Supplier concentration risk analysis

# Supplier concentration risk analysis

## Goal
Identify the suppliers that account for the bulk of spend (Pareto principle), detect single-source dependencies per category, and quantify concentration risk for the CFO and Procurement.

## Instructions

### Step 1 — Total spend per supplier over 12 months
```
Call spendesk_analyze_spend with:
  - groupBy: supplier
  - period: last 12 months
  - Retrieve: supplierId, supplierName, totalAmount, currency
Sort by totalAmount descending.
```

### Step 2 — Pareto analysis (80/20)
```
Calculate total spend (sum across all suppliers).
Calculate the cumulative % by walking through the suppliers sorted from largest to smallest.
Identify:
  - The number of suppliers accounting for 80% of spend (top concentration)
  - The % of suppliers accounting for 80% of spend
  - Suppliers each accounting for > 10% of total spend (critical risk)
```

### Step 3 — Identify single-source dependencies per category

⚠️ **Verified bug**: `category` does not exist as a `spendesk_analyze_spend` dimension (server error `"grouper is not a function"`). Employee-facing expense categories are carried by the "Analytic codes" analytical field — use the `analyticalCode` dimension instead:

```
Call spendesk_analyze_spend with groupBy: analyticalCode to get the categories.
For each category > 5% of total spend:
  Call spendesk_analyze_spend groupBy: [analyticalCode, supplier], filters.analyticalCodes=[<category id>]
  Identify if a single supplier = > 90% of the category (single-source), via the row's breakdown[]
```

### Step 4 — Enrich critical suppliers

⚠️ **Response-size risk**: `get_suppliers` embeds an `accountPayable.supplierIds` field that, for suppliers sharing a consolidated AP account, can hold hundreds of redundant IDs per record — even `pageSize=3` can already exceed the response size limit. Never paginate broadly here.

```
For suppliers accounting for > 5% of spend (usually a handful):
  Call get_suppliers with ids=[<id1>, <id2>, ...] (targeted, no broad pagination) to retrieve: country, status, IBAN country
Identify critical suppliers in geopolitically risky countries or
without a validated IBAN.
```

### Step 5 — Risk report
```
Present:
1. Overall concentration score: N suppliers = 80% of spend
2. Critical suppliers (> 10% of spend each) with amount + %
3. Single-source categories (1 dominant supplier)
4. Recommendations: suppliers to diversify as a priority
```

## Points of attention
- The 80/20 Pareto applies to spend tracked in Spendesk — spend outside Spendesk is not included
- A "critical" supplier doesn't always mean risk if it's a validated strategic partner
- Compare with the prior-year period to see if concentration is increasing

## Example prompts
- "Which are our most critical suppliers in terms of dependency?"
- "How many suppliers account for 80% of our purchases?"
- "Are there any categories where we only have one supplier?"
- "Show me our supplier concentration risk for the board"