An entry is only as true as the day it was written.
Flags move on the server after a release ships. Anthropic's own notes land days later and their documentation later still. Sometimes an entry turns out to be wrong and gets corrected by hand. All of that is recorded against the entry it happened to, and this is the whole of it in the order it happened.
Nothing here replaces an entry. Every line links to the page its release published, still saying what that release said, because a correction is added and dated rather than swapped in.
| When | Entry | What happened |
|---|---|---|
v2.1.257claude-fable-5 |
Documentation arrivedA small documentation edit on Or, for the model with the same capabilities and no access approval requirement: touched a line naming claude-fable-5 after this was published.
the line in the docs* If you replay conversation history on an earlier model, strip `thinking` and `redacted_thinking` blocks from prior assistant turns first. Thinking blocks from `claude-fable-5` and `claude-mythos-5` are readable only by the model that pro… |
|
v2.1.246mythos-5 |
Documentation arrivedA small documentation edit on Or, for the model with the same capabilities and no access approval requirement: touched a line naming mythos-5 after this was published.
the line in the docs* If you replay conversation history on an earlier model, strip `thinking` and `redacted_thinking` blocks from prior assistant turns first. Thinking blocks from `claude-fable-5` and `claude-mythos-5` are readable only by the model that pro… |
|
v2.1.257fable-5-1 |
Documentation arrivedA small documentation edit on whats-new-fable-5-1 touched a line naming fable-5-1 after this was published.
the line in the docsTo keep thinking valid across a long session, treat the conversation as append-only. Add instructions with a [mid-conversation system message](https://platform.claude.com/docs/en/build-with-claude/mid-conversation-system-messages) ([turn-s… |
|
v2.1.257fable-5-1 |
Documentation arrivedA small documentation edit on whats-new-fable-5-1 touched a line naming fable-5-1 after this was published.
the line in the docsTo keep thinking valid across a long session, treat the conversation as append-only. Add instructions with a [mid-conversation system message](https://platform.claude.com/docs/en/build-with-claude/mid-conversation-system-messages) ([turn-s… |
|
v2.1.257action |
Documentation arrivedA small documentation edit on whats-new-fable-5-1 touched a line naming action after this was published.
the line in the docsTo keep thinking valid across a long session, treat the conversation as append-only. Add instructions with a [mid-conversation system message](https://platform.claude.com/docs/en/build-with-claude/mid-conversation-system-messages) ([turn-s… |
|
v2.1.257/compact |
Documentation arrivedA small documentation edit on whats-new-fable-5-1 touched a line naming /compact after this was published.
the line in the docsTo keep thinking valid across a long session, treat the conversation as append-only. Add instructions with a [mid-conversation system message](https://platform.claude.com/docs/en/build-with-claude/mid-conversation-system-messages) ([turn-s… |
|
v2.1.248/compact |
Documentation arrivedA small documentation edit on whats-new-fable-5-1 touched a line naming /compact after this was published.
the line in the docsTo keep thinking valid across a long session, treat the conversation as append-only. Add instructions with a [mid-conversation system message](https://platform.claude.com/docs/en/build-with-claude/mid-conversation-system-messages) ([turn-s… |
|
v2.1.246fable-5 |
Documentation arrivedA small documentation edit on whats-new-fable-5-1 touched a line naming fable-5 after this was published.
the line in the docsTo keep thinking valid across a long session, treat the conversation as append-only. Add instructions with a [mid-conversation system message](https://platform.claude.com/docs/en/build-with-claude/mid-conversation-system-messages) ([turn-s… |
|
v2.1.260/context |
Documentation arrivedA small documentation edit on whats-new-fable-5-1 touched a line naming /context after this was published.
the line in the docsTo keep thinking valid across a long session, treat the conversation as append-only. Add instructions with a [mid-conversation system message](https://platform.claude.com/docs/en/build-with-claude/mid-conversation-system-messages) ([turn-s… |
|
v2.1.252/context |
Documentation arrivedA small documentation edit on whats-new-fable-5-1 touched a line naming /context after this was published.
the line in the docsTo keep thinking valid across a long session, treat the conversation as append-only. Add instructions with a [mid-conversation system message](https://platform.claude.com/docs/en/build-with-claude/mid-conversation-system-messages) ([turn-s… |
|
v2.1.248/context |
Documentation arrivedA small documentation edit on whats-new-fable-5-1 touched a line naming /context after this was published.
