What is the context window size of Kat Coder Pro V2?

Kat Coder Pro V2 has a context window of 256K tokens, supporting large codebases and multi-file tasks in a single context.

How does V2 differ from V1?

V2 has a context window of 256K tokens and max output of 256K tokens. Both models share the same core capabilities: parallel tool calling, multi-turn interaction, and coverage of eight software engineering task types.

What is the pricing for Kat Coder Pro V2?

Check the pricing panel on this page for today's numbers. AI Gateway tracks rates across every provider that serves Kat Coder Pro V2.

Which providers serve Kat Coder Pro V2?

The model is available from StreamLake through AI Gateway.

KwaiPilot

Kat Coder Pro V2

Kat Coder Pro V2 is KwaiPilot's second-generation agentic coding model with a context window of 256K tokens and max output of 256K tokens, building on the KAT-Coder series for software engineering tasks.

View API reference

Input and output price: Input $0.30, Output $1.20, Per 1M tokens
24h uptime: Loading AI Gateway uptime

Get API key Read the docs

import { streamText } from 'ai'

const result = streamText({
  model: 'kwaipilot/kat-coder-pro-v2',
  prompt: 'Why is the sky blue?'
})

Read docs

Overview Playground Providers Uptime Status API Similar About FAQ

Copy link to headingPlayground

Try out Kat Coder Pro V2 by KwaiPilot. Usage is billed to your team at API rates. Free users (those who haven't made a payment) get $5 of credits every 30 days.

Kat Coder Pro V2

Copy link to headingProviders

Route requests across multiple providers. Copy a provider slug to set your preference. Visit the docs for more info. Using a provider means you agree to their terms, listed under Legal.

Provider

Context	Max Output	Latency	Throughput	Input	Output	Cache	Web Search	Capabilities	ZDR	No Training	Free Tier	Release Date

StreamLake

Legal:Terms•Privacy

256K

$0.30/M

$1.20/M

Read$0.06/M

—

03/27/2026

Getting started

Call Kat Coder Pro V2 through AI Gateway with the AI SDK generateText and streamText functions, or through the OpenAI Chat Completions, OpenAI Responses, and Anthropic Messages APIs by changing the base URL. AI Gateway authenticates the request and routes it to an available provider.

Install the AI SDK (pnpm add ai dotenv), create an API key from the API Keys page, and set it as AI_GATEWAY_API_KEY in your environment. Full setup is covered in the text generation quickstart.

index.ts

import { generateText } from 'ai';
import 'dotenv/config';

async function main() {
  const result = await generateText({
    model: 'kwaipilot/kat-coder-pro-v2',
    prompt: 'Why is the sky blue?',
  });

  console.log(result.text);
}

main().catch(console.error);

Top-level parameters

The same Kat Coder Pro V2 request in each API format AI Gateway supports.

top-level-params.ts

import { generateText } from 'ai';
import 'dotenv/config';

async function main() {
  const result = await generateText({
    model: 'kwaipilot/kat-coder-pro-v2',
    system: 'You are a concise technical assistant.',
    prompt: 'Summarize the tradeoffs between static generation and SSR.',
    maxOutputTokens: 1024,
  });

  console.log(result.text);
}

main().catch(console.error);

Standard parameters like prompt, messages, temperature, and tools work as documented in the AI SDK docs. These are the parameters with model-specific behavior.

Parameter	Type	Required	Description
`model`	`string`	Yes	Model ID in the form `creator/model`, e.g. `kwaipilot/kat-coder-pro-v2`. AI Gateway routes the request to an available provider.
`maxOutputTokens`	`number`	No	Hard cap on generated tokens. Kat Coder Pro V2 supports up to `256,000` output tokens. Reasoning tokens count toward this limit.
`reasoning`	`'provider-default' \| 'none' \| 'minimal' \| 'low' \| 'medium' \| 'high' \| 'xhigh'`	No	Provider-agnostic reasoning effort, available in AI SDK 7 or later. Maps to the provider’s native reasoning configuration; reasoning settings under `providerOptions` take precedence when both are set. See the Reasoning section below.
`providerOptions`	`Record<string, JSONValue>`	No	AI Gateway routing options under `gateway`, plus any provider-native options under the provider’s own namespace — see the table below.

