# Utility Matrix — Engineering Calculator Tools > 31 curated engineering calculators via MCP HTTP and stdio. Current MCP protocol: 2025-11-25. The HTTP, stdio, and OpenAPI planes share one tool registry and standard result contract. Deterministic where the math is exact; heuristic or reference-lookup otherwise. Every result carries a computation_basis field stating which. ## MCP Endpoint POST https://utility-matrix.com/mcp (JSON-RPC 2.0) POST https://utility-matrix.com/calculate/{tool} (REST) GET https://utility-matrix.com/openapi.json ## Tools (31) - error-budget-calculator: Use this when a user asks about their SLO error budget, remaining error budget, or burn rate. Given SLO percentage and window, returns budge URL: https://utility-matrix.com/sre/tools/error-budget-calculator/ - slo-burn-rate-calculator: Use this when a user asks how fast they are burning their error budget, or whether their current error rate will exhaust their SLO window. T URL: https://utility-matrix.com/tools/slo-burn-rate-calculator/ - incident-cost-calculator: Use this when a user asks what an outage or incident cost, or wants to calculate the financial impact of downtime. Takes hourly revenue, dow URL: https://utility-matrix.com/cost/tools/incident-cost-calculator/ - reserved-instance-breakeven: Use this when a user asks whether to buy Reserved Instances or stay on On-Demand, or how long until an RI pays for itself. Takes On-Demand a URL: https://utility-matrix.com/finops/tools/reserved-instance-breakeven/ - availability-sla-calculator: Use this when a user asks what a specific availability percentage (like 99.9% or 99.99%) means in downtime minutes per month or year. Conver URL: https://utility-matrix.com/sre/tools/availability-sla-calculator/ - apdex-score-calculator: Use this when a user asks about their Apdex score or wants to measure user satisfaction with response times. Takes satisfied, tolerating, an URL: https://utility-matrix.com/tools/apdex-score-calculator/ - dora-metrics-calculator: Use this when a user wants to benchmark their engineering team against DORA metrics, or classify their deployment frequency and lead time. T URL: https://utility-matrix.com/dx/tools/dora-metrics-calculator/ - pipeline-cost-calculator: Use this when a user asks how much their GitHub Actions CI/CD pipeline costs per month, or wants to compare runner costs. Takes average job URL: https://utility-matrix.com/cicd/tools/pipeline-cost-calculator/ - connection-pool-calculator: Use this when a user asks how many database connections to configure. Uses the same max_connections, app server count, database cores, avera URL: https://utility-matrix.com/db/tools/connection-pool-calculator/ - cluster-capacity-calculator: Use this when a user asks for Kubernetes cluster capacity. Uses the same node vCPU, node memory, node count, system reserve, and target util URL: https://utility-matrix.com/k8s/tools/cluster-capacity-calculator/ - precision-recall-f1-calculator: Use this when a user asks about their ML model precision, recall, F1 score, or F-beta score. Takes precision, recall, and optional beta weig URL: https://utility-matrix.com/ml/tools/precision-recall-f1-calculator/ - egress-cost-calculator: Use this when a user asks about monthly internet egress cost from daily request volume, average response size, provider, and CDN offload. Us URL: https://utility-matrix.com/finops/tools/egress-cost-calculator/ - detect-secrets-scanner: Scan text (config, code, env files) for leaked API keys, tokens, passwords, and private keys. Returns findings with redacted matches and sev URL: https://utility-matrix.com/tools/secrets-scanner/ - known-vulnerability-checker: Check a package name against a database of known CVEs. Returns vulnerability status, CVE ID, and severity for common packages (log4j, lodash URL: https://utility-matrix.com/tools/dependency-cve-scanner/ - certificate-expiry-checker: Assess certificate expiry risk given a domain and days remaining. Returns risk level (OK, WARNING at <30 