Add a problem type or objective

There is no plugin registry: problem types and objectives are enumerations of the contract, and the dispatch is by directory layout and model class. Adding one is a versioned contract change across the stack. Read the Formats page first.

In mamut-routing-lib

Concern	Where
the name	ProblemType / ObjectiveFunction in enums.py
the instance model	models.py (static) or td/models.py (time-dependent), pydantic with extra="forbid", format tags and versions for any new sidecar
layout parsing	artifacts.parse_layout and parse_collection_layout derive the problem type from the first path segment
loading	artifacts.load_benchmark_instance picks the model; instance_problem_type maps back by isinstance
validation	checker.check_solution / td/checker.check_td_solution and is_better_solution for the objective order
BKS files	<base>.bks.<Objective>.json; the store functions in bks.py / td/bks.py
CLI filters	the shared --problem-type / --objective options in cli.py
export	cvrplib.py if the classic format can express it
tests	one fixture instance per problem type in tests/, checker tests for every failure status

Bump the lib version; it is a contract change.

In MAMUT-routing-tools

Generation twins (generate derive-*), the TD traffic bridge, the solver wrapper (solve only knows PyVRP for static and KAYROS for TD Duration), the workbench's instance readers.

In the publisher and the website

site_payloads.py builds one payload kind per page (problem_index, family_index, ..., instance_page, objectives_page); a new problem type needs its index route, the objectives page text and the instance page descriptors. site.js renders payloads client-side, so any new field needs a renderer. The release builder needs nothing: it archives by (type, family).

In the documentation

The Benchmarks table, the Formats page, and the family sections. The family pages regenerate.

Write the report

State the pricing rule, the tie-breaks and the reference implementation in the module docstring of the checker and in the Formats pages, so later checkers can be validated against it.