backend-architect

backend-architect is an agent for Claude Code from sonomirco/agents-and-commands. It costs 41 tokens per session (228 once invoked), scanned A, a copy of backend-architect, Apache-2.0.

A software-architecture guide for backend systems, the server-side parts that store data and provide APIs. It designs REST APIs, service boundaries, database schemas, caching, and basic security controls.

In plain words
What is it for?
Use it to plan a new backend service, define microservices, design database tables and indexes, specify API endpoints, or review performance and scalability risks.
Why use it?
It helps turn a broad backend idea into clear services, data relationships, and communication rules. It also highlights consistency requirements, likely bottlenecks, and scaling concerns before implementation.

Agent for Claude Code

Written for Claude Code: a Claude Code subagent (agents/*.md). Also seen: model in frontmatter.

Good fit Use it to plan a new backend service, define microservices, design database tables and indexes, specify API endpoints, or review performance and scalability risks.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/sonomirco/agents-and-commands/backend-architect
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.

Clone the repo
git clone --depth 1 https://github.com/sonomirco/agents-and-commands

Made for: Claude Code.

Wrote 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.

agentmods badge for backend-architect

README.md
[![agentmods](https://agentmods.dev/badge/agents/sonomirco/agents-and-commands/backend-architect.svg)](https://agentmods.dev/agents/sonomirco/agents-and-commands/backend-architect)
Your own site
<a href="https://agentmods.dev/agents/sonomirco/agents-and-commands/backend-architect"><img src="https://agentmods.dev/badge/agents/sonomirco/agents-and-commands/backend-architect.svg" alt="Measured on agentmods" height="20"></a>
Per session 41 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 228 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin 92% copy Near-identical to another mod 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 5.1 $0.00041 $0.00228
Opus 5 $0.00020 $0.00114
Sonnet 5 $0.00008 $0.00046
Haiku 4.5 $0.00004 $0.00023

Measured 8d ago against content hash fbd3a9f3aa33, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

backend-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 8d 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.

Origin

This is a copy

92% identical to backend-architect — 2 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

plugins/backend-architecture/agents/backend-architect.md · 31 lines

What it actually says

You are a backend system architect specializing in scalable API design and microservices.

Focus Areas

  • RESTful API design with proper versioning and error handling
  • Service boundary definition and inter-service communication
  • Database schema design (normalization, indexes, sharding)
  • Caching strategies and performance optimization
  • Basic security patterns (auth, rate limiting)

Approach

  1. Start with clear service boundaries
  2. Design APIs contract-first
  3. Consider data consistency requirements
  4. Plan for horizontal scaling from day one
  5. Keep it simple - avoid premature optimization

Output

  • API endpoint definitions with example requests/responses
  • Service architecture diagram (mermaid or ASCII)
  • Database schema with key relationships
  • List of technology recommendations with brief rationale
  • Potential bottlenecks and scaling considerations

Always provide concrete examples and focus on practical implementation over theory.

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. 8d ago First seen · 31 lines · 41 tokens per session scan A fbd3a9f3aa33

Subscribe to this mod's changes

backend-architect is an agent published in the GitHub repository sonomirco/agents-and-commands (12 stars, last pushed 6mo ago), licensed Apache-2.0. It adds 41 tokens to every session and 228 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 92% identical to backend-architect, differing in 2 lines, and is treated as a copy.