npx skills add majiayu000/claude-skill-registry --skill postel --agent claude-code
Same command for any agent — swap --agent for codex, cursor, copilot.
Weekly change comes from our own snapshots, not the repository page — it measures attention, not adoption.
# POSTEL — The Robustness Principle > *"Be conservative in what you send, liberal in what you accept."* > — Jon Postel, RFC 761 (1980) --- ## What Is It? **POSTEL** is how MOOLLM handles ambiguity, errors, and incomplete instructions: Instead of failing, **find the best possible interpretation** that: 1. Accomplishes the likely intent 2. Respects stated constraints 3. Preserves user autonomy 4. Fails gracefully if truly impossible **Also known as:** - The Robustness Principle - Postel's Law - Best Possible Interpretation Protocol - Charitable Interpretation - Be liberal in what you accept --- ## The Protocol When faced with ambiguity: ``` 1. GATHER context — what do we know? 2. INFER intent — what did they probably mean? 3. PROPOSE interpretation — state your understanding 4. ACT constructively — do the reasonable thing 5. REPORT uncertainty — flag what you assumed ``` --- ## Examples ### Ambiguous Command **Input:** `"delete the old files"` **POSTEL Response:** ``` I interpret "old files" as files not modified in 30+ days. Found 12 candidates in ./temp/ Before deleting, I'll: 1. List them for your review 2. Move to trash (not permanent delete) 3. Wait for confirmation Proceed? [Y/
- What Is It?
- The Protocol
- Examples
- Ambiguous Command
- Incomplete Data
- Contradictory Instructions
- Core Principles
- Jon Postel's Original Formulation
- Charity
- Transparency
- When to Invoke
- Anti-Patterns
- Jon Postel (1943-1998)
- Dovetails With
What does the postel skill do?
Be conservative in what you send, liberal in what you accept.
How do I install it?
Run `npx skills add majiayu000/claude-skill-registry --skill postel --agent claude-code` — it drops the skill into your project so the agent can pick it up. Swap the --agent value for codex, cursor or copilot if you use one of those.
Where does this skill come from?
From majiayu000/claude-skill-registry, a repository with 534 stars. We read it straight from the repository tree rather than a submitted listing, so what you see here is what is actually published.
Is a popular skill a good skill?
Not necessarily. Stars measure attention, not adoption — a repository can trend for a week and be abandoned. That is why we show the weekly change from our own snapshots next to the total, instead of a single flattering number.