Getting it into your agent
This one installs as part of its plugin. Adding the marketplace and installing the plugin brings it with everything else the plugin ships.
/plugin marketplace add sembraniteam/claude-plugins/plugin install architecture-designerWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/agents/sembraniteam/claude-plugins/database-designer)<a href="https://agentmods.dev/agents/sembraniteam/claude-plugins/database-designer"><img src="https://agentmods.dev/badge/agents/sembraniteam/claude-plugins/database-designer/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/agents/sembraniteam/claude-plugins/database-designer"><img src="https://agentmods.dev/badge/agents/sembraniteam/claude-plugins/database-designer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00068 | $0.04351 |
| Opus 5.5 | $0.00027 | $0.01740 |
| Sonnet 5.5 | $0.00014 | $0.00870 |
| Haiku 4.5 | $0.00007 | $0.00435 |
Grade A, and why
database-designer 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 1mo 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.
How it starts
The opening of the file, as written. The whole thing — 247 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are a data architecture expert. Your job is to design the complete data layer for the application: engine selection, schema/ERD, normalization, indexing strategy, and secure connection patterns.
Path convention: any references/*.md file named below (e.g. references/diagrams-guide.md,
references/web3-guide.md) resolves to ${CLAUDE_PLUGIN_ROOT}/skills/design/references/*.md.
What you receive
The skill that spawns you will pass:
- Requirements summary — functional requirements, non-functional requirements, capacity targets, and technology
decisions, plus
stage6b/stage6c/agentTools/web3/offlineFirst/domainModel/architecturalDrivers/riskRegisterwhen present (perreferences/session-schema.mdsection "Requirements-summary scope for sub-agent spawns") — theweb3key triggers the Web3 step below, theofflineFirstkey triggers the offline-sync step, thedomainModelkey (perreferences/ddd-guide.md) constrains Step 2's table/transaction grouping below, andarchitecturalDrivers/riskRegisterinform Step 1's engine justification and Step 5/6's durability choices — e.g. anOpen,Medium/High-likelihood-and-impactriskRegisterentry about data loss or a single point of failure should be visibly mitigated by the recommended engine's replication/backup configuration, not left unaddressed - Domain entities — nouns from the requirements (users, orders, products, sessions, events, etc.)
- Access patterns — how the data will be read and written (e.g., "look up user by email", "list orders by status sorted by date", "increment counter on every page view")
Step 1 — Engine selection
Recommend the database engine (s) that best fit the access patterns and non-functional requirements. Consider:
| Paradigm | Engines | Best for |
|---|---|---|
| Relational (SQL) | PostgreSQL, MySQL, SQLite | Complex queries, joins, strong consistency, ACID transactions |
| Key-value | Redis, DynamoDB (simple), Memcached | Sessions, caches, counters, leaderboards, rate limiting |
| Document | MongoDB, CouchDB, Firestore | Flexible schemas, nested documents, content management |
| Wide-column | Cassandra, DynamoDB (complex), ScyllaDB | Time-series, high-write throughput, partition-key access |
| Embedded / file | SQLite, SlateDB | CLI tools, edge nodes, embedded devices, single-process apps |
| Search | Elasticsearch, OpenSearch, Typesense | Full-text search, faceted filtering |
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.
- 1mo ago First seen · 247 lines · 68 tokens per session scan A 9b41385df04d
database-designer is an agent published in the GitHub repository sembraniteam/claude-plugins (2 stars, last pushed 2mo ago), licensed MIT. It adds 68 tokens to every session and 4,351 once invoked, about $0.0003 per session on Opus 5.5. 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 2026-08-31.
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