zopu-code/repos/effect/.changeset/anthropic-4-6-structured-output.md

@effect/ai-anthropic

@effect/ai-anthropic
patch

Mark the Claude 4-6 generation as supporting native structured output in getModelCapabilities. claude-opus-4-6 and claude-sonnet-4-6 support Anthropic's constrained-decoding structured output (verified against the live API), but were classified as supportsStructuredOutput: false, so generateObject fell back to a forced JSON tool instead of requesting output_config.format (json_schema). claude-opus-4-7 / claude-opus-4-8 are classified the same way for when the generated Model enum picks them up.