Workbench becomes Playground, and the old tool is gone
Since August 18, Workbench in the Claude console is called Playground and has been rebuilt from the ground up. The new tool supports every Messages API parameter and ships with templates that show how code execution and web search work. For every run it displays the complete request exactly as the SDK sends it, along with the raw API response, which makes it a way to learn the API rather than only a place to try prompts. The old Workbench shut down on August 17, saved prompts and evaluations do not carry over, and the experimental prompt tools APIs for generating and improving prompts were withdrawn with it.
Workbench in the Claude console was renamed Playground on August 18 and rebuilt from the ground up. At the same time the old tool was finally shut down, along with the experimental APIs that went with it.
What is new
The last of the three below is what turns the tool from a prompt playground into a way to learn. You set parameters through the interface, see the exact code that would do the same job, and copy it into your project.
- Every Messages API parameter is supported, not just the basic set.
- Templates ship with the tool and demonstrate specific capabilities, code execution and web search.
- For every run it displays the complete request exactly as the SDK sends it, along with the raw API response.
What was shut down
The old Workbench shutdown was announced on July 17, and access ended on August 17. The carryover is not complete, and that is worth knowing in advance.
- Saved prompts, variables, and evaluations do not carry over to the new tool.
- The experimental endpoints for generating, improving, and templatizing prompts were withdrawn the same day and now return an error.
- If a script of yours called those endpoints to refine prompts automatically, it stopped working on August 17.
Why this is not just cosmetic
The rename follows a broader shift: the console is moving toward being where the API is understood, not only where it is tried. Showing the full request alongside every result reduces the gap between what works in the console and what works in code to ordinary copying.
On client work, that cuts out the dullest part of the job: checking whether a parameter was passed exactly the way the API expects it.
Sources
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