ASD-STE100 Skill — Simplified Technical English for Agent Output
A universal AI skill that rewrites dense, ambiguous English into ASD-STE100 Simplified Technical English (STE) — the controlled-language standard the aerospace and defense industry built so aircraft maintenance instructions cannot be misread. Its Markdown instructions work with any AI tool that can load them.
This skill repurposes that same discipline for a different reader: an AI agent parsing another agent’s output, a tool description, an error message, or an inter-agent instruction, with no human in the loop to resolve ambiguity.
Why STE, and Why for Agents
STE exists because a misread instruction on an aircraft can kill people, and the intended readers were often not native English speakers with no author to call for clarification. The standard’s fix: one meaning per word, active voice, simple tenses, one instruction per sentence, short sentences, no dropped words.
An LLM agent parsing another agent’s output is in a strikingly similar position — no back-channel, no way to ask “did you mean X or Y?” The same rules that keep a mechanic from misreading a torque spec keep a downstream agent from misreading a tool description or an inter-agent message.
Before / After
| Before | After |
|---|---|
| “This tool will attempt to synchronize state across the various backends that have been configured, and if a conflict is detected it may resolve it automatically depending on the strategy that has been set, or otherwise it will surface the conflict for manual review.” | “The tool synchronizes state across the configured backends. If it finds a conflict, it checks the current strategy. If the strategy allows automatic resolution, the tool resolves the conflict. If not, the tool reports the conflict for manual review.” |
| “An error may have occurred while processing your request due to a possible mismatch in the expected data format, which could be caused by an outdated client version.” | “The request failed. The data format did not match what the server expected. Check your client version — an outdated client is the most common cause.” |
More examples, including illustrations of the official STE rules themselves, in examples/before-after.md.
What This Skill Does
- Picks a mode — Strict for procedures, error messages, and tool descriptions; STE-flavored for READMEs, PR descriptions, and explanatory prose, which keeps the sentence discipline but not the fixed-vocabulary lockdown.
- Reads the input English text for meaning.
- Flags every rule violation sentence-by-sentence: ambiguous word choice, present-perfect/complex tense, passive voice with an unclear actor, multi-instruction sentences, oversized noun clusters, dropped words, sentences over length, phrasal verbs, nominalized actions, semicolons, hedge stacks, and marketing adjectives.
- Rewrites each flagged sentence — without dropping any fact, condition, or scope qualifier from the original. If a shorter phrasing would lose required precision, it keeps the longer phrasing and flags the trade-off instead of silently simplifying.
- Outputs the rewritten text on its own — no preamble, no mode announcement, no change summary — plus a one-line
Kept as-is:note when it deliberately left something unsimplified.
Ask for the reasoning (“show the diff”, “which rules did it break”) and it outputs a before/after table naming each rule instead.
The structural rules it checks are mechanical — you can point at the word or punctuation mark that breaks each one. The rules that depend on ASD’s dictionary are flagged as advisory rather than enforced, and the rules that need taste are left to you.
It does not reproduce ASD’s official ~900-word approved dictionary. The standard is free to obtain but not free to redistribute: Issue 9 permits reproduction only with ASD’s written authority, or by eight listed categories of organisation that this project does not belong to. This skill applies the underlying principle (plainest available word, used the same way every time) rather than checking against a fixed word list. For certified STE-compliant documentation, use the real standard.
Full rule summary and citations: references/writing-rules.md.
Installation
Download the skill package from AI.Tedt.org. You can also download it directly:
curl -fL https://ai.tedt.org/bundles/asd-ste100.zip -o asd-ste100.zipExtract the archive into your AI tool’s configured skills directory, or load
SKILL.md and its included reference files as instructions. Keep the bundled
folder structure and LICENSE file intact. The skill does not require a
specific AI provider or application.
Usage
Trigger with a request to simplify or clarify English text:
Disambiguate this tool description
Rewrite this error message so an agent can't misparse it
Apply ASD-STE100 to this instructionOr paste text and ask your AI tool to “disambiguate this” / “apply STE100 to this” / “reduce ambiguity in this output.”
You get the rewritten text back and nothing else. To see which rules were applied, add “show the diff” or “explain the changes” to the request.
Scope
Built for: agent-to-agent messages, tool/function descriptions, error messages, system prompts, inter-agent instructions — any English text a machine or non-native reader has to parse without a human to ask.
Not built for: creative writing, marketing copy, or anything where voice and nuance are the point — STE is deliberately flat and literal by design.
One limit worth stating up front: this fixes the form of a text, not its substance. A paragraph with nothing to say comes out short, clean, and still empty.
Sources
- ASD-STE100 official site
- ASD-STE100 — About STE
- ASD Europe — Simplified Technical English
- Simplified Technical English — Wikipedia
- TechScribe — ASD-STE100 Simplified Technical English
License
MIT — see LICENSE.
