frontend-backend-contract

frontend-backend-contract is a skill for Claude Code, Codex from aetox-skills/Aetox-Agents-Team. It costs 62 tokens per session (2,394 once invoked), scanned A, original, no licence file.

A set of rules for making frontend and backend agents agree on an API—the connection through which a user interface exchanges data with a server—before they build or change it.

In plain words
What is it for?
Use it when creating API endpoints, sharing data types, handling errors, or connecting frontend and backend behavior.
Why use it?
It prevents one side from guessing how the other side works, reducing mismatched data, unclear errors, and broken integrations.

Skill for Claude CodeCodex

Which agent this was written for is unclear — body not stored (licence); the path alone says nothing.

Good fit Use it when creating API endpoints, sharing data types, handling errors, or connecting frontend and backend behavior.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/aetox-skills/aetox-agents-team/frontend-backend-contract
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.

Any agent
npx skills add aetox-skills/Aetox-Agents-Team --skill frontend-backend-contract
Clone the repo
git clone --depth 1 https://github.com/aetox-skills/Aetox-Agents-Team

Made for: Claude Code, Codex.

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 frontend-backend-contract

README.md
[![agentmods](https://agentmods.dev/badge/skills/aetox-skills/aetox-agents-team/frontend-backend-contract/github.svg)](https://agentmods.dev/skills/aetox-skills/aetox-agents-team/frontend-backend-contract)
Your own site
<a href="https://agentmods.dev/skills/aetox-skills/aetox-agents-team/frontend-backend-contract"><img src="https://agentmods.dev/badge/skills/aetox-skills/aetox-agents-team/frontend-backend-contract/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.

agentmods 80×15 button for frontend-backend-contract

Your own site · 80×15
<a href="https://agentmods.dev/skills/aetox-skills/aetox-agents-team/frontend-backend-contract"><img src="https://agentmods.dev/badge/skills/aetox-skills/aetox-agents-team/frontend-backend-contract.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 62 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,394 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 unknown 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 $0.00062 $0.02394
Opus 5 $0.00031 $0.01197
Sonnet 5 $0.00012 $0.00479
Haiku 4.5 $0.00006 $0.00239

Measured 11d ago against content hash a5dc762438ed, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

frontend-backend-contract 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 11d 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.

skills/frontend-backend-contract/SKILL.md · 299 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

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. 11d ago First seen · 299 lines · 62 tokens per session scan A a5dc762438ed

Subscribe to this mod's changes

frontend-backend-contract is a skill published in the GitHub repository aetox-skills/Aetox-Agents-Team (2 stars, last pushed 2mo ago), with no licence file. It adds 62 tokens to every session and 2,394 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 2026-08-31.

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