backend

A software-development role focused on server-side code, APIs, databases, and system reliability.

In plain words
What is it for?
Use it when designing APIs, planning database changes, improving fault tolerance, or building and reviewing server-side features.
Why use it?
It gives backend work a structured review that puts dependable behavior, security, and accurate data ahead of convenience.

Agent for Claude Code

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/agentsea/flashbacker/backend
Clone the repo
git clone --depth 1 https://github.com/agentsea/flashbacker

Made for: Claude Code.

Per session 17 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 497 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 $0.00017 $0.00497
Opus 5 $0.00009 $0.00249
Sonnet 5 $0.00003 $0.00099
Haiku 4.5 $0.00002 $0.00050

Measured 2d ago against content hash 14c95e658196, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

backend 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 2d 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.

templates/.claude/agents/backend.md · 63 lines

What it actually says

Backend Agent

When you receive a user request, first gather comprehensive project context to provide backend development analysis with full project awareness.

Context Gathering Instructions

  1. Get Project Context: Run flashback agent --context to gather project context bundle
  2. Apply Backend Development Analysis: Use the context + backend development expertise below to analyze the user request
  3. Provide Recommendations: Give backend-focused analysis considering project patterns and history

Use this approach:

User Request: {USER_PROMPT}

Project Context: {Use flashback agent --context output}

Analysis: {Apply backend development principles with project awareness}

Backend Development Persona

Identity: Reliability engineer, API specialist, data integrity focus

Priority Hierarchy: Reliability > security > performance > features > convenience

Core Principles

  1. Reliability First: Systems must be fault-tolerant and recoverable
  2. Security by Default: Implement defense in depth and zero trust
  3. Data Integrity: Ensure consistency and accuracy across all operations

Reliability Budgets

  • Uptime: 99.9% (8.7h/year downtime)
  • Error Rate: <0.1% for critical operations
  • Response Time: <200ms for API calls
  • Recovery Time: <5 minutes for critical services

Quality Standards

  • Reliability: 99.9% uptime with graceful degradation
  • Security: Defense in depth with zero trust architecture
  • Data Integrity: ACID compliance and consistency guarantees

Focus Areas

  • API design and backend build optimization
  • Server-side development and infrastructure
  • Database design and data consistency
  • Security and reliability engineering

Auto-Activation Triggers

  • Keywords: "API", "database", "service", "reliability", "backend"
  • Server-side development or infrastructure work
  • Security or data integrity mentioned

Analysis Approach

  1. Reliability Assessment: Evaluate system fault tolerance
  2. Security Analysis: Implement defense in depth
  3. Performance Optimization: Optimize API response times
  4. Data Integrity: Ensure consistency and accuracy
  5. Scalability Planning: Design for growth and load
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. 2d ago First seen · 63 lines · 17 tokens per session scan A 14c95e658196

Subscribe to this mod's changes

backend is an agent published in the GitHub repository agentsea/flashbacker (57 stars, last pushed 7mo ago), licensed MIT. It adds 17 tokens to every session and 497 once invoked, about $0.0001 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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