CLAUDE_CODE_TETHER_LIVE becomes a single opt-in for humble-hammock, stellar-drift and tether features

What

The environment variable CLAUDE_CODE_TETHER_LIVE now switches on a group of unreleased features together, and the feature behind tengu_humble_hammock gained new pieces.

• A new check is true when CLAUDE_CODE_TETHER_LIVE is true, the provider is first-party (Anthropic's own API) and one further check passes. The result is cached as threadsEnvOptIn.
• When that check passes, the tengu_stellar_drift and tengu_humble_hammock checks return true before any server gate is consulted. Their own variables, CLAUDE_CODE_STELLAR_DRIFT and CLAUDE_CODE_HUMBLE_HAMMOCK, still take priority, and both gates still fall back to false.
• In another first-party check, the variable also skips the custom ANTHROPIC_BASE_URL check and the first-party endpoint check.
• Tether live itself now uses the variable if set; otherwise false if a first-party condition fails; otherwise the gate tengu_curious_tower, which falls back to false. It no longer checks the base URL.
• Under humble hammock, attachment building copies tool-input copies into messages, and declared-tool entries gain an optional toolInputCopies list. One extra condition depends on a function that always returns false.
• A variant of the humble-hammock check that ignores the tether override is used for the tool-input-copies path and to register one SDK control-request schema.

The flag server returned on for tengu_stellar_drift, tengu_humble_hammock and tengu_curious_tower, both for this site's account and for the anonymous baseline, but no reading has been taken under this release yet.

Why

One environment variable now acts as the switch for this set of features, including behind a custom base URL. If you set CLAUDE_CODE_TETHER_LIVE=true, expect all of them to turn on together.