large-doc-mastery

name	large-doc-mastery
description	Large document and codebase synthesis skill. Activates when the user provides 50k–200k+ tokens of context — codebases, PDFs, legal documents, transcripts, research corpora — and needs synthesis, cross-referencing, or insight extraction with perfect recall across the entire context. Not a summarizer. A precision instrument for finding patterns, contradictions, dependencies, and insights that only emerge when you hold the whole thing at once. Use when user says: analyze this codebase, read this whole document, find all references to X, synthesize across sections, what does this say about Y, find contradictions, extract all decisions, map the dependencies, read the whole thing, cross-reference, audit the entire document, what changed between sections, find every mention of, trace this through the code, what's missing. Do NOT activate for: small documents where a direct answer is more useful, tasks that don't require cross-document reasoning. First response: "Large Document Mode active. Paste or attach your document(s). Tell me the synthesis goal — what insight, decision, or structure you're after."
license	Apache 2.0

Large Document / Codebase Mastery

Summaries lose information. "Analyze this 80k-token codebase" with no structure produces a vague paragraph about architecture that misses the three critical bugs and the two deprecated modules that half the new code still imports.

The skill is not consuming large context — Claude does that automatically. The skill is structuring the task so the synthesis is precise: specific questions, specific output formats, explicit cross-reference instructions, and verification passes that confirm the model used the actual document rather than its priors.

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SLASH COMMANDS

Command	Action
/map	Build a structural map of the document (sections, components, entities)
/index <topic>	Find every location in the document that touches a specific topic
/extract <type>	Extract all instances of a type: decisions, risks, assumptions, TODOs, etc.
/cross-ref <a> <b>	Find all connections between two topics, sections, or entities
/contradictions	Surface any internal contradictions or inconsistencies in the document
/gaps	Identify what's absent — what the document should address but doesn't
/trace <entity>	Follow an entity (function, concept, person, requirement) through the full document
/timeline	Extract a chronological sequence of events, changes, or decisions
/compare <section-a> <section-b>	Directly compare two sections or files
/synthesize <question>	Answer a specific question using the full document as context
/verify <claim>	Check whether a specific claim is supported by the document
/hotspots	Identify the highest-complexity or highest-risk areas
/summary-lossy	Produce a short summary with explicit list of what was dropped

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HIGH-LEVEL WORKFLOW

User provides large document / codebase
    │
    ├─ Phase 1: Document Orientation
    │     Build structural map; identify key entities and sections
    │
    ├─ Phase 2: Scope Definition
    │     Clarify the synthesis goal — don't analyze everything equally
    │
    ├─ Phase 3: Targeted Extraction
    │     Pull specific patterns, entities, or facts with location references
    │
    ├─ Phase 4: Cross-Reference Pass
    │     Connect extracted elements across sections or files
    │
    ├─ Phase 5: Synthesis
    │     Answer the synthesis question with evidence citations
    │
    └─ Phase 6: Verification
          Confirm claims are in the document, not in prior knowledge

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PHASE 1 — DOCUMENT ORIENTATION

Before any analysis, build an orientation map. This prevents anchor bias — where the first section dominates the analysis and the rest is skimmed.

Orientation map format

DOCUMENT MAP: [title / description]
Total scope: [estimated sections / files / pages]

STRUCTURE
  [Section/File 1]: [1-line description] — [key entities defined]
  [Section/File 2]: [1-line description] — [key entities defined]
  ...

KEY ENTITIES
  [Entity type]: [list] — (e.g., Functions, Classes, Requirements, Actors)

DENSITY DISTRIBUTION
  Heavy:    [sections with most content / complexity]
  Light:    [sections with least content]
  Missing:  [sections referenced but absent]

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PHASE 2 — SCOPE DEFINITION

Large documents contain far more than any single analysis needs. Before extracting, define the synthesis aperture — what lens is this analysis using?

Synthesis aperture types

Aperture	Question being answered	Best for
Decision audit	What decisions were made, by whom, and why?	Meeting transcripts, PRDs, ADRs
Risk surface	What can go wrong, and where?	Architecture docs, contracts, plans
Dependency map	What depends on what?	Codebases, system designs
Consistency check	Does the document contradict itself?	Legal docs, specs, policies
Entity trace	How does X evolve through the document?	Code, narratives, regulations
Gap analysis	What's missing that should be here?	Requirements, audits
Change surface	What changed between versions / sections?	Diffs, revisions, amendments

Scope question rules

• Ask ONE scope-defining question if the synthesis goal is ambiguous
• If the user says "analyze everything," default to: Risk surface + Dependency map
• Never attempt all apertures simultaneously — output becomes noise

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PHASE 3 — TARGETED EXTRACTION

Extract with location anchors. Every extracted element must cite where it came from.

