mcp-pricing 2.1.0

Enterprise pricing engine MCP server — CEL rule engine, price waterfall, catalog, segments, promotions, quotes, market intel, audit (35+ tools)
Documentation

Pricing Engine MCP Server

Crates.io Docs.rs License ADK-Rust Enterprise Registry Ready

Enterprise pricing engine for ADK-Rust Enterprise agents. Provides 21 MCP tools covering the full pricing lifecycle — CEL rule engine, price waterfall, product catalog, customer segments, promotions, quotes/CPQ, market intelligence, and audit trail. Vertical-agnostic: works for ride-hailing, SaaS, e-commerce, logistics, marketplaces, and professional services.

Architecture

┌─────────────────────────────────────────────────────────────────────┐
│                     MCP Transport (stdio)                            │
├─────────────────────────────────────────────────────────────────────┤
│                    Tool Router (21 tools)                            │
├──────────┬──────────┬──────────┬──────────────┬─────────────────────┤
│  Price   │   Rule   │ Catalog  │  Promotions  │   Market Intel      │
│  Calc    │  Engine  │  & SKUs  │  & Quotes    │   & Audit           │
├──────────┴──────────┴──────────┴──────────────┴─────────────────────┤
│                     CEL Evaluation Layer                             │
│         Common Expression Language (cel-interpreter)                 │
├─────────────────────────────────────────────────────────────────────┤
│                     In-Memory Data Store                             │
│   Products · Rules · Segments · Promotions · Quotes · Audit Log     │
└─────────────────────────────────────────────────────────────────────┘

Key Principles

  • CEL-powered rules — pricing rules use Common Expression Language for type-safe, auditable conditions.
  • Price waterfall — deterministic 6-step pipeline: list → segment → promotions → rules → floor/ceiling → tax.
  • Explain mode — every price calculation can return the full waterfall breakdown showing which rule caused each price movement.
  • Vertical-agnostic — same engine prices rides, SaaS subscriptions, physical goods, API calls, and professional services.
  • Audit everything — every rule change, product update, and quote approval is logged immutably.
  • Zero configuration — starts with no external dependencies. Market intel (FX rates) works immediately via free APIs.

Tools (21)

Price Calculation

Tool Description Annotations
price_calculate Calculate price through full waterfall with CEL rules. Set explain=true for step-by-step breakdown. read-only, idempotent

Rule Engine

Tool Description Annotations
rules_create Create a pricing rule with CEL condition and actions write
rules_list List all pricing rules read-only
rules_activate Activate a rule (starts affecting prices) write
rules_deactivate Deactivate a rule (stops affecting prices) write
rules_validate Validate a CEL expression without saving read-only

Product Catalog

Tool Description Annotations
catalog_upsert Add or update a product (SKU, name, price, cost) write
catalog_get Get product details by SKU read-only
catalog_list List all products in catalog read-only

Customer Segments

Tool Description Annotations
segments_create Create a segment with CEL condition and default discount write
segments_list List all customer segments read-only

Promotions

Tool Description Annotations
promotions_create Create a promotion (coupon, volume tier, BOGO, flash sale) write
promotions_list List all promotions read-only
promotions_apply Apply a promo code to a SKU and get discounted price read-only

Quotes / CPQ

Tool Description Annotations
quotes_create Create a quote with locked prices for a customer write
quotes_get Get quote by ID read-only
quotes_approve Approve a quote (requires approval gate) write

Market Intelligence

Tool Description Annotations
market_fx_convert Convert between 170+ currencies (live rates) read-only
market_fx_rates Get FX rates for multiple currencies read-only
market_tax Calculate VAT/GST/sales tax by country (50+ countries) read-only

Audit

Tool Description Annotations
audit_log Query the immutable audit trail read-only

Installation

From crates.io

cargo install mcp-pricing

Build from source

git clone https://github.com/zavora-ai/mcp-pricing
cd mcp-pricing
cargo build --release

Claude Desktop

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

Kiro

Add to .kiro/settings/mcp.json:

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

Cursor

Add to .cursor/mcp.json:

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

Windsurf / Codex / Open Code

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

Price Waterfall

Every call to price_calculate traverses a deterministic waterfall:

1. List price (from catalog)
2. Segment discount (customer segment override)
3. Promotions (active promos matching CEL conditions)
4. Pricing rules (CEL-based, sorted by priority)
5. Floor/ceiling guards (prevent below-floor or above-ceiling)
6. Tax calculation (VAT/GST by country)
─────────────────────────────────────────────────────────────
→ Net price returned

When explain: true, the full waterfall is returned:

{
  "waterfall": [
    { "step": "list", "price_before": 500.0, "price_after": 500.0, "reason": "Base list price" },
    { "step": "rule", "price_before": 500.0, "price_after": 425.0, "reason": "Rule: Volume discount 10+", "rule_id": "rule_bf5d0b54" },
    { "step": "tax", "price_before": 425.0, "price_after": 493.0, "reason": "Tax 16%" }
  ]
}

CEL Expression Language

Rules and segments use Common Expression Language (CEL) — the same language used by Kubernetes, Google Cloud IAM, and Firebase Security Rules.

