Unofficial Anthropic SDK in Go

This project provides an unofficial Go SDK for Anthropic, a A next-generation AI assistant for your tasks, no matter the scale. The SDK makes it easy to interact with the Anthropic API in Go applications. For more information about Anthropic, including API documentation, visit the official Anthropic documentation.

Installation

You can install the Anthropic SDK in Go using go get:

go get github.com/madebywelch/anthropic-go/v2

Usage

To use the Anthropic SDK, you'll need to initialize a client and make requests to the Anthropic API. Here's an example of initializing a client and performing a regular and a streaming completion:

Completion Example

package main

import (
	"fmt"

	"github.com/madebywelch/anthropic-go/v2/pkg/anthropic"
	"github.com/madebywelch/anthropic-go/v2/pkg/anthropic/utils"
)

func main() {
	client, err := anthropic.NewClient("your-api-key")
	if err != nil {
		panic(err)
	}

	prompt, err := utils.GetPrompt("Why is the sky blue?")
	if err != nil {
		panic(err)
	}

	request := anthropic.NewCompletionRequest(
		prompt,
		anthropic.WithModel[anthropic.CompletionRequest](anthropic.ClaudeV2_1),
		anthropic.WithMaxTokens[anthropic.CompletionRequest](100),
	)

	// Note: Only use client.Complete when streaming is disabled, otherwise use client.CompleteStream!
	response, err := client.Complete(request)
	if err != nil {
		panic(err)
	}

	fmt.Printf("Completion: %s\n", response.Completion)
}

Completion Example Output

The sky appears blue to us due to the way the atmosphere scatters light from the sun

Completion Streaming Example

package main

import (
	"fmt"

	"github.com/madebywelch/anthropic-go/v2/pkg/anthropic"
	"github.com/madebywelch/anthropic-go/v2/pkg/anthropic/utils"
)

func main() {
	client, err := anthropic.NewClient("your-api-key")
	if err != nil {
		panic(err)
	}

	prompt, err := utils.GetPrompt("Why is the sky blue?")
	if err != nil {
		panic(err)
	}

	request := anthropic.NewCompletionRequest(
		prompt,
		anthropic.WithModel[anthropic.CompletionRequest](anthropic.ClaudeV2_1),
		anthropic.WithMaxTokens[anthropic.CompletionRequest](100),
		anthropic.WithStreaming[anthropic.CompletionRequest](true),
	)

	// Note: Only use client.CompleteStream when streaming is enabled, otherwise use client.Complete!
	resps, errs := client.CompleteStream(request)

	for {
		select {
		case resp := <-resps:
			fmt.Printf("Completion: %s\n", resp.Completion)
		case err := <-errs:
			panic(err)
		}
	}
}

Completion Streaming Example Output

There
are
a
few
reasons
why
the
sky
appears

Messages Example

package main

import (
	"fmt"

	"github.com/madebywelch/anthropic-go/v2/pkg/anthropic"
)

func main() {
	client, err := anthropic.NewClient("your-api-key")
	if err != nil {
		panic(err)
	}

	// Prepare a message request
	request := anthropic.NewMessageRequest(
		[]anthropic.MessagePartRequest{{Role: "user", Content: []anthropic.ContentBlock{anthropic.NewTextContentBlock("Hello, world!")}}},
		anthropic.WithModel[anthropic.MessageRequest](anthropic.ClaudeV2_1),
		anthropic.WithMaxTokens[anthropic.MessageRequest](20),
	)

	// Call the Message method
	response, err := client.Message(request)
	if err != nil {
		panic(err)
	}

	fmt.Println(response.Content)
}

Messages Example Output

{ID:msg_01W3bZkuMrS3h1ehqTdF84vv Type:message Model:claude-2.1 Role:assistant Content:[{Type:text Text:Hello!}] StopReason:end_turn Stop: StopSequence:}

Messages Streaming Example

package main

import (
	"fmt"
	"os"

	"github.com/madebywelch/anthropic-go/v2/pkg/anthropic"
)

func main() {
	apiKey, ok := os.LookupEnv("ANTHROPIC_API_KEY")
	if !ok {
		fmt.Printf("missing ANTHROPIC_API_KEY environment variable")
	}
	client, err := anthropic.NewClient(apiKey)
	if err != nil {
		panic(err)
	}

	// Prepare a message request
	request := anthropic.NewMessageRequest(
		[]anthropic.MessagePartRequest{{Role: "user", Content: "Hello, Good Morning!"}},
		anthropic.WithModel[anthropic.MessageRequest](anthropic.ClaudeV2_1),
		anthropic.WithMaxTokens[anthropic.MessageRequest](20),
		anthropic.WithStreaming[anthropic.MessageRequest](true),
	)

	// Call the Message method
	resps, errors := client.MessageStream(request)

	for {
		select {
		case response := <-resps:
			if response.Type == "content_block_delta" {
				fmt.Println(response.Delta.Text)
			}
			if response.Type == "message_stop" {
				fmt.Println("Message stop")
				return
			}
		case err := <-errors:
			fmt.Println(err)
			return
		}
	}
}

Messages Streaming Example Output

Good
 morning
!
 As
 an
 AI
 language
 model
,
 I
 don
't
 have
 feelings
 or
 a
 physical
 state
,
 but

Messages Tools Example

package main

import (
	"github.com/madebywelch/anthropic-go/v2/pkg/anthropic"
)

func main() {
	client, err := anthropic.NewClient("your-api-key")
	if err != nil {
		panic(err)
	}

	// Prepare a message request
	request := &anthropic.MessageRequest{
		Model:             anthropic.Claude3Opus,
		MaxTokensToSample: 1024,
		Tools: []anthropic.Tool{
			{
				Name:        "get_weather",
				Description: "Get the weather",
				InputSchema: anthropic.InputSchema{
					Type: "object",
					Properties: map[string]anthropic.Property{
						"city": {Type: "string", Description: "city to get the weather for"},
						"unit": {Type: "string", Enum: []string{"celsius", "fahrenheit"}, Description: "temperature unit to return"}},
					Required: []string{"city"},
				},
			},
		},
		Messages: []anthropic.MessagePartRequest{
			{
				Role: "user",
				Content: []anthropic.ContentBlock{
					anthropic.NewTextContentBlock("what's the weather in Charleston?"),
				},
			},
		},
	}

	// Call the Message method
	response, err := client.Message(request)
	if err != nil {
		panic(err)
	}

	if response.StopReason == "tool_use" {
		// Do something with the tool response
	}
}

Contributing

Contributions to this project are welcome. To contribute, follow these steps:

• Fork this repository
• Create a new branch (git checkout -b feature/my-new-feature)
• Commit your changes (git commit -am 'Add some feature')
• Push the branch (git push origin feature/my-new-feature)
• Create a new pull request

License

This project is licensed under the Apache License, Version 2.0 - see the LICENSE file for details.