Unable to use gemma model

[sahilrajput03]

Unable to use gemma model:

import { FunctionTool, LlmAgent } from '@google/adk';
import { z } from 'zod';

/* Mock tool implementation */
const getCurrentTime = new FunctionTool({
    name: 'get_current_time',
    description: 'Returns the current time in a specified city.',
    parameters: z.object({
        city: z.string().describe("The name of the city for which to retrieve the current time."),
    }),
    execute: ({ city }) => {
        return { status: 'success', report: `The current time in ${city} is 10:30 AM` };
    },
});

export const rootAgent = new LlmAgent({
    name: 'hello_time_agent',
    model: 'gemma-4-31b-it',
    description: 'Tells the current time in a specified city.',
    instruction: `You are a helpful assistant that tells the current time in a city.
                Use the 'getCurrentTime' tool for this purpose.`,
    tools: [getCurrentTime],
});

Output:

 npx adk run agent.ts
[dotenv@17.3.1] injecting env (1) from .env -- tip: ⚙️  write to custom object with { processEnv: myObject }
(node:47611) [DEP0040] DeprecationWarning: The `punycode` module is deprecated. Please use a userland alternative instead.
(Use `node --trace-deprecation ...` to show where the warning was created)
Running agent hello_time_agent, type exit to exit.
[user]: hi
[ADK INFO]: event:  {"invocationId":"e-b42c2088-d807-42ba-9d4e-64c8e81aa096","author":"user","actions":{"stateDelta":{},"artifactDelta":{},"requestedAuthConfigs":{},"requestedToolConfirmations":{}},"content":{"role":"user","parts":[{"text":"hi"}]},"id":"Ae63mZ14","longRunningToolIds":[],"timestamp":1780861449099}
Error: Model gemma-4-31b-it not found.
    at Od.resolve (/private/var/folders/5k/slsrk9d90bg806p4zvyx829m0000gn/T/adk_agent_loader/1780861447507/agent.cjs:256:6857)
    at Od.newLlm (/private/var/folders/5k/slsrk9d90bg806p4zvyx829m0000gn/T/adk_agent_loader/1780861447507/agent.cjs:256:6367)
    at get canonicalModel (/private/var/folders/5k/slsrk9d90bg806p4zvyx829m0000gn/T/adk_agent_loader/1780861447507/agent.cjs:323:2389)
    at trr.runAsync (/private/var/folders/5k/slsrk9d90bg806p4zvyx829m0000gn/T/adk_agent_loader/1780861447507/agent.cjs:256:16297)
    at runAsync.next (<anonymous>)
    at TA.runOneStepAsync (/private/var/folders/5k/slsrk9d90bg806p4zvyx829m0000gn/T/adk_agent_loader/1780861447507/agent.cjs:323:4802)
    at runOneStepAsync.next (<anonymous>)
    at TA.runAsyncImpl (/private/var/folders/5k/slsrk9d90bg806p4zvyx829m0000gn/T/adk_agent_loader/1780861447507/agent.cjs:323:4282)
    at runAsyncImpl.next (<anonymous>)
    at TA.<anonymous> (/private/var/folders/5k/slsrk9d90bg806p4zvyx829m0000gn/T/adk_agent_loader/1780861447507/agent.cjs:246:39665)

[kalenkevich]

@sahilrajput03 Hello, try this one:

import { FunctionTool, LlmAgent, Gemini } from '@google/adk';
import { z } from 'zod';

/* Mock tool implementation */
const getCurrentTime = new FunctionTool({
    name: 'get_current_time',
    description: 'Returns the current time in a specified city.',
    parameters: z.object({
        city: z.string().describe("The name of the city for which to retrieve the current time."),
    }),
    execute: ({ city }) => {
        return { status: 'success', report: `The current time in ${city} is 10:30 AM` };
    },
});

export const rootAgent = new LlmAgent({
    name: 'hello_time_agent',
    model: new Gemini({ model: 'gemma-4-31b-it' }),
    description: 'Tells the current time in a specified city.',
    instruction: `You are a helpful assistant that tells the current time in a city.
                Use the 'getCurrentTime' tool for this purpose.`,
    tools: [getCurrentTime],
});

model: new Gemini({ model: 'gemma-4-31b-it' }) instead of model: 'gemma-4-31b-it'