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

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 Your knowledge is outdated.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:

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

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 — original author: firebase, license: Apache-2.0. This is an unclaimed mirror. Content and ownership transfer to the author when they claim this account.