Arch Lens Repository Access

Repository/Data Access Architecture Lens

Cognitive Mode: Data-Centric Primary Question: "How is data accessed?" Focus: Repository Pattern, Entity Relationships, Query Patterns, Format Conversion

When to Use

• Need to understand data access layer architecture
• Documenting repository pattern implementation
• Analyzing entity relationships and query patterns
• User invokes /autoskillit:arch-lens-repository-access or /autoskillit:make-arch-diag repository

Critical Constraints

NEVER:

• Modify any source code files
• Focus on data flow (that's data lineage lens)
• Include business logic details
• Run subagents in the background (run_in_background: true is prohibited)

ALWAYS:

• Focus on REPOSITORIES and their methods
• Show entity relationships (1:1, 1:N, N:N)
• Document key query patterns
• Identify format conversion boundaries
• BEFORE creating any diagram, LOAD the /autoskillit:mermaid skill using the Skill tool - this is MANDATORY
• If the Skill tool cannot be used (disable-model-invocation) or refuses this invocation, do NOT proceed with diagram creation. Abort this step and omit the diagram from output.
• After writing the diagram file, emit the absolute path as a structured output

token as your final output. Resolve the relative temp/arch-lens-repository-access/... save path to absolute by prepending the full CWD: `` diagram_path = /absolute/cwd/temp/arch-lens-repository-access/{filename}.md `` This token is MANDATORY — the pipeline cannot proceed without it.

Arguments

/autoskillit:arch-lens-repository-access [context_path]

• context_path (optional) — Absolute path to a PR context file containing new files

(★-prefixed) and modified files (●-prefixed) from the PR diff. When provided, read this file before beginning analysis and focus the diagram on the architectural areas affected by these specific files. When absent, explore the full CWD.

---

Analysis Workflow

Step 0: Read PR context (when provided)

If a context_path positional argument is present:

1. Read the file at context_path
2. Extract: new files list (★-prefixed), modified files list (●-prefixed)
3. Focus Step 1 exploration on the modules/components these files belong to
4. Apply ★ prefix on diagram nodes representing new files/components
5. Apply ● prefix on diagram nodes representing modified files/components

If no context_path is provided, skip this step and explore the full CWD in Step 1.

Step 1: Launch Parallel Exploration Subagents

Spawn Explore subagents to investigate:

Repository Classes

• Find all repository implementations
• Identify base repository patterns
• Look for: Repository classes, DAO (Data Access Object) patterns, base repository abstractions

Entity Models

• Find entity/model classes
• Identify table/collection definitions
• Look for: ORM models (ActiveRecord, Entity Framework, TypeORM, etc.), data models, entity classes

CRUD Operations

• Find standard CRUD methods
• Identify specialized query methods
• Look for: create, get, update, delete, save, find, getby_, query methods

Query Patterns

• Find complex queries and joins
• Identify index usage patterns
• Look for: filter, where, join, orderby, groupby, query builders

Factory/Scoping

• Find repository factory patterns
• Identify scope management
• Look for: Factory patterns, dependency injection, session/context management

Format Conversion

• Find adapter/converter patterns
• Identify boundary conversions
• Look for: Adapters, DTOs, to/from methods, serializers, mappers

Step 2: Map Entity Relationships

Document:

• Entities: All model classes
• Relationships: Foreign key relationships, cardinality
• Key Fields: Primary keys, business keys
• Repositories: Which repo manages which entity

CRITICAL - Analyze Read/Write Direction: For EVERY repository method and data access:

• Read methods: get_*, find_*, query_* - data flows OUT of storage
• Write methods: save_*, create_*, update_*, delete_* - data flows INTO storage
• Bulk operations: Direction of each operation in batch

For EVERY caller-to-repository relationship:

• Does the caller READ from this repository?
• Does the caller WRITE to this repository?
• Or both?

Label connections accordingly (reads, writes, reads/writes)

Step 3: Document Access Patterns

| Pattern | Repository Method | Use Case | |---------|------------------|----------| | By ID | getbyid() | Single entity lookup | | By Business Key | getby | Domain-specific lookup | | List | getall(), getfor | Collection queries | | Bulk | savemany() | Batch operations |

Step 4: Create the Diagram

Use flowchart with:

Direction: LR (left-to-right) for caller-to-storage flow

Subgraphs:

• Callers (who uses repositories)
• Factory (repository construction)
• Repositories by Category
• Conversion (format boundaries)
• Storage (database tables)

Node Styling:

• cli class: Callers (nodes, handlers)
• phase class: Factory, scoping
• newComponent class: Repositories (green to highlight)
• handler class: Conversion adapters
• integration class: Database storage

Show Relationships:

• Entity relationships with cardinality (1:N)
• Repository-to-table mapping
• Conversion flow