Extraction format

EXTRACTION: [type] — [aperture]

[ID]. [Extracted element]
     Location: [section / file / line / page]
     Context:  [1 sentence: surrounding context that makes this significant]
     Flags:    [RISK | DECISION | ASSUMPTION | TODO | CONTRADICTION | DEPENDENCY]

Extraction rules

• Cite location for every item. Uncited extractions cannot be verified.
• Do not paraphrase. Quote directly, then interpret in the Context field.
• Flag before filtering. Extract everything matching the type, then rank.
• Note absences. If a required element (e.g., error handling, auth check) is absent, flag as MISSING.
• Distinguish document claims from your inferences. Use "The document states..." vs "This implies..."

High-value extraction targets by document type

Document type	High-value extraction targets
Codebase	TODO/FIXME, dead code, circular deps, missing error handling, hardcoded values
Legal / contract	Obligations, conditions, termination clauses, liability caps, ambiguous definitions
PRD / spec	Unverified assumptions, missing acceptance criteria, conflicting requirements
Research / report	Methodology limitations, sample sizes, confidence intervals, conflicting findings
Architecture doc	Single points of failure, unstated assumptions, missing components

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PHASE 4 — CROSS-REFERENCE PASS

The insight that justifies large-context analysis only appears when you connect elements that are far apart in the document.

Cross-reference format

CROSS-REFERENCE: [entity A] ↔ [entity B]

Connection 1:
  [Entity A] location: [cite]
  [Entity B] location: [cite]
  Relationship: [DEPENDS_ON | CONTRADICTS | MODIFIES | REFERENCES | UNDEFINED]
  Significance: [1 sentence: why this connection matters]

Connection 2:
  ...

SUMMARY
  Total connections found: [N]
  Critical connections (high-risk or decision-affecting): [list]
  Unresolved: [connections implied but not made explicit in the document]

Cross-reference rules

• Always cite both locations — without both citations, the connection cannot be verified
• CONTRADICTS always surfaces first — contradictions are the highest-value finding
• UNDEFINED means the relationship exists but the document doesn't specify it — flag these

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PHASE 5 — SYNTHESIS

Answer the synthesis question using the extracted and cross-referenced evidence.

Synthesis output format

SYNTHESIS: [question / aperture]

FINDING
[Direct answer in 1–3 sentences]

EVIDENCE
1. [claim] — Source: [location]
2. [claim] — Source: [location]
3. [claim] — Source: [location]

PATTERNS
[Cross-document pattern that only appears with full context]

ANOMALIES
[Elements that don't fit the pattern; outliers; exceptions]

CONFIDENCE
[HIGH / MEDIUM / LOW] — [1 sentence: what limits confidence]

WHAT'S NOT IN THE DOCUMENT
[What the synthesis question required but the document doesn't contain]

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PHASE 6 — VERIFICATION

After synthesis, run a verification pass to confirm the output is document-grounded.

Verification checklist

For each major claim in the synthesis:

• Can I cite the exact location in the document where this appears?
• Am I paraphrasing accurately, or am I inferring beyond what's stated?
• Is this in the document, or is it from my training data?
• If I'm connecting two things, are both connections cited?

Verification format

VERIFICATION PASS

Claim: "[claim from synthesis]"
  Status: DOCUMENT-GROUNDED | INFERENCE | TRAINING KNOWLEDGE
  Citation: [location, or NONE]
  Note: [if inference or training knowledge: flag for user review]

Common verification failures in large-context tasks

Failure	Signal	Fix
Prior contamination	Claim is true but not in the document	Flag as TRAINING KNOWLEDGE
Location drift	Cited location doesn't contain the claim	Re-read and re-cite
Paraphrase inflation	Summary adds meaning the original doesn't have	Quote directly
Recency bias	Last section dominates synthesis	Re-run extraction on early sections
Gap hallucination	Document "says" something it actually omits	Add to WHAT'S NOT IN THE DOCUMENT