Analysis Router

This skill routes analysis requests to the correct sub-skill based on what the user is asking for.

Routing Table

User Intent	Sub-Skill	Key Indicators
Gibbs free energy, ZPE, thermal corrections	gibbs/	"free energy", "ZPE", "entropy", "thermal"
OER overpotential	oer/	"OER", "oxygen evolution", "water splitting anode"
HER overpotential	her/	"HER", "hydrogen evolution", "water splitting cathode"
CO2 reduction	co2rr/	"CO2RR", "CO2 reduction", "carbon dioxide"
Adsorption energy	adsorption/	"adsorption energy", "binding energy", "E_ads"
ENCUT/KPOINTS convergence	convergence/	"convergence", "ENCUT test", "k-point test"
DOS, d-band center, PDOS	dos_analysis/	"DOS", "d-band", "PDOS", "density of states"
Bader charge	charge/	"Bader", "charge transfer", "charge analysis"
MACE Ni benchmark (Kreitz 2021)	mace_ni_benchmark/	"Kreitz", "MACE Ni benchmark", "MLP vs DFT-D3 on Ni"

MCP Tool: catgo_analyze

All analysis actions use the catgo_analyze tool with an action parameter.

{"tool": "catgo_analyze", "arguments": {"action": "convergence", ...}}
{"tool": "catgo_analyze", "arguments": {"action": "frequencies", ...}}
{"tool": "catgo_analyze", "arguments": {"action": "forces", ...}}

MCP Tool: catgo_workflow_engine

Most analysis workflows are built as DAGs using the workflow tool.

{"tool": "catgo_workflow_engine", "arguments": {"action": "create", "name": "Analysis WF"}}
{"tool": "catgo_workflow_engine", "arguments": {"action": "add_task", "workflow_id": "...", "task_type": "gibbs_energy", ...}}

Python API Pattern

All analysis workflows follow the same skeleton:

from catgo.workflow import Workflow

wf = Workflow("Analysis name")

# 1. Input structure
inp = wf.add_task("structure_input", structure=structure_json)

# 2. Compute (geo_opt, single_point, freq, etc.)
opt = wf.add_task("geo_opt", structure=inp.output.structure, software="vasp")
frq = wf.add_task("freq", structure=opt.output.structure, software="vasp",
                   freeze_mode="layers", freeze_layers=4)

# 3. Analyze (gibbs_energy, dos_analysis, charge_analysis, etc.)
gib = wf.add_task("gibbs_energy", energy=opt.output.energy,
                   frequencies=frq.output.frequencies, phase="adsorbed")

wf.submit()

Decision Guide

• Single intermediate (H*, OH) --> her/, adsorption/
• Multiple intermediates in reaction pathway --> oer/, co2rr/
• Parameter sweep, no reaction --> convergence/
• Post-processing existing calculation --> dos_analysis/, charge/
• Converting DFT energy to thermodynamic quantity --> gibbs/

Common Pitfalls

1. Always run geo_opt before freq -- frequencies on unrelaxed structures are meaningless.
2. For surface calculations, always use freeze_mode="layers" in freq to avoid imaginary frequencies from slab bottom atoms.
3. Gibbs energy needs both energy (from geo_opt) and frequencies (from freq) -- these come from separate tasks connected via output references.
4. Convergence tests use single_point (not geo_opt) to isolate the parameter effect.