Sas94

sas94-skill

A Claude Code skill for writing, reviewing, and debugging SAS 9.4 code with AI assistance.

SAS 9.4 is the daily driver for biostatisticians, health-services researchers, and pharma/claims analysts, yet SAS is underrepresented in LLM training corpora. This skill distills rules and idioms from MIT-licensed sources (sasjs/lint, sasjs/core) plus hand-transcribed SAS-programmer pitfalls (GWU data-mining curriculum), and routes Claude Code to topic-specific reference files on demand.

Status: v0.0.1 pre-release. Reference content is organized as per-topic atom directories under references/, with each atom covering one concept (e.g. references/data-step/merge.md, references/macros/scope-and-quoting.md). Atoms are populated across both REQUIRED sections (Overview, Critical Rules, Canonical Idioms, Function/Statement Quick Ref, See Also) and OPTIONAL sections (Silent Pitfalls, Anti-patterns). See docs/coverage-matrix.md for per-file status.

What This Skill Does

When activated, Claude Code can:

• Translate study descriptions into idiomatic SAS 9.4 (DATA step, PROC SQL, macros, PROC FREQ/MEANS/LOGISTIC, hash tables, ODS)
• Catch silent-failure patterns before code ships — MERGE overwrite, LAG-inside-IF, missing retain on accumulators, macro-quoting errors, PROC APPEND shape mismatches, and more
• Enforce the 15 rules from sasjs/lint v2.4.3 covering macro definition, file headers, line formatting, and source hygiene
• Apply sasjs/core macro patterns — positional-required + keyword-optional signatures, %local discipline, iftrue= guards, /*/STORE SOURCE*/ registration
• Route to topic-specific reference files for deep dives

Installation

Recommended: Claude Code plugin marketplace

Two slash commands inside any Claude Code session:

/plugin marketplace add xiaosongz/sas94-skill
/plugin install sas94@sas94-skill

Claude Code fetches this repo, installs the sas94 plugin into the local plugin cache, and activates the skill. Update later with:

/plugin marketplace update sas94-skill

Skill activates on .sas files and SAS-flavored prompt keywords — see plugins/sas94/skills/sas94/SKILL.md for the full trigger list.

Alternative: personal-scope git clone

Prefer git over slash commands? Clone the skill subtree into your personal skills directory (one line):

git clone --depth 1 https://github.com/xiaosongz/sas94-skill.git /tmp/sas94-skill && mkdir -p ~/.claude/skills && mv /tmp/sas94-skill/plugins/sas94/skills/sas94 ~/.claude/skills/sas94 && rm -rf /tmp/sas94-skill

Update later by re-running the same command. The plugin marketplace path is cleaner — use it unless you have a reason not to.

Ad-hoc: claude --add-dir <path>

Power-user invocation for one-off skill loading. Clone the repo anywhere, then:

claude --add-dir /path/to/sas94-skill/plugins/sas94/skills/sas94

Claude Code treats that path as an additional skill root for the session only.

Usage

Example prompts

Write a SAS macro that returns an unused libref name, following sasjs/core
conventions.

Merge two claims datasets by member_id; both carry a `paid_amt` column —
make sure the left-side value is preserved.

Review my macro for %local discipline and quote-function usage.

Help me debug a PROC APPEND that errors with "Variable X in DATA set not in
BASE set."

Write a DATA step that computes a lagged diagnosis-date difference, only
for index events.