Input limits

Input	Formats	Sources	Max count	Max size	Limits
Text	—	—	—	—	Prompt and response share the 256K-token context window

Provider options

Set AI Gateway routing options under providerOptions.gateway. For provider-specific options, pass them under the provider’s namespace as documented by the AI SDK.

Learn more in the AI SDK provider docs.

provider-options.ts

import { generateText } from 'ai';
import 'dotenv/config';

async function main() {
  const result = await generateText({
    model: 'kwaipilot/kat-coder-pro-v2',
    prompt: 'Why is the sky blue?',
    providerOptions: {
      gateway: {
        only: ['streamlake'],
      },
    },
  });

  console.log(result.text);
}

main().catch(console.error);

These AI Gateway routing options apply to every model. Provider-specific options pass through under the provider’s own namespace (for example providerOptions.anthropic) exactly as documented by the AI SDK.

Parameter	Type	Required	Description
`providerOptions.gateway.only`	`string[]`	No	Restrict routing to these provider slugs. Requests fail over only within the listed providers.
`providerOptions.gateway.order`	`string[]`	No	Preferred provider order. Listed providers are tried first; unlisted providers remain available as fallbacks.
`providerOptions.gateway.sort`	`'cost' \| 'ttft' \| 'tps'`	No	Rank candidate providers by price, time to first token, or tokens per second instead of the default routing order.
`providerOptions.gateway.zeroDataRetention`	`boolean`	No	Route only to providers with a zero-data-retention policy for this model.

Routing across providers

AI Gateway serves the same model through multiple providers and fails over automatically. order expresses a preference while keeping every provider eligible; only is a hard allowlist — if none of the listed providers are available the request fails instead of falling back.

Options under a provider's own namespace (for example providerOptions.anthropic) are forwarded to that provider with the request. Providers ignore option namespaces that don't apply to them, so it is safe to set provider options alongside gateway routing options.

Reasoning

AI Gateway bridges reasoning across every API format. The AI SDK exposes a provider-agnostic top-level reasoning level (none, minimal, low, medium, high, or xhigh); the Chat Completions and Responses formats take the same effort under reasoning.effort; and the Anthropic Messages format uses a native thinking token budget. Whichever you send, the gateway maps it to the target model’s native configuration, converting between effort levels and token budgets as needed. Reasoning-related settings under providerOptions take full precedence over the top-level reasoning value and are never merged. Reasoning tokens typically count toward your output-token usage, though how they’re reported and billed varies by provider.

Learn more in the AI Gateway reasoning guide.

reasoning.ts

import { generateText } from 'ai';
import 'dotenv/config';

async function main() {
  const result = await generateText({
    model: 'kwaipilot/kat-coder-pro-v2',
    prompt: 'Explain the Monty Hall problem step by step.',
    reasoning: 'high',
  });

  console.log(result.text);
}

main().catch(console.error);

Tool calling

Expose tools the model can call. Define each tool’s inputs with a Zod schema.

tool-calling.ts

import { generateText, tool } from 'ai';
import { z } from 'zod';
import 'dotenv/config';

async function main() {
  const result = await generateText({
    model: 'kwaipilot/kat-coder-pro-v2',
    prompt: 'What is the weather in San Francisco?',
    tools: {
      getWeather: tool({
        description: 'Get the current weather for a location',
        inputSchema: z.object({ location: z.string() }),
        execute: async ({ location }) => ({ location, temperatureC: 18 }),
      }),
    },
  });

  console.log(result.text);
}

main().catch(console.error);