Available Variables

Variable Type Description
item.sku string Product SKU being priced
item.quantity int Quantity in the line item
item.channel string Sales channel (direct, marketplace, partner)
customer.id string Customer identifier
customer.segment string Resolved segment name
customer.country string ISO 3166-1 alpha-2
customer.annual_spend int Lifetime spend
catalog.list_price int Current list price
catalog.cost int Cost of goods
catalog.category string Product category

Example Conditions

# Volume discount: 15% off for orders of 10+
item.quantity >= 10

# Enterprise segment pricing
customer.segment == "enterprise" && item.channel == "direct"

# Regional pricing for East Africa
customer.country in ["KE", "TZ", "UG", "RW"]

# Category-specific rule
catalog.category == "SaaS" && customer.annual_spend > 100000

# Channel-specific markup
item.channel == "marketplace"

Rule Actions

Action Type Effect Example
pct_discount Reduce price by N% {"type": "pct_discount", "value": 15}
absolute_discount Reduce price by fixed amount {"type": "absolute_discount", "value": 50}
markup_pct Increase price by N% {"type": "markup_pct", "value": 20}
set_price Override to fixed price {"type": "set_price", "value": 999}
multiply_price Multiply price (surge) {"type": "multiply_price", "value": 1.5}
set_floor Set minimum price guard {"type": "set_floor", "value": 100}
set_ceiling Set maximum price guard {"type": "set_ceiling", "value": 5000}

Quick Start

1. Add a product

{
  "name": "catalog_upsert",
  "arguments": {
    "sku": "RIDE-STD",
    "name": "Standard Ride",
    "category": "transport",
    "list_price": 500,
    "cost": 200,
    "currency": "KES"
  }
}

2. Create a pricing rule

{
  "name": "rules_create",
  "arguments": {
    "name": "Volume discount 10+",
    "condition": "item.quantity >= 10",
    "actions": [{"type": "pct_discount", "value": 15}],
    "active": true
  }
}

3. Calculate price with waterfall

{
  "name": "price_calculate",
  "arguments": {
    "sku": "RIDE-STD",
    "quantity": 12,
    "country": "KE",
    "explain": true
  }
}

Response:

{
  "sku": "RIDE-STD",
  "quantity": 12,
  "list_price": 500.0,
  "net_price": 425.0,
  "line_total": 5100.0,
  "tax_amount": 816.0,
  "total": 5916.0,
  "currency": "KES",
  "tax_rate_pct": 16.0,
  "waterfall": [
    { "step": "list", "price_before": 500.0, "price_after": 500.0, "reason": "Base list price" },
    { "step": "rule", "price_before": 500.0, "price_after": 425.0, "reason": "Rule: Volume discount 10+" },
    { "step": "tax", "price_before": 425.0, "price_after": 493.0, "reason": "Tax 16%" }
  ]
}

4. Create a promotion

{
  "name": "promotions_create",
  "arguments": {
    "name": "Launch 20% Off",
    "promo_type": "coupon",
    "code": "LAUNCH20",
    "discount_type": "pct",
    "discount_value": 20,
    "condition": "item.channel == \"direct\"",
    "max_uses": 1000,
    "stackable": false
  }
}

5. Generate a quote

{
  "name": "quotes_create",
  "arguments": {
    "customer_id": "cust_james",
    "items": [
      {"sku": "RIDE-STD", "quantity": 5},
      {"sku": "RIDE-PREMIUM", "quantity": 2}
    ],
    "currency": "KES",
    "valid_days": 14,
    "notes": "Corporate account pricing"
  }
}

6. Convert currency

{
  "name": "market_fx_convert",
  "arguments": { "amount": 5916, "from": "KES", "to": "USD" }
}

Tax Coverage (50+ Countries)

