Anthropic SDK for Ruby 1.69.0

Use these requirements when building Ruby applications with anthropic 1.69.0. Apply the included Ruby 4.0 baseline first.

Version and API surface

• Lock the anthropic gem in Gemfile.lock and review behavior before upgrading. The gem ships every change, fixes included, as a new release on one line, usually a new minor, and hasn't patched an older release, so write its Gemfile requirement to admit new minors rather than a patch-level ~> that would stop bundle update --conservative anthropic short of a fix. Its gemspec accepts Ruby 3.2.0 and later, but Ruby 3.2 is end-of-life; use a maintained runtime consistent with the included baseline.
• Validate application inputs before constructing SDK parameters and security-relevant response fields before use. Generated models, permissive hashes, unknown fields, and type coercion do not enforce tenant authorization or business constraints.
• Allowlist the model IDs, beta headers, resource methods, and versioned tools the application may use. Treat a new model, beta contract, or unknown security-relevant response variant as requiring review.

Credentials, workspaces, and endpoints

• Prefer Workload Identity Federation for workloads with a trusted identity provider; otherwise use a dedicated service account key from a secret manager. Constrain the federation rule's issuer, audience, workload claims, service account, workspace, and permissions; the Ruby WorkloadIdentity constructor's scope: argument does not narrow the server-granted scope.
• Configure one credential source. Explicit non-nil constructor