The allowlist that decides which env keys in a settings file are applied to the process gains CLAUDE_CODE_TEAM_TEARDOWN_PARK_TIMEOUT_MS, MCP_CONNECTION_NONBLOCKING, CLAUDE_ENABLE_BYTE_WATCHDOG, CLAUDE_ENABLE_BYTE_WATCHDOG_BEDROCK and CLAUDE_ENABLE_STREAM_WATCHDOG. Previously these could only be set in your shell before launching. Set them once in settings instead, for example { "env": { "CLAUDE_ENABLE_STREAM_WATCHDOG": "1" } }.
- The same allowlist decides whether a settings file is flagged as carrying unrecognised env keys, so these five no longer trigger that warning.
- All five are already read elsewhere in the build; the change is only that settings can now supply them.
- The byte watchdog, which aborts a response whose byte stream stalls, checks its variable first and otherwise falls back to a server-side default that is on, so leaving it unset keeps the current behaviour.
CLAUDE_CODE_TEAM_TEARDOWN_PARK_TIMEOUT_MS, CLAUDE_ENABLE_BYTE_WATCHDOG_BEDROCK
Strings lifted out of the shipped bundle, so the claim above can be checked against them.
The entry above is what we published on the day. These lines were added later, as Anthropic's own pages caught up, and they sit beside the original rather than replacing it.
| `MCP_CONNECTION_NONBLOCKING` | Controls whether startup waits for MCP servers to connect before the first query. MCP startup is non-blocking by default: servers connect in the background and their tools become available as they finish. S…env-vars see the edit
Anthropic's documentation has since written up MCP_CONNECTION_NONBLOCKING, on Environment variables.