the line in the docsTo keep thinking valid across a long session, treat the conversation as append-only. Add instructions with a [mid-conversation system message](https://platform.claude.com/docs/en/build-with-claude/mid-conversation-system-messages) ([turn-s… |
|
v2.1.248/context |
Documentation arrivedA small documentation edit on whats-new-fable-5-1 touched a line naming /context after this was published.
the line in the docsTo keep thinking valid across a long session, treat the conversation as append-only. Add instructions with a [mid-conversation system message](https://platform.claude.com/docs/en/build-with-claude/mid-conversation-system-messages) ([turn-s… |
|
v2.1.232/context |
Documentation arrivedA small documentation edit on whats-new-fable-5-1 touched a line naming /context after this was published.
the line in the docsTo keep thinking valid across a long session, treat the conversation as append-only. Add instructions with a [mid-conversation system message](https://platform.claude.com/docs/en/build-with-claude/mid-conversation-system-messages) ([turn-s… |
|
v2.1.232/context |
Documentation arrivedA small documentation edit on whats-new-fable-5-1 touched a line naming /context after this was published.
the line in the docsTo keep thinking valid across a long session, treat the conversation as append-only. Add instructions with a [mid-conversation system message](https://platform.claude.com/docs/en/build-with-claude/mid-conversation-system-messages) ([turn-s… |
|
v2.1.232/context |
Documentation arrivedA small documentation edit on whats-new-fable-5-1 touched a line naming /context after this was published.
the line in the docsTo keep thinking valid across a long session, treat the conversation as append-only. Add instructions with a [mid-conversation system message](https://platform.claude.com/docs/en/build-with-claude/mid-conversation-system-messages) ([turn-s… |
|
v2.1.259pin |
Documentation arrivedA small documentation edit on errors touched a line naming pin after this was published.
the line in the docsWithout the `thinking-binding-controls-2026-08-01` beta header the message also names that header. Keep the conversation history append-only, or send the beta header with `prefix_mismatch_behavior: "drop_block"` to drop the block and conti… |
|
v2.1.259pin |
Documentation arrivedA small documentation edit on errors touched a line naming pin after this was published.
the line in the docsWithout the `thinking-binding-controls-2026-08-01` beta header the message also names that header. Keep the conversation history append-only, or send the beta header with `prefix_mismatch_behavior: "drop_block"` to drop the block and conti… |
|
v2.1.259pin |
Documentation arrivedA small documentation edit on errors touched a line naming pin after this was published.
the line in the docsWithout the `thinking-binding-controls-2026-08-01` beta header the message also names that header. Keep the conversation history append-only, or send the beta header with `prefix_mismatch_behavior: "drop_block"` to drop the block and conti… |
|
v2.1.259pin |
Documentation arrivedA small documentation edit on errors touched a line naming pin after this was published.
the line in the docsWithout the `thinking-binding-controls-2026-08-01` beta header the message also names that header. Keep the conversation history append-only, or send the beta header with `prefix_mismatch_behavior: "drop_block"` to drop the block and conti… |
|
v2.1.261thinking-binding-controls-2026-08-01 |
Documentation arrivedA small documentation edit on errors touched a line naming thinking-binding-controls-2026-08-01 after this was published.
the line in the docsWithout the `thinking-binding-controls-2026-08-01` beta header the message also names that header. Keep the conversation history append-only, or send the beta header with `prefix_mismatch_behavior: "drop_block"` to drop the block and conti… |
|
v2.1.261thinking-binding-controls-2026-08-01 |
Documentation arrivedA small documentation edit on errors touched a line naming thinking-binding-controls-2026-08-01 after this was published.