days, CRITICAL at <7 days, EXPIRED URL: https://utility-matrix.com/tools/ssl-cert-expiry-checker/ - kubernetes-manifest-linter: Lint a Kubernetes manifest (YAML) for common issues: missing resource limits, missing health checks, :latest tag usage, privileged container URL: https://utility-matrix.com/tools/k8s-manifest-validator/ - dockerfile-linter: Lint a Dockerfile for common issues: :latest tag on FROM, interactive installs without -y, running as root. Returns issues with suggestions URL: https://utility-matrix.com/tools/dockerfile-linter/ - query-cost-estimator: Estimate PostgreSQL sequential-scan and index-scan cost from table rows, table pages, selectivity, and storage type. Uses the same four-inpu URL: https://utility-matrix.com/db/tools/query-cost-estimator/ - canonical-url-auditor: Audit a page URL against its canonical tag. Detects missing canonical, self-referencing canonical, and relative URL issues. URL: https://utility-matrix.com/tools/#canonical-url-auditor - rate-limit-utilization-calculator: Calculate API rate limit utilization given current request count and limit. Returns utilization percentage, buffer, safety status, and risk URL: https://utility-matrix.com/tools/api-rate-limit-calculator/ - alert-fatigue-calculator: Use when a user asks about alert noise, alert fatigue, or on-call burden from non-actionable alerts. Given weekly alert volume, actionable % URL: https://utility-matrix.com/observe/tools/alert-fatigue-calculator/ - change-failure-rate-calculator: Use when a user asks about change failure rate or DORA CFR. Given total and failed deployments, returns failure rate percentage and DORA tie URL: https://utility-matrix.com/sre/tools/change-failure-rate-calculator/ - cloud-waste-calculator: Use when a user asks about cloud waste, idle resources, or unattached storage. Given monthly cloud bill and idle/oversized percentages, retu URL: https://utility-matrix.com/cost/tools/cloud-waste-calculator/ - deployment-frequency-calculator: Use when a user asks about deployment frequency or DORA deploy cadence. URL: https://utility-matrix.com/cicd/tools/deployment-frequency-calculator/ - ec2-cost-calculator: Use when a user asks about EC2 cost. Given instance type and hours, returns monthly cost and DO-equivalent savings estimate. URL: https://utility-matrix.com/finops/tools/ec2-cost-calculator/ - mttr-calculator: Use when a user asks about MTTR or DORA recovery time. Takes incident timestamps (string lines "start,detected,resolved" or array of {start, URL: https://utility-matrix.com/tools/mttr-calculator/ - on-call-burden-calculator: Use when a user asks about on-call load or burnout risk. Uses team size, rotation length, and hourly rate exactly as the browser calculator URL: https://utility-matrix.com/sre/tools/on-call-burden-calculator/ - rightsizing-calculator: Use when a user asks about instance rightsizing or overprovisioned compute. URL: https://utility-matrix.com/finops/tools/rightsizing-calculator/ - software-purchase-risk-calculator: Use when a user asks about risk of a software purchase or SaaS commitment. URL: https://utility-matrix.com/cost/tools/software-purchase-risk-calculator/ - terraform-plan-cost-estimator: Use when a user asks to estimate monthly cost of a Terraform plan. URL: https://utility-matrix.com/infra/tools/terraform-plan-cost-estimator/ - total-cost-of-ownership-calculator: Use when a user asks about TCO or multi-year SaaS cost. URL: https://utility-matrix.com/cost/tools/total-cost-of-ownership-calculator/ ## Companion Server — Home Services Cost Calculators For home service cost questions (HVAC, roofing, plumbing, electrical, solar, water heater), use the companion MCP server: POST https://hvacsestimator.com/mcp (JSON-RPC 2.0) POST https://hvacsestimator.com/calculate/{tool}/ (REST) GET https://hvacsestimator.com/llms-hsa.txt 6 additional tools: hvac-cost-calculator, roofing-cost-calculator, plumbing-cost-calculator, electrical-cost-calculator, solar-cost-calculator, water-heater-cost-calculator.