⚡ Record AI responses. Replay instantly.

AIMock — the AI fixture library
for developers who ship fast

Record real OpenAI, Anthropic, Google, and Tavily responses once. Replay them instantly in every test run — no tokens, no latency, no flaky CI. Some call it AIFixture. Some call it ReplayAI. Developers call it their secret weapon.

Get Free API Key See how it works
POST /api/aimock/replay
# Replay a recorded OpenAI fixture — instant, zero cost
curl -X POST https://api.getbrains4ai.com/api/aimock/replay \
  -H "X-AIMock-Key: amk_your_key_here" \
  -H "Content-Type: application/json" \
  -d '{
    "provider": "openai",
    "request": {
      "model": "gpt-4o",
      "messages": [{"role": "user", "content": "Summarize this contract"}]
    }
  }'

# Response: exact fixture match, <5ms
{
  "ok": true,
  "fixture": { "response_payload": { ... }, "latency_ms": 312 },
  "_meta": { "calls_this_month": 1, "monthly_limit": 1000 }
}
4
AI providers supported
<5ms
Fixture replay latency
1,000
Free replays per month
0
Tokens consumed on replay
How it works

Record once. Replay forever.

Three steps. Your tests run in milliseconds instead of seconds, with zero API spend.

1

Record a real call

Make one real call to OpenAI, Anthropic, or another provider via the admin API. AIMock stores the full response as a fixture keyed to the request shape.

2

Replay in your tests

In CI/CD or local dev, swap your real API calls for POST /api/aimock/replay. Get the exact same response in <5ms without any provider credentials.

3

Detect drift automatically

When provider APIs change, AIMock's drift detector compares live vs. stored responses and alerts you before your production code breaks.

4

Inject failure scenarios

Simulate timeouts, rate limits, auth failures, and malformed responses to verify your retry logic handles real-world edge cases correctly.

Supported Providers

Every major AI provider, covered.

All four providers in Storm's active AI stack — fixtures work across all models within each provider.

OpenAI (GPT-4o, GPT-4 Turbo, GPT-3.5)
Anthropic (Claude 3.5 Sonnet, Haiku)
Google (Gemini 2.0 Flash, 1.5 Pro)
Tavily (Search API, basic + advanced)
API Reference

Simple endpoints. No SDK required.

Base URL: https://api.getbrains4ai.com/api/aimock

GET
/providers
List all registered AI providers and their supported models.
Public — no key needed
GET
/pricing
Return current tier limits and feature matrix as JSON.
Public — no key needed
POST
/replay
Retrieve a stored fixture matching the provider + request shape. Increments your monthly counter.
X-AIMock-Key required
GET
/usage
Check your key's total calls, monthly usage, and plan limits.
X-AIMock-Key required

Start free. Scale when you need to.

Free tier covers most solo developers and small teams. Contact us for a Pro key.

Free
$0 / month
Everything you need to get started.
  • 1,000 fixture replays / month
  • 4 AI providers (OpenAI, Anthropic, Google, Tavily)
  • Usage dashboard via API
  • JSON fixture export
  • No credit card required
Request Free Key