capacity-planner

Purpose

1. Capacity sizing at 70/80/90% utilization against P50/P90/P99 demand, with P(SLA breach) at each point and a SAFE/WATCH/AT_RISK/CRITICAL risk band.
2. Utilization health at the per-member traffic-light level plus a team verdict (HEALTHY/SQUEEZED/OVERLOADED/UNBALANCED).
3. 12-month quarterly hiring plan accounting for ramp curves, attrition, QoQ demand growth, and span-of-control manager triggers.

When to use

• Annual ops capacity planning (October-November for the following fiscal year).
• Quarterly re-sizing if demand changed >15% or attrition spiked.
• Pre-budget defense — the math that justifies the headcount ask to your CFO.
• Diagnostic when an ops team is missing SLA and you need to know whether it's a sizing problem, a process problem, or a bottleneck problem.
• M&A / new-segment launch modeling — sizing a new team or combined org.

Workflow

1. Intake demand. Pull P50/P90/P99 daily ticket/case volume from your work system (Zendesk, Intercom, JSM, ServiceNow, Salesforce). If you only have averages, stop and pull the distribution. Single- point demand estimates are the most expensive anti-pattern in ops.
2. Model throughput. Run

   capacity_modeler.py

   with your demand, AHT, SLA target, current FTE, and shrinkage. Use

   --profile

   for your function (support / cx / bizops / finance-ops / it-ops). Read the 80%-utilization row — that's your sizing point.
3. Flag utilization risk. Run

   utilization_analyzer.py

   against your current team's actual utilization data. Anyone >85% sustained is a throughput-collapse risk per Reinertsen. Spread >30 percentage points across team means UNBALANCED — fix that before hiring.
4. Sequence hiring. Run

   hiring_sequencer.py

   with current FTE, target EOY, ramp time, attrition, and growth. It will front-load hires (Q1 35%, Q4 15%), apply ramp curves, and trigger a manager hire when span of control crosses 7 ICs/manager.
5. Walk the Forcing-question library (see below). One question at a time. Do not skip ahead. Answers must be written down before you commit the plan.

Scripts

• scripts/capacity_modeler.py

  — Erlang-C sizing with shrinkage adjustment and P50/P90/P99 breach probabilities.

  --profile

  for industry defaults.

• scripts/utilization_analyzer.py

  — per-member traffic-light + team-level health verdict with variance detection.

• scripts/hiring_sequencer.py

  — 12-month quarterly plan with ramp, attrition, growth, max-hires-per-quarter constraint, and manager-trigger logic.

--input <path>

--output {markdown,json}

--sample

--help

References

• references/queueing_theory_canon.md

  — Erlang, Little, Hopp & Spearman, Reinertsen, Kingman, Cleveland, ITIL, Armony et al. (8 sources). The math.

• references/ops_workforce_planning_canon.md

  — Fournier, Larson, Google SRE Workbook, Frei, Lawler, Bersin, Gartner, Grove (8 sources). The people factors.

• references/capacity_anti_patterns.md

  — 11 named anti-patterns with cited sources, tool guards, and the meta-discipline that Lencioni + Goldratt + Christensen impose. (8+ named sources.)

Assets

• assets/capacity_brief_template.md

  — 20-minute fill-out template with JSON skeletons for all three tools and an output checklist.

Assumptions

• Work is queued (tickets, cases, work items) — not project-style. If your team's work isn't queued, this is the wrong skill.
• Demand has a stationary-enough distribution within a quarter. Step-changes (new product launch, M&A, regulatory shift) require re-running mid-quarter.
• You have at least 90 days of historical demand data to compute P50/P90/P99. If not, generate the distribution from your sales / user-base forecast first.
• Service is single-class within a queue. If you have hard priority tiers (P1/P2/P3 with class-specific SLAs), model each as a separate queue and sum.
• Channels are modeled coherently. Multi-channel teams use the appropriate

  --profile

  with built-in shrinkage premium.

Anti-patterns

references/capacity_anti_patterns.md

1. Plan-to-100%-utilization (Reinertsen Principle 12)
2. Treat-ramp-as-instant (Larson)
3. Ignore-attrition-in-12-month-plan (Bersin)
4. Hire-ICs-forever-with-no-manager-trigger (Fournier)
5. Size-to-P50-demand-only (Cleveland)
6. No-shrinkage-adjustment (Cleveland, SRE Workbook)
7. Single-channel-model-for-multi-channel-work (Gartner, Kingman)
8. No-surge-plan-for-P99-events (Hopp & Spearman, Reinertsen)

Distinct from

• c-level-advisor/vpe-advisor

  measures engineering throughput via DORA 4 metrics, story points, deployment frequency, and cycle time bottlenecks. It is for engineering teams shipping code. This skill is for ops teams handling tickets/cases. Different unit of work, different math (Erlang-C vs. DORA), different bottleneck (queueing-blind staffing vs. WIP + lead time).

• c-level-advisor/chro-advisor

  does strategic workforce planning (1-5 year capability portfolios, talent supply, leadership succession). This skill does operational 0-12 month capacity sizing against demand. Per Lawler: conflating them gets you hired into the wrong jobs.

• project-management/*

  tracks delivery throughput on projects (Jira velocity, sprint capacity). This skill sizes around steady- state queued work.
• Sibling

  process-mapper

  finds the bottleneck. This skill sizes the team around a known bottleneck. Order of operations: process-mapper first → capacity-planner second. Hiring around the wrong constraint wastes the hires.

• business-growth/cs-coverage

  (if it exists) sizes Customer Success coverage by ARR/CSM ratio and segment. This skill sizes by queued work volume (tickets, cases, escalations). For a CS team that handles both relationship work AND a ticket queue, run both.

Forcing-question library (Matt Pocock grill discipline)

Q1 — "What is your bottleneck, and have you confirmed it empirically?"

process-mapper

Q2 — "What service trade-off are you accepting?"

Q3 — "What's your demand P90, and what's the gap to your P99?"

Q4 — "At your planned utilization, what is P(SLA breach) at P90 and at P99?"

10% you are understaffed at the sizing point. If P(breach at P99) > 50% you have no surge plan and the next peak event will be visible to the CEO.

Q5 — "Have you budgeted replacement hires for the attrition you'll see this year?"

Q6 — "When does span of control trigger a manager hire, and who is the candidate?"

hiring_sequencer.py

Q7 — "What is your surge plan for the P99 day?"