api-contract-architecture

api-contract-architecture is a skill for Claude Code, Codex from devcodex-labs/devcodex. It costs 67 tokens per session (1,696 once invoked), scanned A, original, AGPL-3.0.

An architecture guide for public APIs, including HTTP services, software-development kits, command-line tools, schemas, types, errors, pagination, filtering, and compatibility.

In plain words
What is it for?
Use it to design or review API contracts, version changes, error models, idempotency, migrations, consumer impact, and validation rules.
Why use it?
It helps teams agree on the user-facing contract before implementation, reducing breaking changes and confusion for software that depends on the API.

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 to design or review API contracts, version changes, error models, idempotency, migrations, consumer impact, and validation rules.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/devcodex-labs/devcodex/api-contract-architecture
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 devcodex-labs/devcodex --skill api-contract-architecture
Clone the repo
git clone --depth 1 https://github.com/devcodex-labs/devcodex

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 api-contract-architecture

README.md
[![agentmods](https://agentmods.dev/badge/skills/devcodex-labs/devcodex/api-contract-architecture/github.svg)](https://agentmods.dev/skills/devcodex-labs/devcodex/api-contract-architecture)
Your own site
<a href="https://agentmods.dev/skills/devcodex-labs/devcodex/api-contract-architecture"><img src="https://agentmods.dev/badge/skills/devcodex-labs/devcodex/api-contract-architecture/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 api-contract-architecture

Your own site · 80×15
<a href="https://agentmods.dev/skills/devcodex-labs/devcodex/api-contract-architecture"><img src="https://agentmods.dev/badge/skills/devcodex-labs/devcodex/api-contract-architecture.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 67 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,696 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 $0.00067 $0.01696
Opus 5.5 $0.00027 $0.00678
Sonnet 5.5 $0.00013 $0.00339
Haiku 4.5 $0.00007 $0.00170

Measured today against content hash ba20f4a8ce48, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

api-contract-architecture 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 today.

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.

content/skills/api-contract-architecture/SKILL.md · 88 lines

The source is not reproduced here

Licensed AGPL-3.0

The repository is licensed AGPL-3.0, which this catalogue does not treat as permission to reproduce the file. Read it at the source.

Read it on GitHub

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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. today Changed · +8 lines ba20f4a8ce48
  2. 1mo ago First seen · 80 lines · 67 tokens per session scan A aa38b2f7dc0f

Subscribe to this mod's changes

api-contract-architecture is a skill published in the GitHub repository devcodex-labs/devcodex (439 stars, last pushed yesterday), licensed AGPL-3.0. It adds 67 tokens to every session and 1,696 once invoked, about $0.0003 per session on Opus 5.5. 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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