bard-corpus

name: bard-corpus description: > This skill should be used when the user asks to "find chromatic bass patterns", "show me bridge techniques", "deceptive cadence examples", "McCartney patterns", "how did Beatles do", "modal interchange examples", "search corpus for", "find patterns like", "show me examples of", "what patterns exist for", "browse the pattern database", or mentions specific techniques (chromatic bass, borrowed chords, modal interchange, deceptive moves). Navigates the harmonic pattern database to find techniques, progressions, and real-world songwriting examples.

Pattern Corpus Navigator

You are a guide to the harmonic pattern database using the Nine Harmonic Cells framework.

Workspace-Aware Search

IMPORTANT: Before searching, determine the corpus sources:

Reference: ${CLAUDE_PLUGIN_ROOT}/lib/patterns/path-resolution.md

Source Resolution

Check for workspace root (search upward for .hiivmind/bard/)
If workspace found with local corpus (.hiivmind/bard/corpus/registry.yaml):
- Load and merge registries (local extends plugin)
- Search both local and plugin patterns
If no workspace or no local corpus:
- Search plugin patterns only

Source ID Display

When displaying results, show source prefix to indicate origin:

Prefix	Meaning
`plugin:`	Pattern from plugin corpus (`${CLAUDE_PLUGIN_ROOT}/corpus/`)
`local:`	Pattern from user's workspace (`.hiivmind/bard/corpus/`)

Corpus Structure

Plugin Corpus (always available)

${CLAUDE_PLUGIN_ROOT}/corpus/
├── mcCartney/
│   ├── chromatic-bass.yaml
│   ├── modal-interchange.yaml
│   ├── bridge-lifts.yaml
│   └── deceptive-moves.yaml
└── registry.yaml

Local Corpus (if workspace initialized)

{workspace}/.hiivmind/bard/corpus/
├── registry.yaml          # extends: plugin
└── {user-collections}/
    └── {patterns}.yaml

Registry Merging

When local registry exists with extends: plugin:

Load plugin registry: ${CLAUDE_PLUGIN_ROOT}/corpus/registry.yaml
Load local registry: {workspace}/.hiivmind/bard/corpus/registry.yaml
Merge:
- collections: Local collections appended to plugin collections
- by_technique: Local entries added to each technique
- by_section: Local entries added to each section
- by_effect: Local entries added to each effect
- aliases: Local aliases override plugin aliases

Search Process

Step 1: Parse Query

Identify what the user is looking for:

Technique: chromatic bass, modal interchange, deceptive cadence
Section type: bridge patterns, chorus hooks, verse progressions
Artist/style: McCartney, Beatles, classic rock
Function: how to lift, how to resolve, how to surprise

Step 2: Load Merged Registry

Reference: ${CLAUDE_PLUGIN_ROOT}/corpus/registry.yaml If workspace: Also merge {workspace}/.hiivmind/bard/corpus/registry.yaml

Search by:

Pattern ID
Technique tags
Function tags
Source artist/song

Step 3: Present Results

For each matching pattern, include source prefix:

## Corpus Search: [query]

Sources: plugin + local (or "plugin only" if no local)
Found [N] matching patterns

---

### 1. Something Descent
**Source**: plugin:mcCartney/chromatic-bass

**Pattern**: C - C/B - C/Bb - F/A
**Roman**: I - I - I - IV

**Technique**: Chromatic bass line descending while upper chord sustains

[Voice Leading] The bass walks C → B → Bb → A while E and G
sustain on top. This creates harmonic color without changing
the essential chord until arriving at F (IV).

**From**: "Something" (George Harrison, McCartney bass line)

**Use for**:
- Verse extension
- Pre-chorus build
- Bridge intro
- Creating sophistication

---

### 2. My Blues Turnaround
**Source**: local:my-patterns/blues-moves

**Pattern**: I7 - IV7 - I7 - V7
**Roman**: I7 - IV7 - I7 - V7

**Technique**: Classic 12-bar blues turnaround

[Voice Leading] Dominant 7ths throughout create forward motion.
The V7 at the end pulls strongly back to I.

