{"name":"CLAUDE_CODE_ATTRIBUTION_PROJECT","slug":"claude-code-attribution-project","family":"env","title":"Environment variables","noun":"environment variable","description":"Claude Code now recognises `CLAUDE_CODE_ATTRIBUTION_PROJECT` and drops a value that is not a valid claude.ai Project ID from saved jobs","description_source":"entry","described_by":{"version":"2.1.304","anchor":"claude-code-attribution-project-is-validated-as-a-claudeai"},"presence":{"first_seen":"2.1.304","removed_in":null,"in_current_build":true,"newest_mined":"2.1.308","builds":5,"mined_builds":149,"first_cited":{"version":"2.1.304","released_at":"2026-10-19 19:47:15","spans":1}},"aliases":[],"entries":[{"version":"2.1.305","anchor":"claude-code-attribution-project-and-attributionproject-setti","heading":"How Claude Code picks the claude.ai Project for usage reports","line":"The claude.ai Project used for usage reports now comes from an environment variable, a setting or a managed default, and bad IDs are flagged","released_at":"2026-10-20 19:29:36","reason":"found in this entry's text"},{"version":"2.1.304","anchor":"claude-code-attribution-project-is-validated-as-a-claudeai","heading":"New CLAUDE_CODE_ATTRIBUTION_PROJECT setting checked against claude.ai Project IDs","line":"Claude Code now recognises `CLAUDE_CODE_ATTRIBUTION_PROJECT` and drops a value that is not a valid claude.ai Project ID from saved jobs","released_at":"2026-10-19 19:47:15","reason":"found in this entry's text, named in this entry"},{"version":"2.1.304","anchor":"new-env-vars-to-skip-plugin-local-mcp-servers-and-gate-plugi","heading":"New environment variables can stop plugins from starting local MCP servers","line":"Setting CLAUDE_CODE_SKIP_PLUGIN_LOCAL_MCP_SERVERS keeps only remote MCP servers from plugins, and several other environment variables are new","released_at":"2026-10-19 19:47:15","reason":"found in this entry's text"},{"version":"2.1.304","anchor":"new-claude-code-attribution-project-env-var-is-forwarded","heading":"New CLAUDE_CODE_ATTRIBUTION_PROJECT environment variable passed to spawned sessions","line":"Claude Code now always passes a CLAUDE_CODE_ATTRIBUTION_PROJECT environment variable along, empty when it is not set","released_at":"2026-10-19 19:47:15","reason":"found in this entry's text, named in this entry"}],"entries_total":4,"docs":[],"docs_total":0,"gates":[],"related":[{"name":"CLAUDE_CODE_ATTRIBUTION_ANNOUNCEMENT","slug":"claude-code-attribution-announcement","description":"Boolean (`1`\/`true`\/`yes`\/`on` or `0`\/`false`\/`no`\/`off`); when unset, the `tengu_reflective_wolf` flag decides (default `true`). The value is read once and cached. When on, the Bash tool's instructions no longer contain the commit and PR attribution lines and say to end commit messages and PR bodies with \"the attribution lines given in the conversation's system-reminder, when one is present\", and the lines are sent in a system-reminder; when off, the lines are written into the Bash instructions directly."},{"name":"CLAUDE_CODE_ATTRIBUTION_HEADER","slug":"claude-code-attribution-header","description":"Set to `0` to omit the [attribution block](\/docs\/en\/llm-gateway-protocol#system-prompt-attribution-block), which carries the client version and a prompt fingerprint, from the start of the system prompt. Caching on a direct connection to the Anthropic API is unaffected either way. In some direct-connection setups, Claude Code keeps the block on [auto mode](\/docs\/en\/permission-modes#eliminate-prompts-with-auto-mode) classifier requests even when you set `0`. In [System prompt attribution block](\/docs\/en\/llm-gateway-protocol#system-prompt-attribution-block), check which connections and credentials this covers. Before v2.1.181 the block included a per-request token on custom base URLs and Microsoft Foundry connections, so on those versions set it to `0` when your LLM gateway caches on the request body or forwards requests to a third-party provider, or when you connect to Microsoft Foundry directly"},{"name":"CLAUDE_CODE_ATTRIBUTION_STATUS_TIMEOUT_MS","slug":"claude-code-attribution-status-timeout-ms","description":"Four more environment variables are now recognized and passed through by Claude Code"}],"url":"https:\/\/changelogs.core-directive.com\/reference\/env\/claude-code-attribution-project","family_url":"https:\/\/changelogs.core-directive.com\/reference\/env.json"}