bluebook
This skill should be used when the user asks to “cite a case”, “format a citation”, “check Bluebook format”, “cite a statute”, “use id. or supra”, “format footnotes”, “cite a law review article”, or needs Bluebook 21st Edition citation guidance.
Best use case
bluebook is best used when you need a repeatable AI agent workflow instead of a one-off prompt.
This skill should be used when the user asks to “cite a case”, “format a citation”, “check Bluebook format”, “cite a statute”, “use id. or supra”, “format footnotes”, “cite a law review article”, or needs Bluebook 21st Edition citation guidance.
Teams using bluebook should expect a more consistent output, faster repeated execution, less prompt rewriting.
When to use this skill
- You want a reusable workflow that can be run more than once with consistent structure.
When not to use this skill
- You only need a quick one-off answer and do not need a reusable workflow.
- You cannot install or maintain the underlying files, dependencies, or repository context.
Installation
Claude Code / Cursor / Codex
Manual Installation
- Download SKILL.md from GitHub
- Place it in
.claude/skills/bluebook/SKILL.mdinside your project - Restart your AI agent — it will auto-discover the skill
How bluebook Compares
| Feature / Agent | bluebook | Standard Approach |
|---|---|---|
| Platform Support | Not specified | Limited / Varies |
| Context Awareness | High | Baseline |
| Installation Complexity | Unknown | N/A |
Frequently Asked Questions
What does this skill do?
This skill should be used when the user asks to “cite a case”, “format a citation”, “check Bluebook format”, “cite a statute”, “use id. or supra”, “format footnotes”, “cite a law review article”, or needs Bluebook 21st Edition citation guidance.
Where can I find the source code?
You can find the source code on GitHub using the link provided at the top of the page.
SKILL.md Source
# Bluebook 21st Edition Citation
Citation formatting for law reviews and legal scholarship per *The Bluebook: A Uniform System of Citation* (21st ed. 2020).
**Announce:** “I’m using the bluebook skill for citation formatting.”
## When to Use
Invoke this skill for:
- Formatting case citations (federal, state, foreign)
- Statutory and regulatory citations
- Secondary sources (books, articles, treatises)
- Short form citations (id., supra, hereinafter)
- Introductory signals and parentheticals
- Citation sentences vs. citation clauses
**For legal writing style**: Use `/writing-legal` skill (Volokh)
**For general writing**: Use `/writing` skill (Strunk & White)
<EXTREMELY-IMPORTANT>
## IRON LAW #1: NO CITATION WITHOUT VERIFICATION
**If you haven’t verified EVERY element of a citation, DO NOT write it.**
Before writing ANY citation:
1. Verify case name spelling and procedural posture
2. Verify reporter volume and page numbers
3. Verify court and year
4. Verify pinpoint page exists
**Guessing reporter volumes or page numbers is NOT HELPFUL — the user publishes with wrong citations that fail verification. Period.**
</EXTREMELY-IMPORTANT>
<EXTREMELY-IMPORTANT>
## IRON LAW #2: NO SHORT FORMS WITHOUT FULL CITATION FIRST
**Id., supra, and hereinafter REQUIRE a preceding full citation.**
Before using ANY short form:
1. Locate the full citation in the document
2. Verify no intervening citations (for id.)
3. Verify the supra reference is unambiguous
**Using id. after intervening citations creates ambiguity. Delete and cite in full.**
</EXTREMELY-IMPORTANT>
<EXTREMELY-IMPORTANT>
## IRON LAW #3: FOOTNOTE VS. TEXT CITATION FORMAT
**Law review citations use footnote format (Rule 1). Court documents use text format (Bluepages).**
```
FOOTNOTE (law reviews): Smith v. Jones, 500 U.S. 1, 5 (1991).
TEXT (court documents): Smith v. Jones, 500 U.S. 1, 5 (1991)
FOOTNOTE (statutes): 18 U.S.C. § 1001 (2018).
TEXT (statutes): 18 U.S.C. § 1001 (2018)
```
**If writing for a law review and using text format conventions, DELETE and reformat.**
</EXTREMELY-IMPORTANT>
## The Gate Function
Before writing ANY citation:
```
1. IDENTIFY → What type of source? (case, statute, article, book)
2. LOCATE → Find the correct rule in Bluebook
3. VERIFY → Confirm ALL elements (volume, page, court, year)
4. FORMAT → Apply correct typeface and punctuation
5. CHECK → Does this match examples in the rule?
6. WRITE → Only after steps 1-5
```
**Skipping any step produces unreliable citations.**
## Citation Facts
- An intervening citation breaks *id.* — *id.* after an intervening cite is ambiguous and must become a full short form. *Supra* only works when the full citation it points to actually exists earlier in the document.