Contents

sas94-skill/                                      # repo = marketplace
├── .claude-plugin/
│   └── marketplace.json                          # marketplace catalog (lists the sas94 plugin)
├── plugins/
│   └── sas94/                                    # plugin root (copied into ~/.claude/plugins/cache on install)
│       ├── .claude-plugin/
│       │   └── plugin.json                       # plugin manifest
│       └── skills/
│           └── sas94/                            # skill root
│               ├── SKILL.md                      # Thin router — trigger, routing table, workflow
│               ├── assets/
│               │   ├── data-step-template.sas    # DATA step skeleton with Doxygen header
│               │   ├── proc-sql-template.sas     # PROC SQL skeleton
│               │   ├── macro-template.sas        # %macro / %mend skeleton with parenthesized sig
│               │   └── analysis-template.sas     # End-to-end study-program scaffold
│               └── references/                   # Per-topic atom directories, loaded on-demand per SKILL.md routing table
│                   ├── data-step/                # MERGE/BY, LAG, retain+PDV, APPEND, SQL-vs-MERGE, quoting, file hygiene
│                   ├── macros/                   # %macro/%let, scope+quoting, debugging, %include, %sysfunc/%eval
│                   ├── proc-sql/                 # Joins, dedup, INTO :macvar, CASE, RESET + options
│                   ├── base-procs/               # FREQ, MEANS, UNIVARIATE, SORT, TRANSPOSE, REPORT, PRINT, COMPARE, file I/O
│                   ├── stat-procs/               # LOGISTIC, GLM, MIXED, GENMOD, LIFETEST, PHREG, SURVEYMEANS
│                   ├── hash-tables/              # declare+length, find/check rc, iteration, multidata, idioms
│                   ├── ods-and-output/           # ODS OUTPUT capture, destinations, GRAPHICS, SELECT/EXCLUDE, LISTING
│                   ├── formats-informats/        # PROC FORMAT, put-vs-input, date + numeric formats
│                   ├── functions-dates/          # INTNX/INTCK, construction, datetime parts, date arithmetic
│                   ├── functions-strings/        # concat, parse, clean, case + compare
│                   ├── functions-numeric/        # row aggregates, arithmetic, arrays
│                   └── idioms-from-lexjansen/    # SUGI / SAS Global Forum idioms (hash, SQL, macro)
├── docs/                                         # repo-level docs, not shipped with plugin
│   ├── design.md                                 # Architecture and sourcing strategy
│   ├── CONTRIBUTING.md                           # Reviewer workflow, PR + issue templates
│   ├── rule-provenance.md                        # Auto-generated audit trail (rule → source URL)
│   └── coverage-matrix.md                        # Auto-generated reference-file coverage report
├── evals/                                        # manual transcript-check eval harness
└── pipeline/                                     # extractors + generators for rules/idioms

Critical Rules (Summary)

The top-5 rules below are enforced across every SAS file the skill writes. See the per-topic atoms under plugins/sas94/skills/sas94/references/macros/ and plugins/sas94/skills/sas94/references/data-step/ for the full rule set. SKILL.md's routing table is the authoritative entry point for mapping a task to the right atoms.

#	Rule	Reference
1	LOGISTIC models P(Y = lowest ordinal value) by default — pin the event with descending or event='value'	stat-procs.md §Rule 2
2	GENMOD defaults to DIST=NORMAL LINK=IDENTITY — specify both for logistic, Poisson, or gamma	stat-procs.md §Rule 3
3	MERGE silently overwrites same-named columns — rename on input, then coalesce	data-step.md §MERGE overwrite
4	LAG is queue-based — call unconditionally, gate usage afterwards	data-step.md §LAG trap
5	Every %macro must carry parentheses (); declare %local for every non-parameter symbol	macros.md §Rule 1

Full rule list with CORRECT / WRONG code examples and source URLs: docs/rule-provenance.md.

Evaluation

A small regression-baseline eval lives in evals/. Three prompts, one per claimed differentiator of the skill vs. a generic LLM writing SAS (sasjs/core macro conventions, PROC APPEND silent-failure patterns, PROC LOGISTIC event pinning + ODS OUTPUT). The harness is manual — the maintainer runs each prompt inside a fresh Claude Code session with the skill installed, saves Claude's reply to evals/transcripts/<id>.txt, then a stdlib-only Python runner pattern-checks the transcripts. No API key, no SDK dependency, no per-run cost.

Run before tagging a new version:

uv --directory pipeline run python ../evals/run_evals.py

See docs/EVALS.md for why it's a manual harness and evals/README.md for the full how-to.

Contributing

See docs/CONTRIBUTING.md for the reviewer workflow, PR template, and issue template for rule disputes. Content contributions to plugins/sas94/skills/sas94/references/*.md are the primary contribution path — every new Rule or Idiom must carry a Source: URL on the line immediately following the heading.

For pipeline internals — how rules and idioms are sourced, how to refresh SAS-doc scrapes at a new Mx release, how to add a new lexjansen paper, and how to reuse the pattern for other under-represented-language skills — see docs/BUILDING.md.

License

MIT