simspec-author

A tool that combines outputs from paper, physics, and claim analysis into one checked JSON specification for a simulation. It records unclear points instead of guessing.

In plain words
What is it for?
It is used to prepare a validated simulation specification before generating Python code, visual elements, sliders, or narration.
Why use it?
It gives later simulation steps one agreed source of truth and prevents errors from spreading when the specification is incomplete or inconsistent.

Skill for Claude CodeCodex

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.

agentmods
npx agentmods add skills/leventilo/mobius/simspec-author
Any agent
npx skills add leventilo/mobius --skill simspec-author
Clone the repo
git clone --depth 1 https://github.com/leventilo/mobius

Made for: Claude Code, Codex.

Per session 59 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 5,582 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00059 $0.05582
Opus 5 $0.00030 $0.02791
Sonnet 5 $0.00012 $0.01116
Haiku 4.5 $0.00006 $0.00558

Measured 2d ago against content hash ca1f2b20d53a, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

simspec-author 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 2d 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/simspec-author/SKILL.md · 346 lines

How it starts

The opening of the file, as written. The whole thing — 346 lines — stays where its author put it; the contents beside it link to each section on GitHub.

simspec-author

Purpose and scope

This skill composes a single typed JSON document, the SimSpec, from artifacts produced by three upstream skills. It is the load-bearing handoff point of the Mobius DAG: every downstream agent reads the SimSpec and writes back into it. If the SimSpec is wrong, every primitive, every slider, every narration segment downstream is wrong.

What this skill does NOT do. It does not infer physics from a paper - that is physics-interpreter. It does not generate Python code for primitives - that is primitive-generator. It does not check unit homogeneity, CFL bounds, conservation residuals, or figure-diff - those are the five scripts of science-integrity. It does not invent numerical values that are not present in upstream artifacts. It is a typed-merge skill with explicit ambiguity logging, nothing more. Its place in the DAG is between the three input streams (paper-parser, physics-interpreter, claim-extractor) and the rest of the pipeline (primitive-generator, science-integrity, viz-mapper, paper-diff, narration).

Inputs

The skill expects three upstream artifacts on disk in the current working directory.

paper.json from paper-parser populates the paper.* subtree directly: arxivId, doi, title, authors, abstractHash, figures[]. Each figure carries a caption and a list of extracted_claims produced by Opus 4.7 vision over the figure bitmap.

physics.json from physics-interpreter populates the entire physics.* subtree: governing_equations[] with paired LaTeX and sympy strings, boundary_conditions[], initial_conditions[], constants[] annotated by source (paper, standard, derived), the regime enum, and the named approximations[] array.

claims.json from claim-extractor populates paper.numerical_claims[] and supplements figures[i].extracted_claims. Each claim ships a value, a UCUM unit, the section anchor, the extractor's self-rated confidence, and a verbatim source_quote for traceability.

Read the full file on GitHub · 346 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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. 2d ago First seen · 346 lines · 59 tokens per session scan A ca1f2b20d53a

Subscribe to this mod's changes

simspec-author is a skill published in the GitHub repository leventilo/mobius (9 stars, last pushed 4mo ago), licensed MIT. It adds 59 tokens to every session and 5,582 once invoked, about $0.0003 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 2026-08-31.

Related

Other skills, from other repositories

instrument-data-to-allotrope

Convert laboratory instrument output files (PDF, CSV, Excel, TXT) to Allotrope Simple Model (ASM) JSON format or flattened 2D CSV. Use this skill when scientists need to standardize instrument data for LIMS systems, data lakes, or downstream analysis. Supports auto-detection of instrument types. Outputs include full…

anthropics/knowledge-work-plugins · 123 tokens

biopython

Comprehensive molecular biology toolkit. Use for sequence manipulation, file parsing (FASTA/GenBank/PDB), phylogenetics, and programmatic NCBI/PubMed access (Bio.Entrez). Best for batch processing, custom bioinformatics pipelines, BLAST automation. For quick lookups use gget; for multi-service integration use…

K-Dense-AI/scientific-agent-skills · 76 tokens

exploratory-data-analysis

Perform bounded, local exploratory analysis of explicitly supported scientific files. Use for redacted CSV/TSV/JSON profiles; optional NumPy, HDF5, FASTA/FASTQ, and basic image metadata inspection; missingness/leakage audits; outlier and transformation sensitivity; and rigorous EDA report scaffolds. Other domain…

K-Dense-AI/scientific-agent-skills · 83 tokens

arboreto

Infer gene regulatory networks (GRNs) from gene expression data using scalable algorithms (GRNBoost2, GENIE3). Use when analyzing transcriptomics data (bulk RNA-seq, single-cell RNA-seq) to identify transcription factor-target gene relationships and regulatory interactions. Supports distributed computation for…

K-Dense-AI/scientific-agent-skills · 66 tokens

nature-statistics

Audit, revise, or draft manuscript statistical reporting for Nature / high-impact journal submissions. Use when the user asks to check statistical analysis sections, p values, confidence intervals, sample size, biological versus technical replicates, randomization, blinding, multiple-comparison correction, model…

Yuan1z0825/nature-skills · 139 tokens

paper-illustration

Generate publication-quality AI illustrations for academic papers using Gemini image generation. Creates architecture diagrams, method illustrations with Claude-supervised iterative refinement loop. Use when user says "生成图表", "画架构图", "AI绘图", "paper illustration", "generate diagram", or needs visual figures for papers.

wanshuiyin/Auto-claude-code-research-in-sleep · 67 tokens