π pi-molagent
Get started →
pi coding agent · molecular simulation package

Stop reinventing
molecular simulation workflows.

pi-molagent bundles 12 skills covering the full OPLS-AA parameterization, polymer building, LAMMPS data prep, DFT charge / dihedral refinement, and plotting pipeline — plus steering content and HPC guards that keep the pi coding agent disciplined on login nodes.

12 skills
Pre-built pipelines
3 engines
OPLS · LAMMPS · g16
RULE #0
Login-node guard
0 outbound
Your data stays yours
PROBLEM

Generic AI coding agents don't know LAMMPS.

Out of the box they invent force-field parameters, propose unconverged k-points, and forget your group's conventions. A plausible wrong answer burns weeks of compute.

01
No memory of conventions
Every chat starts from zero. Input parameters, force-field choices, training recipes — all scattered across individuals.
Recurring
02
Hallucinated force fields
General LLMs guess OPLS atom types and bond parameters. Wrong by construction — and the simulation will run anyway.
Dangerous
03
Login-node compute disasters
Agents fork Python loops on login nodes. HPC admins notice. Your account gets a strongly-worded email.
Critical
04
Working scripts get "improved"
A validated input deck gets a "cleanup" pass and silently changes the physics. Now you debug for a week.
Systemic
01 · SKILLS

12 skills, end-to-end molecular pipelines.

Each skill is a self-contained SKILL.md plus helper scripts. The pi agent loads them on demand when the task matches.

STRUCTURE

structure-analyze

Mol2 / PDB structure analysis, ring detection, atom typing.

BUILDER

polymer-builder

Build oligomers and polymer chains from monomer mol2.

FORCE FIELD

ligpargen-from-mol

OPLS-AA parameterization via LigParGen + BOSS.

★ PIPELINE

opls-pipeline

End-to-end OPLS-AA pipeline: param → data → validate.

PACKING

solvent-pack

Pack solvent boxes with Packmol + LAMMPS equilibration.

DATA

merge-data

Merge multiple LAMMPS data files into one consistent box.

TRAJECTORY

wrap-unwrap

Wrap / unwrap LAMMPS trajectories across PBC.

DATA

extract-molecules

Extract and renumber molecules from bulk LAMMPS data.

QUANTUM

dft-charges

DFT charge derivation (Gaussian g16, Hirshfeld / RESP).

★ PIPELINE

dihedral-fit-pipeline

OPLS-AA dihedral fitting: DFT scan → LAMMPS coefficients.

ANALYSIS

plot-standards

Publication-quality matplotlib figure standards.

META

find-skills

List and describe available molagent skills.

02 · PIPELINES

Real workflows, end-to-end.

The skills compose into validated, group-tested pipelines. Each diagram below is exactly the sequence the agent runs — SLURM submits, gates, human checkpoints and all. Click a tab to inspect.

// every “compute” step runs through SLURM; only stdlib-Python helpers ever execute on the login node (RULE #0).

03 · WHY

Disciplined by construction.

Skills are only half the story. pi-molagent ships steering content that encodes how a careful computational chemist actually works.

01

RULE #0 hook

A tool_call hook blocks Python-on-login-node before SLURM admins do. Configurable: warn / strict / off.

02

No reinstalls

RULE #1 forbids the agent from running pip install or conda install without your explicit "yes". The cluster has it already.

03

No silent refactors

RULE #2: validated user scripts are off-limits to "improvements". The agent adds drivers on top instead of rewriting internals.

04

Critic + Verifier

Subagents for devil's-advocate review and blind re-derivation of numerical claims. Invoke with /critic and /verify.

05

Knowledge on demand

/hpc, /lammps, /gaussian load curated references for partitions, OPLS defaults, g16 conventions.

06

Single config file

All paths, binaries, SLURM settings, and policy live in one molagent.json. /molagent:doctor validates it.

07

SLURM-native

Compute skills emit SLURM job scripts and watch squeue/sacct. Auto-restart on failure where it makes sense.

08

Lessons library

Past-incident notes (LAMMPS gotchas, Colvars/PLUMED traps, plot discipline) so the agent stops repeating mistakes.

04 · INSTALL

One command. Four minutes.

pi-molagent is a pi coding agent package. Pi discovers skills, prompts, and extensions automatically. The only manual step is the steering symlink.

STEP 1 · Prerequisites

Install pi itself

$ npm install -g @earendil-works/pi-coding-agent
STEP 2 · Install pi-molagent

From git, global or project-local

# Global install
$ pi install git:git@github.com:your-org/pi-molagent

# Project-local (recommended for shared HPC projects)
$ pi install -l git:git@github.com:your-org/pi-molagent
STEP 3 · Auto-load steering

Symlink AGENTS.md so pi finds it

$ pi list                                  # find install path
$ ln -s /abs/path/pi-molagent/steering/AGENTS.md \
      ~/.pi/agent/AGENTS.md
STEP 4 · Configure & verify

Generate config, run doctor

 /molagent:init     # inside pi
 /molagent:doctor   # env + skill readiness report
05 · RULES

Three rules the agent won't break.

These are not suggestions in a prompt. RULE #0 is enforced by a pi extension hook; RULE #1 and #2 are baked into steering/AGENTS.md and loaded before every session.

RULE #0

Login node is off-limits for compute.

No Python with numpy / scipy / torch / RDKit on the login node. No conda activate followed by anything that spawns Python. No xargs -P. When in doubt, SLURM. Enforced by a tool_call hook with warn / strict / off policy.

Enforced · extension hook
RULE #1

Never install software without an explicit "yes".

No pip install, no conda install, no source builds, no ~/.bashrc edits. The cluster has every major scientific package preinstalled — find the module, ask if it fails.

Steering · AGENTS.md
RULE #2

Don't refactor working scripts.

Validated user scripts are off-limits to "improvements". When automation is requested, the agent adds a driver on top — it does not rewrite internals.

Steering · AGENTS.md
ready to ship

A computational-chemistry co-pilot, one install away.

Your scientists shouldn't be spending their days writing input files. Hand the boilerplate to pi-molagent and keep them on the science.