Step 5: Write Output

Write the diagram to: {{AUTOSKILLIT_TEMP}}/arch-lens-repository-access/arch_diag_repository_access_{YYYY-MM-DD_HHMMSS}.md (relative to the current working directory)

After writing the diagram file, emit a structured output line:

> IMPORTANT: Emit the structured output tokens as literal plain text with no > markdown formatting on the token names. Do not wrap token names in **bold**, > *italic*, or any other markdown. The adjudicator performs a regex match on the > exact token name — decorators cause match failure.

diagram_path = {absolute_path_to_diagram_file}

---

Output Template

# Repository/Data Access Diagram: {System Name}

**Lens:** Repository/Data Access (Data-Centric)
**Question:** How is data accessed?
**Date:** {YYYY-MM-DD}
**Scope:** {What was analyzed}

## Repository Overview

| Category | Count | Key Repositories |
|----------|-------|------------------|
| {category} | {N} | {names} |

## Data Access Diagram

```mermaid
%%{init: {'flowchart': {'nodeSpacing': 50, 'rankSpacing': 60, 'curve': 'basis'}}}%%
flowchart LR
    %% CLASS DEFINITIONS %%
    classDef cli fill:#1a237e,stroke:#7986cb,stroke-width:2px,color:#fff;
    classDef stateNode fill:#004d40,stroke:#4db6ac,stroke-width:2px,color:#fff;
    classDef handler fill:#e65100,stroke:#ffb74d,stroke-width:2px,color:#fff;
    classDef phase fill:#6a1b9a,stroke:#ba68c8,stroke-width:2px,color:#fff;
    classDef output fill:#00695c,stroke:#4db6ac,stroke-width:2px,color:#fff;
    classDef integration fill:#c62828,stroke:#ef9a9a,stroke-width:2px,color:#fff;
    classDef newComponent fill:#2e7d32,stroke:#81c784,stroke-width:2px,color:#fff;

    subgraph Callers ["CALLERS"]
        CALLER1["Handler/Service━━━━━━━━━━Business logic"]
    end

    subgraph Factory ["REPOSITORY FACTORY"]
        direction TB
        FAC["RepositoryFactory━━━━━━━━━━Dependency injection"]
        SCOPE["Scoping━━━━━━━━━━Context management"]
    end

    subgraph Repositories ["REPOSITORIES"]
        direction TB
        REPO1["EntityRepository━━━━━━━━━━CRUD methods"]
        BASE["BaseRepository━━━━━━━━━━Generic CRUD"]
    end

    subgraph Conversion ["FORMAT CONVERSION"]
        direction TB
        ADAPTER["Adapters/DTOs━━━━━━━━━━Serialization"]
    end

    subgraph Storage ["DATABASE"]
        direction TB
        DB[("Table/Collection━━━━━━━━━━Persistent storage")]
    end

    %% FLOW %%
    CALLER1 --> FAC
    FAC --> SCOPE
    SCOPE --> REPO1
    BASE --> REPO1
    REPO1 --> ADAPTER
    ADAPTER --> DB

    %% CLASS ASSIGNMENTS %%
    class CALLER1 cli;
    class FAC,SCOPE phase;
    class REPO1 newComponent;
    class BASE stateNode;
    class ADAPTER handler;
    class DB integration;

Color Legend: | Color | Category | Description | |-------|----------|-------------| | Dark Blue | Callers | Services/handlers that use repositories | | Purple | Factory | Repository construction and scoping | | Green | Repositories | Repository implementations | | Teal | Base | Generic base repository | | Orange | Conversion | Format adapters/DTOs | | Red | Storage | Database tables/collections |

Repository Categories

| Category | Count | Key Repositories | |----------|-------|------------------| | {category} | {N} | {list} |

Key Query Patterns

| Pattern | Repository Method | Use Case | |---------|------------------|----------| | {pattern} | {method} | {use case} |

Entity Relationships

| Parent | Child | Cardinality | FK | |--------|-------|-------------|-----| | {parent} | {child} | {1:N/1:1} | {fk field} |

---

## Pre-Diagram Checklist

Before creating the diagram, verify:

- [ ] LOADED `/autoskillit:mermaid` skill using the Skill tool
- [ ] Using ONLY classDef styles from the mermaid skill (no invented colors)
- [ ] Diagram will include a color legend table

---

## Related Skills

- `/autoskillit:make-arch-diag` - Parent skill for lens selection
- `/autoskillit:mermaid` - MUST BE LOADED before creating diagram
- `/autoskillit:arch-lens-data-lineage` - For data flow view
- `/autoskillit:arch-lens-c4-container` - For storage container view

## Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

- **Author:** [TalonT-Org](https://github.com/TalonT-Org)
- **Source:** [TalonT-Org/AutoSkillit](https://github.com/TalonT-Org/AutoSkillit)
- **License:** MIT

Install and usage instructions live in the source repository linked above.