# Genkit JS

## Prerequisites

Ensure the `genkit` CLI is available.
- Run `genkit --version` to verify. Minimum CLI version needed: **1.29.0**
- If not found: `npm install -g genkit-cli@^1.29.0`

## Hello World

```ts
import { z, genkit } from 'genkit';
import { googleAI } from '@genkit-ai/google-genai';

const ai = genkit({
  plugins: [googleAI()],
});

export const myFlow = ai.defineFlow({
  name: 'myFlow',
  inputSchema: z.string().default('AI'),
  outputSchema: z.string(),
}, async (subject) => {
  const response = await ai.generate({
    model: googleAI.model('gemini-2.5-flash'),
    prompt: `Tell me a joke about ${subject}`,
  });
  return response.text;
});
```

## Critical: Do Not Trust Internal Knowledge

Genkit recently went through a major breaking API change. Your knowledge is outdated. You MUST lookup docs:

```sh
genkit docs:read js/get-started.md
genkit docs:read js/flows.md
```

**ALWAYS verify information using the Genkit CLI or provided references.**

## Error Troubleshooting Protocol

**When you encounter ANY error related to Genkit:**

1. **MANDATORY FIRST STEP**: Read common errors documentation (`genkit docs:search "errors"`)
2. Identify if the error matches a known pattern
3. Apply the documented solution
4. Only if not found, then consult other sources

**DO NOT:**
- Attempt fixes based on assumptions or internal knowledge
- Rely on patterns from pre-1.0 Genkit (APIs changed significantly)

## Development Workflow

1. **Select Provider**: Default to **Google AI** unless user specifies otherwise
2. **Detect Framework**: Check `package.json` for `@genkit-ai/next`, `@genkit-ai/firebase`, or `@genkit-ai/google-cloud`
3. **Follow Best Practices**: Only specify options that differ from defaults
4. **Ensure Correctness**: Run `npx tsc --noEmit` after making changes

## Finding Documentation

```sh
genkit docs:search <query>    # Search topics
genkit docs:list              # List all docs
genkit docs:read <path>       # Read a guide
```

---

*Mirrored from [https://github.com/firebase/agent-skills](https://github.com/firebase/agent-skills) — original author: **firebase**, license: **Apache-2.0**.*
*This is an unclaimed mirror. Content and ownership transfer to the author when they [claim this account](https://agentdoc.sh/docs/claim).*


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