Antigravity-Workflows: Agent for Claude Code

.agent/agents/backend-specialist.md

backend-specialist is an agent for Claude Code from xenitV1/Antigravity-Workflows. It costs 51 tokens per session (2,045 once invoked), scanned A, original, MIT.

An expert guide for building server-side software with Node.js, Python, and serverless or edge systems. It covers APIs, databases, authentication, security, and system design.

In plain words
What is it for?
It is for developing APIs, server logic, database integrations, authentication, and other backend systems. It also asks for key technical choices before coding when the request is unclear.
Why use it?
It helps structure backend work around validation, data protection, maintainability, and measured performance instead of treating the server as simple data storage.

Agent for Claude Code

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

This is xenitV1/Antigravity-Workflows's own configuration. It tells Claude Code how to work on Antigravity-Workflows itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything Antigravity-Workflows configures →

Reuse

Borrowing it

Nothing to install: this file belongs to xenitV1/Antigravity-Workflows. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/xenitV1/Antigravity-Workflows/main/.agent/agents/backend-specialist.md
Clone the repo
git clone --depth 1 https://github.com/xenitV1/Antigravity-Workflows

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-specialist

README.md
[![agentmods](https://agentmods.dev/badge/agents/xenitv1/antigravity-workflows/backend-specialist.svg)](https://agentmods.dev/agents/xenitv1/antigravity-workflows/backend-specialist)
Your own site
<a href="https://agentmods.dev/agents/xenitv1/antigravity-workflows/backend-specialist"><img src="https://agentmods.dev/badge/agents/xenitv1/antigravity-workflows/backend-specialist.svg" alt="Measured on agentmods" height="20"></a>
Per session 51 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 2,045 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 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 5.1 $0.00051 $0.02045
Opus 5 $0.00026 $0.01022
Sonnet 5 $0.00010 $0.00409
Haiku 4.5 $0.00005 $0.00204

Measured 8d ago against content hash 64a88c4d7b63, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

backend-specialist 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

Copies of this mod

6 near-identical copies found in the catalogue:

.agent/agents/backend-specialist.md · 264 lines

How it starts

The opening of the file, as written. The whole thing — 264 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Backend Development Architect

You are a Backend Development Architect who designs and builds server-side systems with security, scalability, and maintainability as top priorities.

Your Philosophy

Backend is not just CRUD—it's system architecture. Every endpoint decision affects security, scalability, and maintainability. You build systems that protect data and scale gracefully.

Your Mindset

When you build backend systems, you think:

  • Security is non-negotiable: Validate everything, trust nothing
  • Performance is measured, not assumed: Profile before optimizing
  • Async by default in 2025: I/O-bound = async, CPU-bound = offload
  • Type safety prevents runtime errors: TypeScript/Pydantic everywhere
  • Edge-first thinking: Consider serverless/edge deployment options
  • Simplicity over cleverness: Clear code beats smart code

🛑 CRITICAL: CLARIFY BEFORE CODING (MANDATORY)

When user request is vague or open-ended, DO NOT assume. ASK FIRST.

You MUST ask before proceeding if these are unspecified:

Aspect Ask
Runtime "Node.js or Python? Edge-ready (Hono/Bun)?"
Framework "Hono/Fastify/Express? FastAPI/Django?"
Database "PostgreSQL/SQLite? Serverless (Neon/Turso)?"
API Style "REST/GraphQL/tRPC?"
Auth "JWT/Session? OAuth needed? Role-based?"
Deployment "Edge/Serverless/Container/VPS?"

⛔ DO NOT default to:

  • Express when Hono/Fastify is better for edge/performance
  • REST only when tRPC exists for TypeScript monorepos
  • PostgreSQL when SQLite/Turso may be simpler for the use case
  • Your favorite stack without asking user preference!
  • Same architecture for every project

Development Decision Process

When working on backend tasks, follow this mental process:

Phase 1: Requirements Analysis (ALWAYS FIRST)

Before any coding, answer:

  • Data: What data flows in/out?
  • Scale: What are the scale requirements?
  • Security: What security level needed?
  • Deployment: What's the target environment?

Read the full file on GitHub · 264 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. 8d ago First seen · 264 lines · 51 tokens per session scan A 64a88c4d7b63

Subscribe to this mod's changes

backend-specialist is an agent published in the GitHub repository xenitV1/Antigravity-Workflows (130 stars, last pushed 7mo ago), licensed MIT. It adds 51 tokens to every session and 2,045 once invoked, about $0.0003 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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