Copy link to headingMore models by KwaiPilot

Model

Context	Latency	Throughput	Input	Output	Cache	Web Search	Capabilities	Providers	ZDR	No Training	Free Tier	Release Date

kwaipilot/kat-coder-air-v2.5

256K

$0.15/M

$0.60/M

Read$0.03/M

—

07/10/2026

kwaipilot/kat-coder-pro-v2.5

256K

$0.74/M

$2.96/M

Read$0.15/M

—

07/10/2026

kwaipilot/kat-coder-pro-v1

256K

$0.30/M

$1.20/M

Read$0.06/M

—

11/09/2025

Copy link to headingAbout Kat Coder Pro V2

Kat Coder Pro V2 builds on KAT-Coder Pro V1 in the KAT-Coder series. The context window of 256K tokens and maximum output of 256K tokens support tasks involving large codebases or long-form code generation.

Like V1, the model targets agentic software engineering workflows: multi-file editing, issue resolution, and test case generation. It supports parallel tool calling and multi-turn interaction, the same core capabilities that define the KAT-Coder series.

You can route requests through AI Gateway to access Kat Coder Pro V2 via StreamLake. Multi-provider support adds resilience for production deployments. See https://www.streamlake.ai/ for documentation from KwaiPilot.

Copy link to headingWhat To Consider When Choosing a Provider

Configuration: Check StreamLake for current provider availability. Routing through multiple providers on AI Gateway enables automatic failover. Technical details sit at https://www.streamlake.ai/.
Zero Data Retention: Zero Data Retention is offered on a per-provider and model basis. See the documentation for details.
Authentication: AI Gateway authenticates requests using an API key or OIDC token. You do not need to manage provider credentials directly.

Copy link to headingWhen to Use Kat Coder Pro V2

Best for

Large codebase tasks: Software engineering work that benefits from a context of 256K tokens
Long-form code generation: Outputs need 256K tokens of capacity per response
Multi-file editing: Refactoring workflows span several files at once
Multi-provider resilience: Production agent pipelines benefit from routing on AI Gateway

Consider alternatives when

V1 covers your needs: KAT-Coder Pro V1 meets context and output requirements at a lower cost
Multimodal input required: You need image or document input alongside code
Simple completion model: A lighter, non-agentic completion model suffices for your use case

Copy link to headingConclusion

Kat Coder Pro V2 extends the KAT-Coder series with expanded context and output capacity. For teams that need more headroom than V1 for large codebases or long outputs, it adds that capacity with multi-provider resilience on AI Gateway.

Copy link to headingFrequently Asked Questions

What is the context window size of Kat Coder Pro V2?
Kat Coder Pro V2 has a context window of 256K tokens, supporting large codebases and multi-file tasks in a single context.
What is the maximum output token limit?
Up to 256K tokens per request.
When was Kat Coder Pro V2 released?
March 27, 2026.
How does V2 differ from V1?
V2 has a context window of 256K tokens and max output of 256K tokens. Both models share the same core capabilities: parallel tool calling, multi-turn interaction, and coverage of eight software engineering task types.
What is the pricing for Kat Coder Pro V2?
Check the pricing panel on this page for today's numbers. AI Gateway tracks rates across every provider that serves Kat Coder Pro V2.
Which providers serve Kat Coder Pro V2?
The model is available from StreamLake through AI Gateway.

Your use is subject to KwaiPilot's Terms & Privacy Policies.

Agent Stack

Core Platform

Tools

Learn

Build

Explore

Kat Coder Pro V2

Copy link to headingPlayground

Copy link to headingProviders

Copy link to headingUptime24 hours

Copy link to headingThroughput24 hours

Copy link to headingLatency24 hours

Getting started

Top-level parameters

Input limits

Provider options

Routing across providers

Reasoning

Tool calling

Copy link to headingMore models by KwaiPilot

Copy link to headingAbout Kat Coder Pro V2

Copy link to headingWhat To Consider When Choosing a Provider

Copy link to headingWhen to Use Kat Coder Pro V2

Best for

Consider alternatives when

Copy link to headingConclusion

Copy link to headingFrequently Asked Questions