{"name":"CLAUDE_CODE_DIAGNOSTICS_FILE","slug":"claude-code-diagnostics-file","family":"env","title":"Environment variables","noun":"environment variable","description":"Diagnostics logging only builds its payload when a diagnostics file is set, and never throws.","description_source":"entry","described_by":{"version":"2.1.234","anchor":"diagnostics-logging-builds-its-payload-lazily-and-swallows-f"},"presence":{"first_seen":"2.1.138","removed_in":null,"in_current_build":true,"newest_mined":"2.1.309","builds":150,"mined_builds":150,"first_cited":{"version":"2.1.299","released_at":"2026-10-14 00:23:19","spans":1}},"aliases":[],"entries":[{"version":"2.1.304","anchor":"low-disk-low-memory-watchdog-with-new-warn-thresholds","heading":"Warnings when disk space or memory runs low","line":"Claude Code can warn you, and tell Claude, when free disk space or memory drops below limits you set with two new environment variables","released_at":"2026-10-19 19:47:15","reason":"found in this entry's text"},{"version":"2.1.304","anchor":"diskmemory-watchdog-no-longer-depends-on-claude-code-diagno","heading":"Low disk and memory watchdog no longer needs the diagnostics variable","line":"The watchdog that warns about low disk space or memory no longer requires CLAUDE_CODE_DIAGNOSTICS_FILE to be set before it can start","released_at":"2026-10-19 19:47:15","reason":"found in this entry's text, named in this entry"},{"version":"2.1.299","anchor":"diagnostics-tail-snapshot-can-be-forced-by-a-caller","heading":"Tail diagnostics can run without the diagnostics variable set","line":"The tail diagnostics snapshot can now run when another part of Claude Code asks for it, even without CLAUDE_CODE_DIAGNOSTICS_FILE","released_at":"2026-10-14 00:23:19","reason":"found in this entry's text, named in this entry"},{"version":"2.1.295","anchor":"resume-diagnostics-reporter-active-only-with-claude-code-di","heading":"Diagnostics file can now record how a resumed conversation was loaded","line":"With CLAUDE_CODE_DIAGNOSTICS_FILE set, Claude Code writes a report on how each resumed conversation was loaded from its saved transcript","released_at":"2026-10-08 18:22:58","reason":"found in this entry's text, named in this entry"},{"version":"2.1.285","anchor":"sse-frame-stall-diagnostics-writer-only-active-when-claude","heading":"Diagnostics file can now record slow or stalled streaming responses","line":"With CLAUDE_CODE_DIAGNOSTICS_FILE set, Claude Code can log a record whenever a piece of a streamed response arrives slowly","released_at":"2026-09-29 17:32:09","reason":"found in this entry's text, named in this entry"},{"version":"2.1.234","anchor":"diagnostics-logging-builds-its-payload-lazily-and-swallows-f","heading":"Diagnostics logging builds its payload lazily and swallows failures","line":"Diagnostics logging only builds its payload when a diagnostics file is set, and never throws.","released_at":"2026-08-17 18:19:13","reason":"found in this entry's text"},{"version":"2.1.178","anchor":"new-environment-variables","heading":"","line":null,"released_at":"2026-06-15 19:03:37","reason":"found in this entry's text"}],"entries_total":7,"docs":[],"docs_total":0,"gates":[],"related":[{"name":"CLAUDE_CODE_3P_PROBE_WROTE_HAIKU_DEFAULT","slug":"claude-code-3p-probe-wrote-haiku-default","description":"If your cloud account cannot use a model, Claude Code can step down to the next one; `CLAUDE_CODE_DISABLE_MODEL_ACCESS_FALLBACK` turns this off"},{"name":"CLAUDE_CODE_3P_PROBE_WROTE_OPUS_DEFAULT","slug":"claude-code-3p-probe-wrote-opus-default","description":"Internal marker on third-party providers. When Claude Code itself writes `ANTHROPIC_DEFAULT_OPUS_MODEL` into its environment (the model availability probe on Bedrock, Vertex or Mantle, or a move down the model fallback ladder), it sets this variable to the same model ID. An `ANTHROPIC_DEFAULT_OPUS_MODEL` equal to it is treated as Claude Code's own choice rather than a user pin: it does not count as pinned, the probe does not skip it, and the fallback ladder may move it."},{"name":"CLAUDE_CODE_3P_PROBE_WROTE_SONNET_DEFAULT","slug":"claude-code-3p-probe-wrote-sonnet-default","description":"On third-party providers, Haiku model names are no longer skipped by the check that sets up the Sonnet default model"},{"name":"CLAUDE_CODE_3P_SEEDED_OPUS_DEFAULT","slug":"claude-code-3p-seeded-opus-default","description":"If your cloud account cannot use a model, Claude Code can step down to the next one; `CLAUDE_CODE_DISABLE_MODEL_ACCESS_FALLBACK` turns this off"},{"name":"CLAUDE_CODE_3P_SEEDED_SONNET_DEFAULT","slug":"claude-code-3p-seeded-sonnet-default","description":"If your cloud account cannot use a model, Claude Code can step down to the next one; `CLAUDE_CODE_DISABLE_MODEL_ACCESS_FALLBACK` turns this off"},{"name":"CLAUDE_CODE_ACCESSIBILITY","slug":"claude-code-accessibility","description":"Set to `1` to keep the native terminal cursor visible and disable the inverted-text cursor indicator. Allows screen magnifiers like macOS Zoom to track cursor position"},{"name":"CLAUDE_CODE_ACCOUNT_TAGGED_ID","slug":"claude-code-account-tagged-id","description":"Overrides the `user.account_id` attribute Claude Code attaches to its OpenTelemetry data. It applies only when an account UUID is known and `OTEL_METRICS_INCLUDE_ACCOUNT_UUID` is not turned off (default on); when unset or empty, `user.account_id` is derived from the account UUID as a tagged ID of the form `user_01...`."},{"name":"CLAUDE_CODE_ACCOUNT_UUID","slug":"claude-code-account-uuid","description":"The device bridge is skipped entirely when the host's account UUID doesn't match the stored one."},{"name":"CLAUDE_CODE_ACT_DONT_REDERIVE","slug":"claude-code-act-dont-rederive","description":"Three existing feature gates moved position; their defaults are unchanged."},{"name":"CLAUDE_CODE_ACTION","slug":"claude-code-action","description":"Marks a run as coming from the Claude Code GitHub Action. A truthy value (`1`, `true`, `yes` or `on`) makes Claude Code set `CLAUDE_CODE_ENTRYPOINT` to `claude-code-github-action`, but only when `CLAUDE_CODE_ENTRYPOINT` is not already set and the command is not `claude mcp serve`. It is also reported as `isClaudeCodeAction` in the environment details attached to telemetry."}],"url":"https:\/\/changelogs.core-directive.com\/reference\/env\/claude-code-diagnostics-file","family_url":"https:\/\/changelogs.core-directive.com\/reference\/env.json"}