pbf: Skill for Claude Code

ASD-STE100 (Simplified Technical English)

"Write it simply" is not enough instruction to produce STE reliably. General prose habits (em dashes, semicolons, nested subordination, metaphor) are strongly trained in. Vague guidance to simplify either overcorrects into choppy, meaningless fragments, or lets those habits back in without the writer noticing. Run the checklist below explicitly, sentence by sentence. Do not rely on a general sense of "simple."

What the checklist contains, and why it has three parts

Part A paraphrases the rules of the standard itself. ASD-STE100 is a controlled language built by the aerospace and defense industry so that a technician on a tarmac, with no author to call, cannot misread an instruction. Issue 9 (January 2025) has 53 rules in 9 sections, plus a dictionary of about 900 approved words. See references/writing-rules.md for the fuller summary and the sources.

Part B names failure modes the standard never had to name, because its authors were not language models. An em dash joining two clauses, a semicolon chaining independent assertions, a spatial metaphor for an abstract relation: these are trained-in habits, and a rule list that omits them will pass text that no human STE editor would pass.

Part C protects meaning. Every rule in Parts A and B can be satisfied by a rewrite that says something the original did not say. Style conformance and meaning fidelity are independent failure modes, and Part C is the only one of the three that catches the second.

A pass that applies Part A alone under-detects. A pass that applies Part C alone leaves violations in place. Both were observed in a real head-to-head run of two earlier versions of this skill.

Two situations, two risk profiles

Drafting new prose in STE is lower risk. Apply the checklist as you write. Self-check before calling a passage done.

Converting existing prose to STE is higher risk, because the goal is not just STE-conformant text. It is text that means exactly what the original meant.