azure-cost-calculator

What this skill does

# Azure Cost Calculator

Deterministic Azure cost estimation using the public Retail Prices API. Never guess prices; always query the live API via the scripts.

## Runtime Detection

Choose the script runtime based on what is available:

| Runtime                    | Condition                                                                                                                                                | Pricing script                 | Explore script                     |
| -------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------ | ---------------------------------- |
| **Bash** (preferred)       | `curl` and `jq` available                                                                                                                                | `scripts/get-azure-pricing.sh` | `scripts/explore-azure-pricing.sh` |
| **PowerShell 7+**          | `pwsh` available                                                                                                                                         | `scripts/Get-AzurePricing.ps1` | `scripts/Explore-AzurePricing.ps1` |
| **Windows PowerShell 5.1** | `powershell.exe` available (Windows only). Add `-ExecutionPolicy RemoteSigned` before `-File` to avoid silent failures from default policy restrictions. | `scripts/Get-AzurePricing.ps1` | `scripts/Explore-AzurePricing.ps1` |

Both produce identical JSON output. Bash flags use `--kebab-case` equivalents of PowerShell `-PascalCase` parameters (e.g., `-ServiceName` → `--service-name`).

### Declarative Parameters

Service reference files specify query parameters as `Key: Value` pairs. Translate to Bash `--kebab-case` or PowerShell `-PascalCase` flags; quote string values with spaces. See [workflow.md](references/workflow.md) for the full parameter table, translation examples, and output formats.

## Workflow

### Phase 1: Analysis (no API queries)

1. **Parse**: extract resource types, quantities, and sizing from user's architecture
2. **Clarify**: if any of these are true, stop and ask before continuing:
   - A resource maps to a category but not a specific service (e.g., "a database") → list 2–4 options
   - A resource has no count, no sizing/tier, or no workload scale → ask for specifics
   - A resource has no expected monthly volume: data transferred/ingested (GB), transactions, requests, messages, tokens, or users/devices → ask for estimated volume
   - A multi-model or multi-feature service (e.g., Azure OpenAI, AI Services, Defender for Cloud) has no model or feature variant specified → ask which one (cost can vary 15–30×)
   - User describes a goal without a hosting model (e.g., "a web app") → present 2–3 options with trade-offs
   - Batch all gaps into one prompt. Offer concrete choices with sensible options (e.g., "100 GB/month?", "GPT-4o or GPT-4o-mini?"). One round max; if user declines a specific parameter, apply safe defaults only for **Safe-default** gaps and disclose them; if any **Never-assume** gap remains, do NOT proceed; state what cannot be estimated without the missing input.
3. **Locate** each service reference using the lookup workflow in [shared.md](references/shared.md) (file search → routing map → category browse → broad search → discovery)
4. **Read** matched service files; check `billingNeeds` and follow dependency chains (e.g., AKS → VMs → Managed Disks)
5. **Classify** each parameter using the Disambiguation Protocol in [shared.md](references/shared.md):
   - **Specified**: user provided value (use verbatim)
   - **Never-assume gap**: required parameter missing (must ask)
   - **Safe-default gap**: optional parameter missing (use default, disclose)
6. **Specification Review**: present a summary:

   | Service | Specified | Missing (will ask) | Defaults (will assume) |
   | ------- | --------- | ------------------ | ---------------------- |
   - If **any never-assume parameter** is missing → ask user before proceeding
   - If only safe-default gaps remain → disclose defaults and proceed to Phase 2
   - **Single-service shortcut**: skip this table for single-service estimates where all parameters are specified

### Phase 2: Estimation

7. **Query**: run the pricing script for each service using parameters from service files + user input + resolved defaults
8. **Calculate**: apply cost formulas from service files; multiply by quantities
9. **Verify arithmetic**: for each line item, restate the formula with actual numbers, compute, and confirm the result. If any intermediate calculation involves multiplication of two numbers > 10, compute it step-by-step (e.g., `14.5 × 640 → 14 × 640 → 10 × 640 = 6,400; 4 × 640 = 2,560; subtotal = 8,960; 0.5 × 640 = 320; total = 9,280`). Do not rely on mental math for multi-digit operations.
10. **Present**: output the estimate with:

- **Assumptions block** (see Disambiguation Protocol in shared.md), listed before cost numbers
- **Line items**: service, unit price, quantity/hours, monthly cost
- **Grand total**: re-sum all line-item monthly costs independently; if discrepancy, use re-summed value

### Post-Estimate Iteration

After presenting the estimate, the user may request changes (switch region, add RI, resize instances, add/remove services). Re-run only the affected queries; do not restart the full workflow.

## Reference Index (load on demand)

| Condition                                                                       | Read                                                                                                                                                                                                                             |
| ------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Always (entry point)                                                            | [references/shared.md](references/shared.md): constants, category index, alias lookup                                                                                                                                           |
| Query returned 0 results or wrong data                                          | [references/pitfalls.md](references/pitfalls.md): troubleshooting and traps                                                                                                                                                     |
| User asks about Reserved Instances or savings plans                             | [references/reserved-instances.md](references/reserved-instances.md)                                                                                                                                                             |
| Non-USD currency or non-eastus region                                           | [references/regions-and-currencies.md](references/regions-and-currencies.md)                                                                                                                                                     |
| User requests private endpoints or private access; confirm PE intent with user | [references/services/networking/private-link.md](references/services/networking/private-link.md): PE pricing, [references/services/networking/private-dns.md](references/services/networking/private-dns.md): DNS zone pricing |
| File search returned 0 or ambiguous results                                     | [references/service-routing.md](references/service-routing.md) - implemented services routing                                                                                                                                    |
| First time running scripts or unfam