Region Countries Rate Range
East Africa KE (16%), TZ (18%), UG (18%), RW (18%), GH (15%) 15-18%
Southern Africa ZA (15%), NG (7.5%) 7.5-15%
Europe UK (20%), DE (19%), FR (20%), SE/NO/DK (25%), CH (8.1%) 8-27%
Americas US (0-8% by state), CA (5%), BR (17%), MX (16%) 0-17%
Asia-Pacific AU (10%), JP (10%), IN (18%), SG (9%), CN (13%) 9-18%
Middle East AE/SA (5%) 5%

Use Cases

Ride-Hailing / Mobility

catalog_upsert (RIDE-STD, RIDE-PREMIUM, RIDE-XL)
rules_create ("Surge 2x", "item.channel == 'peak'", multiply_price: 2.0)
rules_create ("Loyalty discount", "customer.annual_spend > 50000", pct_discount: 10)
price_calculate (sku, qty=1, channel="peak", country="KE")

SaaS Subscription

catalog_upsert (PLAN-STARTER: $29, PLAN-PRO: $99, PLAN-ENTERPRISE: $299)
segments_create ("Enterprise", "customer.annual_spend > 100000", discount: 25%)
rules_create ("Annual billing", "item.channel == 'annual'", pct_discount: 20)
quotes_create (customer, items=[{sku: "PLAN-PRO", qty: 50}])

E-Commerce

catalog_upsert (SKU-WIDGET-A: $49.99, cost: $15)
promotions_create ("SUMMER25", pct, 25%, condition: "catalog.category == 'outdoor'")
rules_create ("Wholesale", "item.quantity >= 100", pct_discount: 40)
price_calculate (sku, qty=150, explain=true)

Marketplace / Multi-Vendor

rules_create ("Marketplace fee", "item.channel == 'marketplace'", markup_pct: 15)
rules_create ("Floor guard", condition: "true", set_floor: cost * 1.1)
price_calculate (sku, channel="marketplace")

Professional Services

catalog_upsert (CONSULT-HR: $200/hr, CONSULT-LEGAL: $350/hr)
segments_create ("Non-profit", "customer.segment == 'ngo'", discount: 30%)
quotes_create (customer, items=[{sku: "CONSULT-HR", qty: 40}], valid_days: 30)
quotes_approve (quote_id)

Configuration

Environment Variables

Variable Required Purpose
RUST_LOG No Log level (default: info)

No API keys needed. FX rates use the free open.er-api.com service. All other functionality is pure computation.

MCP Server Manifest

server_id = "mcp_pricing"
display_name = "Pricing Engine"
version = "2.0.0"
domain = "pricing"
risk_level = "medium"
writes_allowed = "gated"
governance_gates = ["audit_all_changes"]

Error Codes

Code Meaning
SKU_NOT_FOUND Product SKU not in catalog
RULE_NOT_FOUND Rule ID doesn't exist
CONDITION_PARSE_ERROR CEL expression failed to parse
QUOTE_NOT_FOUND Quote ID doesn't exist
PROMO_NOT_FOUND_OR_INACTIVE Promotion code invalid or expired
FX_RATE_UNAVAILABLE Currency conversion failed

Roadmap

v2.1 — Advanced Rules

  • Rule versioning (edit without losing history)
  • Conflict detection (overlapping rules)
  • Rule testing (dry-run against test cases)
  • Scheduled activation/deactivation

v2.2 — Analytics

  • Revenue by segment report
  • Discount leakage detection
  • Price change impact analysis
  • Margin reports by SKU/channel

v2.3 — Experiments

  • A/B pricing experiments
  • Statistical significance calculation
  • Automatic winner promotion

v3.0 — Persistence & Scale

  • PostgreSQL backend (event-sourced)
  • Redis caching for hot paths
  • Bulk calculation (50K items)
  • Wasm custom action functions

Documentation

Document Description
mcp-server.toml ADK-Rust Enterprise registry manifest
CHANGELOG.md Version history
Rust Docs Generated API documentation

Contributing

Contributions welcome. Priority areas:

  • Additional CEL context variables
  • Competitor price monitoring integration
  • Subscription/metered billing support
  • Multi-currency price lists
  • Approval workflow chains

Contributors

James Karanja Maina

License

Apache-2.0 — see LICENSE for details.

Part of the ADK-Rust Enterprise MCP server ecosystem.

Built with ❤️ by Zavora AI

Registry Compliance

This server implements the ADK MCP SDK contract:

  • HealthCheck — async health probe for registry monitoring
  • mcp-server.toml — manifest declaring tools, risk classes, and credentials
  • Structured tracing — RUST_LOG env-filter for observability
  • Audit trail — every mutation logged with actor, timestamp, and details