Claude Integration

Zana provides native support for Anthropic Claude models, enabling you to use Claude as your coding copilot backend. This uses the Anthropic Messages API directly — no OpenAI compatibility layer needed.

Setup

1. Get an API Key

2. Set the Environment Variable

export ANTHROPIC_API_KEY="sk-ant-..."

3. Start Zana

using Zana

zana(claude=true)

Quick Start

Default (Claude Sonnet)

using Zana

# Reads ANTHROPIC_API_KEY from environment
zana(claude=true)

Specific Model

using Zana

zana(claude=true, model="claude-opus-4-20250514")

Pass API Key Directly

using Zana

zana(claude=true, api_key="sk-ant-...")

Programmatic Usage

Use ClaudeConfig with ZanaAgent for scripting and automation:

using Zana

config = ZanaConfig(
    claude = ClaudeConfig(
        api_key = ENV["ANTHROPIC_API_KEY"],
        model = "claude-sonnet-4-20250514"
    )
)

agent = ZanaAgent(config, pwd())
result = process_turn(agent, "Explain the architecture of this project")

println(result.response)
println("Tokens: $(result.input_tokens) in / $(result.output_tokens) out")

Configuration

`ClaudeConfig`

ClaudeConfig(;
    api_key::String,
    model::String = "claude-sonnet-4-20250514",
    base_url::String = "https://api.anthropic.com",
    max_tokens::Int = 8192,
    temperature::Float64 = 0.1,
    api_version::String = "2023-06-01",
)

Field	Type	Default	Description
`api_key`	`String`	required	Anthropic API key
`model`	`String`	`"claude-sonnet-4-20250514"`	Claude model identifier
`base_url`	`String`	`"https://api.anthropic.com"`	API base URL
`max_tokens`	`Int`	`8192`	Maximum tokens in response
`temperature`	`Float64`	`0.1`	Sampling temperature
`api_version`	`String`	`"2023-06-01"`	Anthropic API version header

For the full configuration reference, see Configuration.

Available Models

Model	Identifier	Strengths
Claude Sonnet 4	`claude-sonnet-4-20250514`	Great balance of speed and capability (default)
Claude Opus 4	`claude-opus-4-20250514`	Most capable, best for complex tasks
Claude Haiku 3.5	`claude-haiku-4-5-20251001`	Fastest, good for simple tasks

Model Selection

Claude Sonnet 4 is the default and recommended for most coding tasks. Use Opus for complex multi-file refactoring or architecture tasks. Use Haiku for quick questions and simple edits.

How It Works

The Anthropic Messages API differs from OpenAI in several ways. Zana handles all of these automatically:

Authentication — Uses x-api-key header instead of Authorization: Bearer
System prompt — Sent as a top-level system parameter, not as a message
Tool format — Tools use input_schema instead of parameters, without the {"type":"function","function":{...}} wrapper
Tool results — Sent as user role messages with tool_result content blocks
Content blocks — Responses use typed content blocks (text, tool_use) instead of plain strings

Troubleshooting

Problem: HTTP.StatusError with 401

Solution: Check that your ANTHROPIC_API_KEY is valid and not expired

Problem: HTTP.StatusError with 429

Solution: You've hit the rate limit. Wait a moment and try again, or check your Anthropic plan limits

Problem: HTTP.StatusError with 400

Solution: The model name may be invalid. Check available models at docs.anthropic.com

Problem: Responses seem truncated

Solution: Increase max_tokens in ClaudeConfig. The default is 8192, but you can set it higher: ```julia zana(claude=true) # uses 8192 by default
Or with programmatic API:
ClaudeConfig(apikey="...", maxtokens=16384) ```

Or with programmatic API: