opencode/.changeset/canonical-tool-results.md

@opencode-ai/plugin	@opencode-ai/sdk	@opencode-ai/client	@opencode-ai/protocol
minor	minor	minor	minor

Replace the V2 tool result model with one canonical representation per fact. Tools lose structured, projection callbacks, the Structured generic, and the exported Tool.settle interpreter; tool responses carry schema-validated output, model-visible content, and optional compact JSON metadata. Code Mode receives the validated encoded output. Durable tool success stores non-empty model content plus optional metadata; failure stores one error plus the final bounded partial snapshot. Progress carries metadata only, while execute.after hooks receive the canonical terminal outcome and managed outputPaths. A one-time migration rewrites existing projected tool rows and moves provider-hosted result payloads into provider-owned result state.