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.
git clone --depth 1 https://github.com/danielvm-git/bigpowersWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/rules/danielvm-git/bigpowers/define-language)<a href="https://agentmods.dev/rules/danielvm-git/bigpowers/define-language"><img src="https://agentmods.dev/badge/rules/danielvm-git/bigpowers/define-language/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/rules/danielvm-git/bigpowers/define-language"><img src="https://agentmods.dev/badge/rules/danielvm-git/bigpowers/define-language.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00068 | $0.00854 |
| Opus 5.5 | $0.00027 | $0.00342 |
| Sonnet 5.5 | $0.00014 | $0.00171 |
| Haiku 4.5 | $0.00007 | $0.00085 |
Grade A, and why
define-language 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 1mo 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.
How it starts
The opening of the file, as written. The whole thing — 80 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Define Language
Extract and formalize domain terminology from the current conversation into a consistent glossary, saved to specs/UBIQUITOUS_LANGUAGE_LATEST.md.
Distinct from model-domain and deepen-architecture: Use this skill to produce a canonical glossary of terms (words and definitions). Use model-domain to stress-test a plan through an interview that resolves domain model decisions. Use deepen-architecture to find module-level refactoring opportunities in the codebase.
HARD GATE — Ubiquitous language is NOT optional. Every term in the domain that could be misunderstood must be glossed. Ambiguity = rework.
Process
- Scan the conversation for domain-relevant nouns, verbs, and concepts
- Identify problems:
- Same word used for different concepts (ambiguity)
- Different words used for the same concept (synonyms)
- Vague or overloaded terms
- Propose a canonical glossary with opinionated term choices
- Write to
specs/UBIQUITOUS_LANGUAGE_LATEST.mdin the working directory using the format below - Output a summary inline in the conversation
Output Format
Write a specs/UBIQUITOUS_LANGUAGE_LATEST.md file with this structure:
# Ubiquitous Language
## Order lifecycle
| Term | Definition | Aliases to avoid |
| ----------- | ------------------------------------------------------- | --------------------- |
| **Order** | A customer's request to purchase one or more items | Purchase, transaction |
| **Invoice** | A request for payment sent to a customer after delivery | Bill, payment request |
## People
| Term | Definition | Aliases to avoid |
| ------------ | ------------------------------------------- | ---------------------- |
| **Customer** | A person or organization that places orders | Client, buyer, account |
| **User** | An authentication identity in the system | Login, account |
## Relationships
- An **Invoice** belongs to exactly one **Customer**
- An **Order** produces one or more **Invoices**
## Example dialogue
> **Dev:** "When a **Customer** places an **Order**, do we create the **Invoice** immediately?"
> **Domain expert:** "No — an **Invoice** is only generated once a **Fulfillment** is confirmed."
## Flagged ambiguities
- "account" was used to mean both **Customer** and **User** — these are distinct concepts.
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.
- 1mo ago First seen · 80 lines · 68 tokens per session scan A 3891b36a5021
define-language is a cursor rule published in the GitHub repository danielvm-git/bigpowers (267 stars, last pushed 27d ago), licensed MIT. It adds 68 tokens to every session and 854 once invoked, about $0.0003 per session on Opus 5.5. 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 2026-09-03.
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