ask follow-up questions, challenge findings, explore what-if scenarios, dig into any dimension |
| Sector-Aware Analysis | Adapts benchmarks for fintech, healthtech, deeptech, climate, SaaS, consumer, and more |
| Stage-Calibrated | Different expectations for pre-seed vs seed vs Series A — doesn't penalize early-stage for missing late-stage metrics |
What Makes Sieve Different
- Not a wrapper around ChatGPT. Sieve runs a structured multi-agent analysis pipeline with real-time web research, evidence verification, and domain-specific benchmarks.
- We tell you what we don't know. Every finding is evidence-typed (Documented / Discovered / Inferred / Missing) so you see exactly what's verified and where the gaps are.
- Repeatable framework. The same IMPACT-X methodology every time, so you can compare deals apples-to-apples across your portfolio.
- Built by VCs. Not a generic AI tool adapted for investing — purpose-built for the way investors actually evaluate deals.
IMPACT-X Framework
| Dimension | What Sieve evaluates |
|---|---|
| I — Innovators | Founding team quality, experience, domain expertise |
| M — Market | Opportunity size, timing, tailwinds |
| P — Product | Solution strength, differentiation, technical depth |
| A — Advantage | Competitive moat, defensibility, switching costs |
| C — Commerce | Business model, unit economics, pricing power |
| T — Traction | Growth metrics, validation signals, customer evidence |
| X — X-Factor | Unique qualities, timing advantages, intangibles |
Each dimension scores 0-20. Total Sieve Score ranges from 0-140.
Quick Start
Install
pip install sieve-mcp
Or run directly without installing:
uvx sieve-mcp
Get Your API Key
- Sign up free at app.sieve.arceusxventures.com
- Go to Settings → copy your API key
- Free tier: 2 screens/month. Pro: unlimited.
Claude Desktop
Add to your claude_desktop_config.json:
{
"mcpServers": {
"sieve": {
"command": "uvx",
"args": ["sieve-mcp"],
"env": {
"SIEVE_API_KEY": "your-api-key"
}
}
}
}
Claude Code
claude mcp add sieve -- uvx sieve-mcp
export SIEVE_API_KEY="your-api-key"
Cursor / Windsurf
Add to your MCP settings:
{
"mcpServers": {
"sieve": {
"command": "uvx",
"args": ["sieve-mcp"],
"env": {
"SIEVE_API_KEY": "your-api-key"
}
}
}
}
Available Tools
| Tool | What it does | Read-only |
|---|---|---|
sieve_screen | Start a Quick Screen — pass a company name, optional website URL, pitch deck text, or description | No |
sieve_status | Poll analysis progress — see which dimensions are complete and current scores | Yes |
sieve_summary | Get the full investment memo — Sieve Score, recommendation, strengths, concerns, evidence | Yes |
sieve_usage | Check how many screens you've used this billing period | Yes |
Example Workflow
Just talk to your AI assistant naturally:
1. Screen a startup
"Run a Sieve screen on Acme Corp at acme.com"
2. Check progress (analysis takes 2-5 minutes)
"What's the status of that Sieve analysis?"
3. Get the full investment memo
"Show me the Sieve results for Acme Corp"
4. Explore the deal
"What are the red flags? Anything that should kill this deal?"
"How strong is their competitive moat? Who are the main competitors?"
"Walk me through their unit economics — is this business model viable?"
"How does the founding team stack up? Any gaps?"
"What's the market timing like? Is this too early or too late?"
"Compare this deal to the last three I screened"
5. Check your usage
"How many Sieve screens do I have left this month?"
Pro tip: Upload a pitch deck for deeper analysis
Paste pitch deck text or founder meeting notes for maximum accuracy:
"Screen Acme Corp — here's their pitch deck text: [paste]. Also check acme.com"
Sieve cross-references every pitch deck claim against real-world evidence. When a founder says "fastest-growing in the category," Sieve checks if that's actually true.
More things you can ask
| Use case | Example prompt |
|---|---|
| Quick pass/take meeting | "Screen this company and give me the bottom line" |
| Investment memo for IC | "Generate a full investment memo I can present to my partners" |
| Red flag check | "What are the deal-breakers for this startup?" |
| Competitive analysis | "Who competes with this company and how defensible are they?" |
| Financial viability | "Does their business model make sense? What are the unit economics?" |
| Team assessment | "Evaluate the founding team — any gaps or concerns?" |
| Market validation | "Is the market real? What's the TAM and timing?" |
| Batch screening | "Screen these 5 startups and rank them by Sieve Score" |
| Follow-up prep | "Based on this analysis, what questions should I ask the founders?" |
| Portfolio comparison | "How does this deal compare to others I've screened?" |
Who Uses Sieve
- Solo GPs screening 50+ deals/month — stop spending hours on obvious passes
- Angel investors evaluating startups outside their domain — Sieve brings sector expertise
- Emerging fund managers building a repeatable diligence process — consistent framework, every time
- Accelerators standardizing evaluation — compare apples to apples across your cohort
Environment Variables
| Variable | Required | Default | Description |
|---|---|---|---|
SIEVE_API_KEY | Yes | — | Your Sieve API key (get one free) |
SIEVE_API_URL | No | https://api.sieve.arceusxventures.com | API base URL |
Running with Docker
docker build -t sieve-mcp .
docker run -p 8080:8080 -e SIEVE_API_KEY=your-key sieve-mcp
Development
# Install locally
pip install -e .
# Run in stdio mode (for MCP clients)
sieve-mcp
# Run in HTTP mode (for remote/container deployment)
sieve-mcp http
Also Available As
Sieve isn't just an MCP server. Use it however fits your workflow:
- Web App — app.sieve.arceusxventures.com — Full experience with real-time deal chat and document upload
- REST API — api.sieve.arceusxventures.com/api/docs — Integrate into custom deal flow pipelines
- Android App — Screen startups on the go
Links
- Website: sieve.arceusxventures.com
- Web App: app.sieve.arceusxventures.com
- API Docs: api.sieve.arceusxventures.com/api/docs
- PyPI: pypi.org/project/sieve-mcp
- Contact: hello@arceusxventures.com
License
MIT
Built by ArceusX Ventures — from VCs, for VCs.
<!-- mcp-name: io.github.lmwharton/sieve-mcp -->