Anthropic API Updates: Expanded Legal Protections and Messages API Beta

Anthropic has introduced new Commercial Terms of Service providing expanded copyright indemnity for customers and a beta Messages API designed to simplify prompt construction. These updates aim to provide legal certainty for enterprises and a more structured API for developers building with Claude.

Expanded Copyright Indemnity and Ownership

Anthropic's updated Commercial Terms of Service (formerly the services agreement) grant customers ownership rights over outputs generated through their use of the services. To protect users from legal risks associated with AI-generated content, Anthropic will defend customers against copyright infringement claims resulting from the authorized use of their services or outputs, and will cover the costs of approved settlements or judgments.

These terms become effective on January 1, 2024, for Claude API customers and January 2, 2024, for those using Claude via Amazon Bedrock.

The Messages API Beta

To reduce formatting errors in prompt construction—especially when prompts are dynamically constructed from user inputs—Anthropic has released the Messages API in beta. This new API shifts from a raw string prompt format to a structured array of messages, allowing developers to catch errors early in development.

Comparison of API Request Formats

Prior to the Messages API, requests were sent to the /v1/complete endpoint with a prompt string containing manually formatted roles (e.g., \n\nHuman: ... \n\nAssistant: ...).

With the Messages API, requests are sent to the /v1/messages { "model": "claude-2.1", "max_tokens": 1024, "messages": [ { "role": "user", "content": "Hello, world" }, { "role": "assistant", "content": "Hi, I'm Claude!" }, { "role": "user", "content": "Can you create a template for a quarterly executive brief?" } ] } endpoint using a structured JSON array of message objects, each specifying a role and content.

Future Roadmap and Accessibility

Anthropic is using the structured nature of the Messages API as a foundation for upcoming features. The company has explicitly stated that this transition is the first step toward offering robust function calling capabilities, which will be added to the Messages API in the future.

Additionally, Anthropic plans to broaden access to the Claude API in the coming weeks to increase availability for developers and enterprises.

Sources

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