Sometimes, the Claude Code tool shows an error message like the following:

API Error: Claude's response exceeded the 32000 output token maximum. To configure this behavior, set the CLAUDE_CODE_MAX_OUTPUT_TOKENS environment variable.

This is the default max token for the tool, as well as in the Opus model.

Solution 1: Review your prompt and retry

Example: In a rare situation, the model tries to output an unnecessary string. For example, when generating a dummy PNG file for testing, it uses echo with a long string. You can provide the path to a test image, instruct it to use dummy image URLs, or skip the test.

Solution 2: Adjust the environment variable as suggested

Update the max output tokens to 64000 and resume the Claude session. Note that you need to tune your model to a supported one, for example, Sonnet, instead of Opus.

$ export CLAUDE_CODE_MAX_OUTPUT_TOKENS=64000

$ claude -r