Zukko Blog

Guides to Claude Code, Cursor, Codex and the Claude and GPT APIs: setup, token savings and troubleshooting.

OpenAI API Keys in the Open: Why You Should Not Use Them

6 min · · API keys

Where free keys on GitHub come from, why using them is dangerous for you and for the owner, and how to protect your own key from the same leak.

GLM API Errors: Why the Request Fails and How to Fix It

5 min · · errors

A wrong model id, an overflowing 128K context, the key, the balance, limits: the typical causes of GLM API errors and a quick way to find yours.

xAI Grok API: Connecting Grok 4.7, Price and the 256K Context

4 min · · models

How to call grok-4.7 through an OpenAI-compatible API, what to do about the 256K context limit and what typical requests cost. Plus a comparison with Grok 4.6.

This organization has been disabled in the Claude API: What to Do

5 min · · errors

An Anthropic key suddenly answers "organization has been disabled". What the error is, what to check, and how to move the SDK and Claude Code to another provider.

Your Own Neural Network Proxy on Node.js: Keep the API Key Off the Frontend

4 min · · development

A small Express server between your frontend and the model API: the key stays on the server, and models, request size and rate are capped.

DeepSeek API in Python: Requests, Streaming, JSON and Error Handling

4 min · · development

Ready code for DeepSeek V4.1 Flash and V4 Pro on the OpenAI SDK: a request, streaming, JSON parsing and careful error handling.

Gemini API not working: region, key, limits and model name

6 min · · errors

Step-by-step Gemini API diagnostics: from checking status and region to a leaked key, 429 and 503 errors and a typo in the model name.

Gemini API vs Vertex API: the difference and which one to pick

5 min · · сравнение

Google offers two doors to Gemini: an AI Studio key or a Google Cloud project. We compare them and show a third route through a gateway.

Gemini API in Python: requests via the OpenAI SDK and OpenAI format

5 min · · development

A working Gemini API example in Python with no extra library: change base_url in the OpenAI SDK, add streaming and JSON, and compare with google-genai.

OpenAI API vs Anthropic API: the format differences and what to pick for your code

6 min · · API keys

Two request formats solve the same task but differ in details that break code when porting. A comparison of structure, tools, streaming, cache and headers.

Anthropic SDK for Python: base_url, key and a first request via a gateway

5 min · · development

The official anthropic package for Python just needs a different address. We cover base_url, the key, streaming, token counting, caching and errors.

The API key header: Authorization Bearer or x-api-key and where each goes

5 min · · errors

OpenAI clients send the key in Authorization, Anthropic clients in x-api-key. What the gateway accepts and how to tell from the response where the key got lost.

Claude Code security: a checklist before running the agent on a project

6 min · · development

The agent reads files and runs commands, so security settings belong before the first launch. A checklist: permissions, secrets, sandbox, a separate key with a limit.

Grok API from Russia: connecting without a foreign card

5 min · · API keys

Step by step connection to Grok 4.7, 4.6 and 4.5 through a gateway: key, address, first request in curl and Python, streaming, images and payment by SBP or crypto.

ANTHROPIC_API_KEY and ANTHROPIC_AUTH_TOKEN: where to get a key and where to set it

5 min · · API keys

Which variable the SDK needs, which one Claude Code needs, where to get a key and how to set it on Windows, macOS and Linux without it reaching git.

OpenAI API documentation in plain terms: Chat Completions by parameter

5 min · · development

A short reference to the Chat Completions endpoint. Each parameter with an example, the response and usage format, gateway-specific notes, and the cost of one reply.

Unable to connect to API (ConnectionRefused) in Claude: causes and fixes

6 min · · errors

Claude Code cannot open a connection to the API. We check the address, proxy, DNS and network with three curl commands and find the cause from the result.

AI for fixing code: how to hand over an error and get a working fix

5 min · · development

Fix quality depends on what you show the model. The data to include about the error, a prompt template, asking for a minimal diff, and verifying with a test.

LangChain.js: connect to an OpenAI-compatible API in Node.js

4 min · · development

How to point ChatOpenAI from LangChain.js at the Zukko gateway: one baseURL setting, streaming, tool calls and a spend check.

DeepSeek API OCR: extracting text from images with V4 Pro

5 min · · автоматизация

DeepSeek V4 Pro accepts images, so it can read text from screenshots and scans. Python code, a JSON mode, accuracy checks and a cost calculation for 1,000 pages.

Knowledge base in Open WebUI: RAG setup on your own documents

7 min · · автоматизация

Open WebUI lets you upload documents and ask questions about them. We show how to create a knowledge base, which settings affect answer accuracy, and what a single question costs.

Claude Sonnet 5.5 via API: connection, prices and cache at October 18, 2026

6 min · · models

How to call claude-sonnet-5-5 from Python and curl, what a typical request costs with and without cache, and how it differs from Sonnet 5 and Sonnet 4.6.

AI for SQL: how to write and optimize queries with a model

6 min · · development

Schema, sample data and a query plan in the request to the model, an EXPLAIN check and read-only access. Working Python code and a cost estimate.

LangChainGo: connecting a Go application to an OpenAI-compatible API

5 min · · development

The langchaingo library accepts any OpenAI-compatible address. We show the client, a request, streaming and a templated chain in Go, and estimate call costs.