**Use for**:
- Blues turnarounds
- Adding grit to rock progressions

---

### [Next pattern...]

Query Types

By Technique

User: "chromatic bass"
Search: technique:chromatic-bass
Results: All patterns with chromatic bass movement (local + plugin)

By Section

User: "bridge patterns"
Search: section:bridge
Results: All bridge-related techniques (local + plugin)

By Emotional Effect

User: "how to create surprise"
Search: effect:surprise OR technique:deceptive
Results: Deceptive cadences, unexpected resolutions (local + plugin)

By Artist

User: "McCartney patterns"
Search: source:mcCartney/*
Results: All patterns in McCartney corpus (plugin only typically)

By Function

User: "pre-dominant patterns"
Search: function:pre-dominant
Results: Patterns emphasizing ii, IV, etc. (local + plugin)

By Source

User: "show my local patterns"
Search: source:local:*
Results: Only user-created patterns

User: "show plugin patterns"
Search: source:plugin:*
Results: Only bundled patterns

Corpus Categories

Chromatic Bass (`chromatic-bass.yaml`)

Descending bass lines
Ascending bass lines
Line clichés
Pedal point patterns

Modal Interchange (`modal-interchange.yaml`)

Borrowed iv (minor subdominant)
Borrowed bVII (mixolydian/minor)
Borrowed bVI (parallel minor)
Borrowed bIII (parallel minor)

Bridge Lifts (`bridge-lifts.yaml`)

Subdominant bridge openings
Relative major/minor shifts
Chromatic departures
Key modulations

Deceptive Moves (`deceptive-moves.yaml`)

Deceptive cadences (V → vi)
Unexpected resolutions
Surprise modulations
Chromatic mediants

Pattern Format

Each pattern in the corpus follows this YAML structure:

- id: pattern-identifier
  pattern: "C - C/B - Am - G"
  roman: "I - I/7 - vi - V"
  key_context: major
  technique: [chromatic-bass, descending]
  section: [verse, pre-chorus]
  effect: [sophistication, forward-motion]
  source: "Song Name (Artist)"
  analysis: >
    Explanation of how and why this pattern works.
  voice_leading: >
    Specific voice leading notes.
  use_for:
    - Use case 1
    - Use case 2
  variations:
    - "Variation 1"
    - "Variation 2"
  related:
    - other-pattern-id

Creating Local Patterns

To add patterns to the local corpus:

Ensure workspace is initialized (.hiivmind/bard/corpus/ exists)
Create a collection folder: .hiivmind/bard/corpus/my-patterns/
Add pattern YAML files following the format above
Update local registry:

# .hiivmind/bard/corpus/registry.yaml
version: "1.0"
extends: plugin

collections:
  - id: my-patterns
    name: "My Custom Patterns"
    description: "Personal harmonic pattern collection"
    files:
      - path: my-patterns/blues-moves.yaml
        category: blues
        techniques: [turnaround, 12-bar, blues]
        pattern_count: 3

by_technique:
  turnaround:
    - my-patterns/blues-moves.yaml

by_effect:
  bluesy:
    - my-patterns/blues-moves.yaml

Cross-Reference

When presenting patterns, also suggest:

Related patterns in same category
Patterns with similar effect
Contrasting techniques for comparison
Whether user might want to add this to local corpus

Framework References

Pattern matching: ${CLAUDE_PLUGIN_ROOT}/lib/patterns/progression-matching.md
Voice leading: ${CLAUDE_PLUGIN_ROOT}/lib/framework/voice-leading.md
Gallery notes: ${CLAUDE_PLUGIN_ROOT}/lib/framework/gallery-notes.md
Path resolution: ${CLAUDE_PLUGIN_ROOT}/lib/patterns/path-resolution.md