timetabling-and-rostering

timetabling-and-rostering is a skill for Claude Code from hajibabaie/combinatorial-optimization-skills. It costs 133 tokens per session (13,436 once invoked), scanned A, original, MIT.

A guide to building timetables and staff rosters with rules that must never be broken and preferences that should be satisfied when possible. It covers methods for finding schedules under many constraints.

In plain words
What is it for?
Use it for course and exam timetables, nurse rosters, shift schedules, constraint models, and schedule validation.
Why use it?
It helps turn messy scheduling requirements into a model and shows when exact solving is too large, so a heuristic method is needed.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the combinatorial-optimization plugin — 76 skills shipped together

Good fit Use it for course and exam timetables, nurse rosters, shift schedules, constraint models, and schedule validation.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/hajibabaie/combinatorial-optimization-skills/timetabling-and-rostering
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add hajibabaie/combinatorial-optimization-skills --skill timetabling-and-rostering
Clone the repo
git clone --depth 1 https://github.com/hajibabaie/combinatorial-optimization-skills

Made for: Claude Code.

Or install combinatorial-optimization, the plugin that ships this one along with the rest of its 76 skills.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for timetabling-and-rostering

README.md
[![agentmods](https://agentmods.dev/badge/skills/hajibabaie/combinatorial-optimization-skills/timetabling-and-rostering/github.svg)](https://agentmods.dev/skills/hajibabaie/combinatorial-optimization-skills/timetabling-and-rostering)
Your own site
<a href="https://agentmods.dev/skills/hajibabaie/combinatorial-optimization-skills/timetabling-and-rostering"><img src="https://agentmods.dev/badge/skills/hajibabaie/combinatorial-optimization-skills/timetabling-and-rostering/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for timetabling-and-rostering

Your own site · 80×15
<a href="https://agentmods.dev/skills/hajibabaie/combinatorial-optimization-skills/timetabling-and-rostering"><img src="https://agentmods.dev/badge/skills/hajibabaie/combinatorial-optimization-skills/timetabling-and-rostering.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 133 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 13,436 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00133 $0.13436
Opus 5 $0.00067 $0.06718
Sonnet 5 $0.00027 $0.02687
Haiku 4.5 $0.00013 $0.01344

Measured 7d ago against content hash fabb0c19d242, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

timetabling-and-rostering scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 7d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/timetabling-and-rostering/SKILL.md · 819 lines

How it starts

The opening of the file, as written. The whole thing — 819 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Timetabling and Rostering

You are an expert in educational timetabling and personnel rostering. This skill covers hard/soft constraint modeling, MIP and CP-SAT formulations with modular constraint builders, the graph-coloring structure underneath period assignment, metaheuristic and matheuristic solution methods, and the ITC/INRC benchmark ecosystems. Use the framework below to classify the problem, build a constraint-modular exact model, validate solutions independently, and attach a heuristic when instances outgrow exact methods.

Initial Assessment

Establish the following before writing any model:

  • Problem family. Curriculum-based course timetabling (CB-CTT), post-enrolment timetabling (PE-CTT), exam timetabling, high-school timetabling, nurse rostering, or generic shift scheduling. The family fixes the natural decision variable and the benchmark literature to compare against.
  • Instance size. Courses/events, periods, rooms for timetabling; nurses, days, shift types for rostering. Estimate the variable count: a three-index model has roughly |events| x |periods| x |rooms| binaries. Above ~10^6 binaries, plan for decomposition or heuristics from the start.
  • Hard vs soft constraints. Get an explicit list. For each rule ask: "is a schedule that violates this rule unusable, or just worse?" The split is a stakeholder decision, not a mathematical one, and it changes the model structure (constraint vs penalized auxiliary variable).
  • Penalty weights or priority order. Benchmarks fix weights (ITC-2007, INRC); real clients usually give a priority ranking instead. Decide weighted-sum vs lexicographic early.
  • Feasibility status. Is a feasible solution known to exist (e.g., last year's timetable)? If not, plan an elastic model with violation slacks so you can report which hard rules clash instead of a bare "infeasible".
  • Solver availability. Gurobi license (full or size-restricted), or open-source only? OR-Tools CP-SAT is free and is the strongest free option for this problem class.
  • Data format. ITC-2007 .ctt files, INRC XML/JSON, XHSTT XML, or ad-hoc spreadsheets. Budget parsing and validation time for ad-hoc data; it is usually inconsistent.
  • Time budget. Interactive re-rostering needs seconds; a semester timetable can take hours. This drives the exact-vs-heuristic choice more than instance size does.
  • Horizon boundaries (rostering). Does history matter (consecutive-day counters, worked last weekend)? Rolling-horizon rosters need boundary state as input data.
  • Fairness requirements. Total penalty vs per-person balance. A roster optimal in total penalty can dump all night shifts on one nurse.
  • Re-optimization stability. If a published roster changes, how many changes are acceptable? Stability terms must be in the objective from the start.
  • Quality target. Proven optimum, benchmark-competitive soft penalty, or "feasible and visibly sensible"? Each target needs a different amount of machinery.

Read the full file on GitHub · 819 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 7d ago First seen · 819 lines · 133 tokens per session scan A fabb0c19d242

Subscribe to this mod's changes

timetabling-and-rostering is a skill published in the GitHub repository hajibabaie/combinatorial-optimization-skills (7 stars, last pushed 2mo ago), licensed MIT. It adds 133 tokens to every session and 13,436 once invoked, about $0.0007 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.

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