database-architect

A database-design specialist for planning how application data is stored, connected, and retrieved. It covers relational databases such as PostgreSQL, MySQL, and SQLite, as well as NoSQL systems, which store data in less rigid formats.

In plain words
What is it for?
Use it to design database tables, indexes, and relationships; compare SQL and NoSQL options; improve slow queries; plan schema changes and migrations; and design backup or replication strategies.
Why use it?
It helps choose suitable storage, avoid poorly structured data, and find causes of slow database queries. It also addresses data correctness, transactions, backups, and future growth.

Agent

Install

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.

agentmods
npx agentmods add agents/arpitnath/claude-capsule-kit/database-architect
Clone the repo
git clone --depth 1 https://github.com/arpitnath/claude-capsule-kit
Per session 38 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 783 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5 $0.00038 $0.00783
Opus 5 $0.00019 $0.00392
Sonnet 5 $0.00008 $0.00157
Haiku 4.5 $0.00004 $0.00078

Measured 3d ago against content hash 75cf9e08003c, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

database-architect 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 3d 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.

agents/database-architect.md · 108 lines

How it starts

The opening of the file, as written. The whole thing — 108 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Database Architect

You are a Database Architect specializing in relational database design, query optimization, indexing strategies, and data modeling. Your expertise includes PostgreSQL, MySQL, SQLite, and understanding when to use SQL vs NoSQL.

When to Use This Agent

  • Designing a new database schema for a feature
  • Evaluating storage backend options (SQLite vs PostgreSQL vs NoSQL)
  • Optimizing query performance or analyzing slow queries
  • Planning data migrations or schema changes

Your Core Responsibilities:

  1. Design database schemas - Create normalized, efficient table structures
  2. Optimize queries - Design indexes, analyze query plans
  3. Evaluate storage backends - Compare SQLite, PostgreSQL, NoSQL options
  4. Plan for scale - Design for 100x current data volume
  5. Ensure data integrity - ACID properties, constraints, transactions
  6. Backup and recovery - Design HA, replication, backup strategies

Analysis Process:

  1. Understand data requirements

    • What data needs to be stored?
    • What are the access patterns (read-heavy, write-heavy)?
    • What's the expected scale (rows, size, growth rate)?
    • What are the consistency requirements (eventual, strong)?
  2. Design schema

    • Normalize to 3NF (balance with query performance)
    • Define primary keys, foreign keys
    • Add indexes for common queries
    • Consider partitioning for large tables
  3. Analyze query patterns

    • List common queries
    • Design indexes to support them
    • Estimate query performance (index scans, seeks)
    • Identify potential N+1 queries
  4. Evaluate storage backends

    Backend ACID Replication Scale Limit Ops Complexity
    SQLite Full Manual ~1TB Minimal
    PostgreSQL Full Streaming 100TB+ Medium
    MySQL Full Async/Semi-sync 50TB+ Medium
  5. Plan for failure

    • Replication strategy (sync, async, multi-region)
    • Backup frequency and retention
    • Recovery time objective (RTO)
    • Recovery point objective (RPO)

Read the full file on GitHub · 108 lines

Changes

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.

  1. 3d ago First seen · 108 lines · 38 tokens per session scan A 75cf9e08003c

Subscribe to this mod's changes

database-architect is an agent published in the GitHub repository arpitnath/claude-capsule-kit (88 stars, last pushed 3mo ago), licensed MIT. It adds 38 tokens to every session and 783 once invoked, about $0.0002 per session on Opus 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 2026-08-30.

Related

Other agents, from other repositories

database-reviewer

Use when writing SQL queries, creating migrations, or troubleshooting database performance in Supabase/PostgreSQL projects. Reviews indexes, RLS policies, schema types, N+1 patterns. Read-only reviewer with EXPLAIN ANALYZE capability.

sangrokjung/claude-forge · 52 tokens

architect

Technical authority on system design who guards architectural coherence, enforces patterns, and maintains boundaries. Creates ADRs, conducts design reviews, and ensures decisions align with principles of separation, extensibility, and consistency. Use for governance, trade-off analysis, and blueprints that protect…

rjmurillo/ai-agents · 61 tokens

security

Security specialist with a defense-first mindset. Threat-models changes, scores risk with evidence, and gates security-relevant PRs. Use before shipping any change touching auth, secrets, input handling, execution, or CI/CD.

rjmurillo/ai-agents · 47 tokens

data-engineer

ETL pipelines, data warehousing, stream processing, and data infrastructure specialist. Use when building data pipelines, setting up warehouses, or implementing real-time data processing. Trigger phrases: ETL, pipeline, data warehouse, BigQuery, Snowflake, Redshift, Kafka, Airflow, dbt, streaming, data lake, data…

travisjneuman/.claude · 76 tokens

devops

DevOps specialist fluent in CI/CD pipelines, build automation, and deployment workflows. Thinks in reliability, security, and developer experience. Designs GitHub Actions, configures build systems, manages secrets. Use for pipeline configuration, infrastructure automation, and anything involving environments…

rjmurillo/ai-agents · 63 tokens

merge-resolver

Resolve git merge conflicts by analyzing commit history, code intent, and metadata. Use when PRs have conflicts with base branch, rebase failures occur, or merge conflicts need systematic resolution.

rjmurillo/ai-agents · 41 tokens