contract-test

contract-test is a skill for Claude Code, Codex from flurdy/agent-skills. It costs 39 tokens per session (3,116 once invoked), scanned A, original, MIT.

A command for consumer-driven contract tests, which check that services agree on an API's requests and responses. It stores contracts as JSON files and shares them through the filesystem instead of a central broker.

In plain words
What is it for?
Use it after changing an API client, connector, endpoint, or data model, or to generate, sync, and verify contracts across one or more services.
Why use it?
It catches mismatches between a service that calls an API and the service that provides it before those changes break integration.

Skill for Claude CodeCodex

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 skills/flurdy/agent-skills/contract-test
Any agent
npx skills add flurdy/agent-skills --skill contract-test
Clone the repo
git clone --depth 1 https://github.com/flurdy/agent-skills

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 contract-test

README.md
[![agentmods](https://agentmods.dev/badge/skills/flurdy/agent-skills/contract-test.svg)](https://agentmods.dev/skills/flurdy/agent-skills/contract-test)
Your own site
<a href="https://agentmods.dev/skills/flurdy/agent-skills/contract-test"><img src="https://agentmods.dev/badge/skills/flurdy/agent-skills/contract-test.svg" alt="Measured on agentmods" height="20"></a>
Per session 39 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,116 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 $0.00039 $0.03116
Opus 5 $0.00019 $0.01558
Sonnet 5 $0.00008 $0.00623
Haiku 4.5 $0.00004 $0.00312

Measured 4d ago against content hash bb8e02bdba46, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

contract-test 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 4d 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/contract-test/SKILL.md · 342 lines

How it starts

The opening of the file, as written. The whole thing — 342 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Contract Test (Pact-Lite)

Consumer-driven contract testing without a broker. Contracts are JSON files exchanged directly between consumer and provider services via the filesystem.

When to Use

  • After modifying a connector, API client, or endpoint interface (request/response models, URLs, headers)
  • When adding a new REST endpoint that other services will consume
  • To verify contracts haven't broken after upstream/downstream changes
  • When a consumer or provider test is failing and you need to re-sync contracts
  • After bulk changes that touch multiple services — run project-wide to verify all contracts

Usage

/contract-test                     # Auto-detect: run contract tests for current service
/contract-test consumer            # Run consumer tests to generate contract files
/contract-test sync                # Copy generated contracts to provider services
/contract-test provider            # Run provider verification against current contracts
/contract-test full                # Single-service: consumer + sync + provider for current service
/contract-test full all            # Multi-service: ALL consumers → sync → normalize → ALL providers
/contract-test full <svc> <svc>    # Multi-service: named consumers → sync → normalize → affected providers
/contract-test status              # Show contract test coverage and staleness

Concepts

Consumer-Driven Contracts (Pact-Lite)

This is a lightweight version of the Pact workflow that works without a broker:

  1. Consumer services define expected interactions with providers in test code
  2. Consumer tests generate contract files (JSON) describing those expectations
  3. Contract files are copied from consumer to provider (no broker — just filesystem)
  4. Provider services verify they satisfy all consumer contracts

Roles

  • Consumer: A service that calls another service's API. Generates .json contract files.
  • Provider: A service that exposes an API. Verifies contracts from its consumers.
  • A service can be both consumer and provider for different dependencies.

Read the full file on GitHub · 342 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. 4d ago First seen · 342 lines · 39 tokens per session scan A bb8e02bdba46

Subscribe to this mod's changes

contract-test is a skill published in the GitHub repository flurdy/agent-skills (7 stars, last pushed 6d ago), licensed MIT. It adds 39 tokens to every session and 3,116 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 2026-08-31.

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