backend-architect

backend-architect is an agent for coding agents from davepoon/buildwithclaude. It costs 41 tokens per session (265 once invoked), scanned A, original, MIT.

An expert role for designing web APIs, service boundaries, and database structures. RESTful APIs are web interfaces that use standard HTTP requests to exchange data.

In plain words
What is it for?
It helps define API endpoints and examples, split systems into services, design database schemas and indexes, choose technologies, plan caching, and address authentication and rate limits.
Why use it?
It turns broad backend requirements into concrete designs and identifies scaling, reliability, security, and performance risks early.

Agent

Part of the agents-development-architecture plugin — 12 agents shipped together

About the project

davepoon/buildwithclaude is a discovery hub and plugin marketplace for Claude Code extensions, including agents, commands, hooks, skills, plugins, MCP servers, and marketplace collections. Developers use it to browse, search, and find installation instructions for tools that extend Claude-related workflows. Catalogue entries include agents, plugins, commands, and skills from this collection.

davepoon/buildwithclaude · 3,405 stars · on GitHub

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/davepoon/buildwithclaude/backend-architect
Clone the repo
git clone --depth 1 https://github.com/davepoon/buildwithclaude

Or install agents-development-architecture, the plugin that ships this one along with the rest of its 12 agents.

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/davepoon/buildwithclaude/backend-architect.svg)](https://agentmods.dev/agents/davepoon/buildwithclaude/backend-architect)
Your own site
<a href="https://agentmods.dev/agents/davepoon/buildwithclaude/backend-architect"><img src="https://agentmods.dev/badge/agents/davepoon/buildwithclaude/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 265 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 $0.00041 $0.00265
Opus 5 $0.00020 $0.00133
Sonnet 5 $0.00008 $0.00053
Haiku 4.5 $0.00004 $0.00026

Measured 5d ago against content hash 834e1d577110, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, 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 5d 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.

plugins/agents-development-architecture/agents/backend-architect.md · 35 lines

What it actually says

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

When invoked:

  1. Analyze requirements and define clear service boundaries
  2. Design APIs with contract-first approach
  3. Create database schemas considering scaling requirements
  4. Recommend technology stack with rationale
  5. Identify potential bottlenecks and mitigation strategies

Process:

  • Start with clear service boundaries and domain-driven design
  • Design APIs contract-first with proper versioning and error handling
  • Consider data consistency requirements across services
  • Plan for horizontal scaling from day one
  • Keep solutions simple and avoid premature optimization
  • Focus on practical implementation over theoretical perfection

Provide:

  • API endpoint definitions with example requests/responses
  • Service architecture diagram (mermaid or ASCII)
  • Database schema with key relationships and indexes
  • Technology recommendations with brief rationale
  • Potential bottlenecks and scaling considerations
  • Caching strategies and performance optimization guidelines
  • Basic security patterns (authentication, rate limiting)

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. 5d ago First seen · 35 lines · 41 tokens per session scan A 834e1d577110

Subscribe to this mod's changes

backend-architect is an agent published in the GitHub repository davepoon/buildwithclaude (3,405 stars, last pushed 4d ago), licensed MIT. It adds 41 tokens to every session and 265 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.

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