What is emulate-seed?

A workflow for creating configuration files for stateful API emulation. API emulation provides a local test version of services such as GitHub, Stripe, OAuth, or MongoDB Atlas, including changing state and related side effects.

Use it to configure local service emulators, prepare integration-test environments, set up CI tests, model webhooks and signatures, and isolate parallel test workers.

It lets developers test integrations and CI pipelines without relying on live services or simplistic fixed responses. Stateful behavior can reveal problems that basic mocks hide.

emulate-seed — Skill for Claude Code by yonatangross

Install

Getting it into your agent

It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.

Clone the repo

git clone --depth 1 https://github.com/yonatangross/orchestkit

agentmods

npx agentmods add skills/yonatangross/orchestkit/emulate-seed

Made for: Claude Code.

Or install ork, the plugin that ships this one along with the rest of its 106 skills, 35 commands, 36 agents, 32 hooks.

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.

README.md

[![agentmods](https://agentmods.dev/badge/skills/yonatangross/orchestkit/emulate-seed.svg)](https://agentmods.dev/skills/yonatangross/orchestkit/emulate-seed)

Your own site

<a href="https://agentmods.dev/skills/yonatangross/orchestkit/emulate-seed"><img src="https://agentmods.dev/badge/skills/yonatangross/orchestkit/emulate-seed.svg" alt="Measured on agentmods" height="20"></a>

Per session 86 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 4,679 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.

Model	Per session	Once invoked
Fable 5.1	$0.00086	$0.04679
Opus 5	$0.00043	$0.02339
Sonnet 5	$0.00017	$0.00936
Haiku 4.5	$0.00009	$0.00468

Measured 3d ago against content hash a349205bca51, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

emulate-seed 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 3d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/auto-discover.sh), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

plugins/ork/skills/emulate-seed/SKILL.md · 375 lines

How it starts

The opening of the file, as written. The whole thing — 375 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Emulate Seed Configs

Generate and manage seed configs for emulate (Apache-2.0) — Vercel Labs' stateful API emulation tool. Each category has individual rule files in rules/ loaded on-demand.

Paired agent: This skill pairs with the emulate-engineer subagent (subagent_type: "ork:emulate-engineer"). When a task involves generating a full emulate config from scratch, webhook HMAC setup, CI pipeline integration, or parallel-worker port isolation, spawn the agent rather than handling it inline — it has the full 13-emulator service-port matrix and seed-rules in context.

Not mocks. Emulate provides full state machines with cascading deletes, cursor pagination, webhook delivery, and HMAC signature verification. Create a PR via the API and it appears in GET /repos/:owner/:repo/pulls. Delete a repo and its issues, PRs, and webhooks cascade-delete.

New in 2026-04 (emulate 0.4.x)

Modular @emulators/* packages — each service is its own package (@emulators/github, @emulators/stripe, etc.); top-level emulate re-exports createEmulator and the CLI.
4 new services (12 total): mongoatlas:4007, okta:4008, resend:4009, stripe:4010 with drop-in seed YAML blocks.
Resend local inbox — GET http://localhost:4009/inbox returns captured emails for assertions without hitting a real provider.
Stripe hosted checkout — real session redirect flow + checkout.session.completed/expired webhook delivery, suitable for E2E payment tests.
MongoDB Atlas — Admin API v2 (projects/clusters/DB users) + Data API v1 with full CRUD + aggregate.
Okta OIDC — full discovery, JWKS, authorize/token/userinfo/revoke/introspect plus Users/Groups/Apps CRUD.
Entra / Apple / Slack expansions (v0.4.0) — PKCE + refresh rotation (Entra), RS256 JWKS (Apple), OAuth v2 consent UI (Slack).
@emulators/adapter-next — catch-all Next.js route handler runs emulators on the same origin as the app; fixes OAuth callback URL drift on Vercel preview deploys.

Read the full file on GitHub · 375 lines

Files

What ships with it

17 files 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.

3d ago First seen · 375 lines · 86 tokens per session scan A a349205bca51

Subscribe to this mod's changes

emulate-seed is a skill published in the GitHub repository yonatangross/orchestkit (229 stars, last pushed today), licensed MIT. It adds 86 tokens to every session and 4,679 once invoked, about $0.0004 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 2026-09-03.

Backend and APIs E2E testing MongoDB Testing api emulation clerk emulate github google okta resend seed stripe vercel

api-tester

A tool for creating and checking API tests from the real API contract and implementation. An API is the agreed way that software sends requests and receives responses.

laolaoshiren/claude-code-skills-zh · 86 tokens

backend/testing-guide

A guide for writing backend tests: small unit tests, tests that check connected parts such as an API and database, and end-to-end tests that follow a complete user flow.

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endpoint-probe

Probes each major Agent Monitor API route — /api/stats, /api/analytics, /api/sessions, /api/pricing/cost, /api/workflows/runs, /api/cc-config/overview — and reports each one's HTTP status, latency, and response shape, flagging which are reachable. Use to verify a dashboard install is wired up correctly.

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emulate-seed