{"version":"2.1.302","anchor":"attribution-header-gains-project-tag-fork-subagent-gating-r","canonical_anchor":"attribution-header-gains-project-tag-fork-subagent-gating-r","heading":"Attribution block can name a project, and one fork subagent check no longer reads its variable","tier":"internal","area":"System Prompt","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.302\/e\/attribution-header-gains-project-tag-fork-subagent-gating-r","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.302","markdown":"### Attribution block can name a project, and one fork subagent check no longer reads its variable\n\nThe attribution block can now carry a project tag, and one fork subagent check now depends on remote sessions instead of `CLAUDE_CODE_FORK_SUBAGENT`\n\n**Unclear.** It is not clear whether this check is the one that decides fork mode, so whether `CLAUDE_CODE_FORK_SUBAGENT=0` still turns forking off everywhere is unsettled.\n\n**What**\n\nThe attribution block is a short block at the start of the system prompt (the standing instructions sent to the model) that carries details such as the client version. When a project is supplied, it can now also carry two project fields, `cc_project` and `cc_project_src`. Setting `CLAUDE_CODE_ATTRIBUTION_HEADER` to `0` still leaves the whole block out.\n\nA separate check tied to forked subagents has also changed. Forked subagents are helper agents that Claude starts as copies of the current conversation. The check used to pass unless `CLAUDE_CODE_FORK_SUBAGENT` was set to turn it off. It no longer reads that variable. It now fails whenever `CLAUDE_CODE_REMOTE` is set, and otherwise depends on two other internal conditions.\n\n**Why**\n\nThe second change can affect when forked subagents are available. If you rely on `CLAUDE_CODE_FORK_SUBAGENT` to turn fork mode off, note that this one check no longer looks at it.\n\n- Area: System Prompt\n- Names: `CLAUDE_CODE_ATTRIBUTION_HEADER`\n- Tier: Under the hood\n- Useful: 3\/5\n- Signal: 3\/5\n- Scope: individual\n- Heads-up: no"}