mlff-screening-and-relaxation

name	mlff-screening-and-relaxation
description	Use this skill for MLFF single-point screening, ranking, and geometry relaxation when choosing among enabled MACE, FairChem UMA, MatterSim, or ORB-v3 backends.
license	project-local
allowed-tools	ls read_file write_file edit_file execute get_avail_remote_task get_remote_task_spec remote_submission remote_submission_batch

mlff-screening-and-relaxation

Overview

Prepare deterministic SP/relax stages, choose an enabled backend, and keep backend settings separate from operation settings.

Quick Start

1. Read remote-stage-layouts, then put uniquely named structures directly under a clean input/.
2. Call get_avail_remote_task, then query the intended backend directly with detail="full", for example get_remote_task_spec(task_name="mlff_sp", template_overrides={"backend": "mattersim"}, detail="full"); do not query {} first when selecting a non-default backend.
3. Pass only nested backend, backend_config, and task_config overrides returned by that query.
4. Submit one stage with remote_submission; submit two or more independent same-config stages with one remote_submission_batch. Leave submission_config.resources and .machine unset.
5. Inspect output/batch_summary.json and per-input summaries. Use receipt recovery only after a returned failure.

Allowed tools

• ls
• read_file
• write_file
• edit_file
• execute
• get_avail_remote_task
• get_remote_task_spec
• remote_submission
• remote_submission_batch

Workflow

1. Select operation before backend

• Use mlff_sp for energies/forces on unchanged geometries and mlff_relax when positions or the cell must be optimized.
• Query the concrete backend schema before overrides. Do not reuse MACE keys after switching to UMA, MatterSim, or ORB-v3.
• Empty overrides use the administrator-enabled default backend. If no default is effective, choose one of the returned available_backends explicitly.

2. Build one deterministic stage

• Put files directly under input/; do not submit recursive project trees.
• Preserve atom constraints and source provenance. Reject filename-stem collisions such as case.xyz plus case.vasp in one stage.
• For UMA, set shared physical metadata in backend_config.defaults and exceptions in backend_config.items, keyed by exact filenames relative to input/.

3. Group for model reuse

• One stage initializes one selected model and processes its structures sequentially.
• For similarly sized short relaxations, 30-50 structures per stage is an empirical starting point, not a probe requirement or hard limit. Use smaller groups for heterogeneous costs.
• SP can use substantially larger groups. Split only into complete, independently runnable stages.

4. Interpret as MLFF evidence

• Verify backend, model/checkpoint, provider version, precision/device, method settings, per-input errors, and actual outputs.
• Use a consistent backend/model/domain task across structures being ranked unless a difference is scientifically intentional and reported.
• Treat MLFF screening as triage unless the user explicitly accepts ML-potential accuracy for the conclusion.

Method-critical defaults

• MACE is the initial deployment default: model=mh-1, head=omat_pbe, dispersion=false, and float64 for SP/relax. State any change that affects comparability.
• Choose dispersion explicitly for adsorption-energy comparisons and apply the same choice to clean slab, adsorbate, and references.
• Keep relax_cell=false unless periodic-cell optimization is intended; cell relaxation requires a valid fully periodic cell.
• For UMA omol, set charge and multiplicity-style spin explicitly. Non-omol UMA tasks require charge and spin zero.
• MatterSim-v1 is a bulk-material model; do not present surface, interface, or long-range-interaction results as quantitative without validation.
• ORB-v3 defaults to precision=float32-high; change precision only as a declared numerical choice.

Output Contract

Return:

• operation, backend, model/checkpoint, and method-critical overrides;
• stage path or batch root with first-level stage count;
• work_dir_rel, remote_context_id, submission_hash, and receipt_rel when present;
• output/batch_summary.json, per-input error count, and shortlist/keep-drop rule;
• the boundary between MLFF screening and any downstream reference calculation.

References

• MACE fields and model semantics: references/mace.md
• FairChem UMA domain and charge/spin semantics: references/fairchem_uma.md
• MatterSim scope and model identity: references/mattersim.md
• ORB-v3 precision and confidence metadata: references/orb_v3.md