- Signals are checked against Rule 1.2 examples, not intuition — a wrong signal misleads the reader about how the source supports the proposition.
- Parentheticals explain the source's relevance; pinpoints prove the specific claim. A cite deferred ("I'll add the pinpoint later") ships without one.
- Typeface (Rule 2) is mandatory, not stylistic. Abbreviations come from tables T6, T10, T12 — "common" or "obvious" abbreviations that don't match the tables fail cite-check.
- "Pretty sure" about a reporter volume or page number means unverified — a guessed element presented as a citation is an unverified claim, and exact pinpoints are required.
## Quick Reference: Common Citation Forms
### Cases (Rule 10)
```
Full citation:
Brown v. Board of Education, 347 U.S. 483, 495 (1954).
Short form (same footnote or five footnotes with no intervening):
Id. at 496.
Short form (different footnote, no intervening):
Brown, 347 U.S. at 497.
Short form (intervening citations):
Brown v. Board of Education, 347 U.S. at 498.
```
### Statutes (Rule 12)
```
Full citation:
42 U.S.C. § 1983 (2018).
Multiple sections:
42 U.S.C. §§ 1983-1985 (2018).
Short form:
§ 1983 or id. § 1984
```
### Law Review Articles (Rule 16)
```
Full citation:
Cass R. Sunstein, *On the Expressive Function of Law*, 144 U. Pa. L. Rev. 2021, 2030 (1996).
Short form:
Sunstein, supra note 12, at 2035.
```
### Books (Rule 15)
```
Full citation:
Richard A. Posner, Economic Analysis of Law 45 (9th ed. 2014).
Short form:
Posner, supra note 5, at 52.
```
## Typeface Rules (Rule 2)
| Source Type | Law Review Format |
|-------------|-------------------|
| Case names | Italics: *Brown v. Board* |
| Book titles | Small caps: ECONOMIC ANALYSIS OF LAW |
| Article titles | Italics: *On the Expressive Function* |
| Journal names | Small caps: U. PA. L. REV. |
| Periodical names (non-consecutively paginated) | Italics: *N.Y. Times* |
| Statutes | Roman: 42 U.S.C. § 1983 |
## Introductory Signals (Rule 1.2)
| Signal | Meaning | Use When |
|--------|---------|----------|
| [no signal] | Direct support | Source directly states proposition |
| *See* | Implicit support | Source supports but doesn’t directly state |
| *See, e.g.,* | One of several | Multiple sources support; citing representative |
| *Cf.* | Analogous support | Source supports by analogy |
| *Compare* ... *with* | Comparison | Sources illustrate through contrast |
| *See generally* | Background | Source provides helpful background |
| *But see* | Contradiction | Source contradicts proposition |
| *Contra* | Direct contradiction | Source directly contradicts |
### Signal Order (Rule 1.3)
Within a single citation sentence, signals appear in this order:
1. [no signal]
2. *E.g.,*
3. *Accord*
4. *See*
5. *See also*
6. *Cf.*
7. *Compare*
8. *Contra*
9. *But see*
10. *But cf.*
11. *See generally*
## Common Errors Checklist
### Case Citations
- [ ] Party names shortened properly (omit “Inc.”, “Ltd.” unless only identifier)
- [ ] “United States” abbreviated to “U.S.” (as party, not “United States of America”)
- [ ] Reporter abbreviation matches T1
- [ ] Court identifier included unless obvious from reporter
- [ ] Year is decision year, not argument year
- [ ] Pinpoint included for specific propositions
### Statutory Citations
- [ ] Current official code used (not session laws for current statutes)
- [ ] Section symbol (§) used, not “Section”
- [ ] Space between § and number
- [ ] Year is code edition year, not enactment year
- [ ] Supplements cited when applicable
### Short Forms
- [ ] Full citation appears earlier in same document
- [ ] Id. used only when no intervening citation
- [ ] Supra refers to footnote number where full cite appears
- [ ] Hereinafter defined in first full citation
## Progressive Disclosure
For detailed rules, consult:
### Reference Files
- **`references/cases.md`** - Complete case citation rules (R. 10)
- **`references/statutes.md`** - Statutory and regulatory citations (R. 12-14)
- **`references/secondary-sources.md`** - Books, articles, treatises (R. 15-17)
- **`references/short-forms.md`** - Id., supra, hereinafter rules (R. 4)
- **`references/signals-parentheticals.md`** - Signals, parentheticals, order (R. 1)
- **`references/audit-patterns.md`** - Citation audit patterns and validation
- **`references/abbreviations.md`** - Bluebook abbreviation tables
### NotebookLM Integration
For edge cases, ambiguous rules, or additional context beyond the reference files, query the Bluebook 21e (2020) notebook:
```bash
# Notebook ID: f70a9976-b443-43d5-b5fd-43ff86b2b700
# Query specific Bluebook rules
/Users/vwh7mb/projects/nlm/nlm generate-chat f70a9976-b443-43d5-b5fd-43ff86b2b700 “How do I cite an unpublished opinion under Rule 10.8.1?”
