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Sonnet 5 in Claude Code: Selection, Coding Fit, and API Access

How to select Sonnet 5 in Claude Code, what Anthropic documents about its coding capabilities, and how to distinguish Claude Code use from production API access.

Illustration for Sonnet 5 claude code

Short answer

Claude Code release notes document selecting Sonnet 5 with /model claude-sonnet-5. Anthropic’s model documentation lists Sonnet 5 as an active legacy model and recommends considering Sonnet 5.5, the current Sonnet model. The exact account or provider conditions for Claude Code access are not established in the cited excerpts, so check availability in your own setup. (platform.claude.com)

Select Sonnet 5 in Claude Code

  1. In Claude Code, enter /model.
  2. Choose or enter claude-sonnet-5.
  3. Use /model again to check or change the selection.

The release notes document this Claude Code selection path. It does not, by itself, establish which identifier to use in a direct API request or confirm every account and provider’s access conditions. If the model is unavailable, check the current Claude Code documentation and your configured provider’s access. (platform.claude.com)

Is Sonnet 5 a reasonable coding choice?

Anthropic describes Sonnet 5 as able to plan, use tools such as browsers and terminals, and run autonomously; its announcement also discusses Sonnet-class models’ coding and tool-use capabilities. That makes Sonnet 5 a candidate to evaluate for coding workflows involving tool use or multi-step tasks. These are broad capability statements, not a guarantee of results on a particular repository or a comparative benchmark for your workload. (anthropic.com)

Try it on a small set of representative tasks and review the results before standardizing on it. Sonnet 5 is listed as a legacy model; Anthropic recommends considering Sonnet 5.5. The cited material does not establish that either version will perform better on your specific codebase, so compare them against your own requirements. (platform.claude.com)

Claude Code versus production API access

Claude Code’s /model command selects a model for that coding workflow. A production integration instead sends requests from an application to a provider’s API; the Claude Code selection command does not establish an API identifier or endpoint.

Anthropic’s model documentation lists Sonnet 5 as available through the Claude API with the model ID claude-sonnet-5. Anthropic’s Messages API is its documented direct model-prompting interface, so use the applicable Messages API documentation for request format and requirements. The model reference lists the model as active but legacy and recommends considering migration to Sonnet 5.5. (platform.claude.com)

TokenForge access to this exact model remains unconfirmed. Do not infer availability or a TokenForge model ID from Anthropic’s listing or from a third-party provider’s claim; verify the exact model and interface with TokenForge before building against it. API charges, if applicable, are separate from Claude Code plan costs.

Bottom line

  • Claude Code: select Sonnet 5 with /model claude-sonnet-5; access conditions may depend on your setup.
  • Coding fit: Anthropic describes planning and browser/terminal tool use, but test representative tasks rather than assuming repository-specific results.
  • Production API: Anthropic lists claude-sonnet-5 for the Claude API. TokenForge support remains unconfirmed; verify provider-specific access and request details before integrating.

Sources

Claude Code Docs: Week 27, June 29–July 3, 2026

Claude Platform Docs: Claude Sonnet 5

Anthropic: Introducing Claude Sonnet 5

Claude Platform Docs: Using the Messages API

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