# Get rule clarification
/Users/vwh7mb/projects/nlm/nlm generate-chat f70a9976-b443-43d5-b5fd-43ff86b2b700 “What are the typeface conventions for treaty citations?”
# Verify abbreviation tables
/Users/vwh7mb/projects/nlm/nlm generate-chat f70a9976-b443-43d5-b5fd-43ff86b2b700 “What is the correct abbreviation for ‘Environmental’ in journal names per Table T13?”
```
**When to query the notebook:**
- Rule wording is ambiguous in reference files
- Formatting international or specialized materials
- Checking obscure abbreviations not in quick reference
- Resolving conflicts between rules
- Understanding historical changes from previous editions
### When to Load References
Load the specific reference when:
- Formatting an unfamiliar source type
- Encountering edge cases (unpublished cases, foreign sources)
- Checking state-specific reporter requirements
- Working with complex statutory schemes
- Formatting international materials
## Integration
Use with `/writing-legal` for complete legal scholarship workflow:
1. `/bluebook` formats citations correctly
2. `/writing-legal` ensures argument structure and evidence handling
3. `/ai-anti-patterns` catches AI writing indicators before submission
## Delete & Restart Pattern
**When to delete and restart:**
1. **Citation uses guessed page numbers** → Delete, verify source, cite with real numbers
2. **Id. follows intervening citation** → Delete id., use full short form
3. **Wrong signal used** → Delete, reread Rule 1.2, apply correct signal
4. **Typeface incorrect** → Delete, apply Rule 2 typeface
5. **Abbreviation doesn’t match Bluebook tables** → Delete, use table abbreviation
**How to restart:**
```
Old: See Smith v. Jones, 500 U.S. at 15. Id. at 20. [intervening cite] Id. at 25.
New: See Smith v. Jones, 500 U.S. at 15. Id. at 20. [intervening cite] Smith, 500 U.S. at 25.
```
The third cite cannot use id. after an intervening citation.Related Skills
bluebook-audit
This skill should be used when the user asks to 'audit footnotes', 'check Bluebook formatting', 'audit citations', 'run footnote audit', 'check my footnotes', 'bluebook audit', or needs systematic Bluebook compliance checking of a law review manuscript.
writing
This skill should be used when the user asks to 'write a paper', 'start a writing project', 'draft an article', 'write about', 'brainstorm writing topics', 'gather sources for a paper', 'what should I write about', or needs the writing workflow entry point for any writing task.
writing-validate
Validate draft sections cover all PRECIS claims before review.
writing-setup
Internal skill for creating PRECIS.md, OUTLINE.md, and ACTIVE_WORKFLOW.md. Called after brainstorm sources are gathered.
writing-revise
This skill should be used when the user asks to 'revise writing', 'fix review issues', 'polish draft', 'apply review feedback', 'complete writing workflow', or after /writing-review produces REVIEW.md with issues to fix.
writing-review
Internal skill for hierarchical document review. Called by writing-validate after claim validation passes.
writing-precis-reviewer
Internal skill used by writing-setup at exit gate. Dispatches a reviewer subagent to verify PRECIS.md quality before outlining. NOT user-facing.
writing-outline
Internal skill for creating detailed section outlines. Called by /writing workflow after PRECIS and master OUTLINE are complete.
writing-outline-reviewer
Internal skill used by writing-outline at exit gate. Dispatches a reviewer subagent to verify OUTLINE.md quality before drafting. NOT user-facing.
writing-lit-review
Internal skill for literature review and source materialization. Called after brainstorm, before setup. NOT user-facing.
writing-legal
Internal skill for academic legal writing. Loaded by /writing when style=legal. Based on Volokh's "Academic Legal Writing".
writing-handoff
Create structured handoff document for writing workflow session pause/resume.