the line in the docsWithout the `thinking-binding-controls-2026-08-01` beta header the message also names that header. Keep the conversation history append-only, or send the beta header with `prefix_mismatch_behavior: "drop_block"` to drop the block and conti… |
|
v2.1.247tengu_cobalt_plinth_alder |
Flag reading movedThe flag server now returns on for tengu_cobalt_plinth_alder, read as this account. | |
v2.1.247tengu_cobalt_plinth_alder |
Flag reading movedThe flag server now returns on for tengu_cobalt_plinth_alder, read as this account. | |
v2.1.239tengu_cobalt_plinth_alder |
Flag reading movedThe flag server now returns on for tengu_cobalt_plinth_alder, read as this account. | |
v2.1.206tengu_umber_kestrel |
Flag reading movedThe flag server now returns on for tengu_umber_kestrel, read as this account. | |
v2.1.239tengu_toasty_breeze |
Flag reading movedThe flag server now returns {"allowanceNote":"{percent} allowance left","budgetExhaustedCopy":"You've used this week's lower-priority allowance","cooloffMinutes":10,"enabled":true,"label":"Continue now at lower priority","noticeLine":"/low-priority to continue now at lower priority · uses your weekly limit","statusLine":"Lower priority until {reset}","version":3,"waitBanner":"Working at lower priority · waiting for capacity"} for tengu_toasty_breeze, read as this account. | |
v2.1.239tengu_toasty_breeze |
Flag reading movedThe flag server now returns {"allowanceNote":"{percent} allowance left","budgetExhaustedCopy":"You've used this week's lower-priority allowance","cooloffMinutes":10,"enabled":true,"label":"Continue now at lower priority","noticeLine":"/low-priority to continue now at lower priority · uses your weekly limit","statusLine":"Lower priority until {reset}","version":3,"waitBanner":"Working at lower priority · waiting for capacity"} for tengu_toasty_breeze, read as this account. | |
v2.1.248tengu_nifty_lemur |
Flag reading movedThe flag server now returns {"autoContinue":true,"enabled":true,"label":"Reset your session limit now","noticeLine":"/limit-reset to reset your session limit now · uses weekly limit · 1/week","spentLine":"Weekly reset used · available again {date}","successLine":"Session limit reset · next reset available {date} · your weekly limit still applies","unavailableLine":"Couldn't reset your session limit right now · try again in a moment","version":1} for tengu_nifty_lemur, read as this account. | |
v2.1.248tengu_nifty_lemur |
Flag reading movedThe flag server now returns {"autoContinue":true,"enabled":true,"label":"Reset your session limit now","noticeLine":"/limit-reset to reset your session limit now · uses weekly limit · 1/week","spentLine":"Weekly reset used · available again {date}","successLine":"Session limit reset · next reset available {date} · your weekly limit still applies","unavailableLine":"Couldn't reset your session limit right now · try again in a moment","version":1} for tengu_nifty_lemur, read as this account. | |
v2.1.223tengu_juniper_relay |
Flag reading movedThe flag server now returns on for tengu_juniper_relay, read as this account. | |
v2.1.251tengu_juniper_relay |
Flag reading movedThe flag server now returns on for tengu_juniper_relay, read as this account. | |
v2.1.236disallowedTools |
Documentation arrivedAnthropic's documentation has since written up disallowedTools, on Create custom subagents.
the line in the docs| `disallowedTools` | No | Tools to deny, removed from inherited or specified list. An entry with a specifier, such as `Bash(git push *)`, still [removes the whole tool](#available-tools) | |
|
v2.1.234allowUnsandboxedCommands |
Documentation arrivedAnthropic's documentation has since written up allowUnsandboxedCommands, on Configure the sandboxed Bash tool.
the line in the docsclaude --settings '{"sandbox": {"enabled": true, "allowUnsandboxedCommands": false}}' |
|
v2.1.261--scope |
Documentation arrivedA small documentation edit on Connect Claude Code to tools via MCP touched a line naming --scope after this was published.
the line in the docs* To add or change the secret later, remove the server with `claude mcp remove <name>`, then add it again with `--client-secret` and the same `--scope` |
|
v2.1.259claude mcp remove |
Documentation arrivedA small documentation edit on Connect Claude Code to tools via MCP touched a line naming claude mcp remove after this was published.
the line in the docs* To add or change the secret later, remove the server with `claude mcp remove <name>`, then add it again with `--client-secret` and the same `--scope` |
|
v2.1.257skipDangerousModePermissionPrompt |
Documentation arrivedA small documentation edit on Connect Claude Code to tools via MCP touched a line naming skipDangerousModePermissionPrompt after this was published.
the line in the docsIn `claude -p` runs, [Agent SDK](/docs/en/headless) sessions, and [cloud sessions](/docs/en/claude-code-on-the-web), Claude Code can't show that prompt: it loads project-scoped servers without asking. Claude Code also skips the prompt in a… |
|
v2.1.257bypassPermissions |
Documentation arrivedA small documentation edit on Connect Claude Code to tools via MCP touched a line naming bypassPermissions after this was published.
the line in the docsIn `claude -p` runs, [Agent SDK](/docs/en/headless) sessions, and [cloud sessions](/docs/en/claude-code-on-the-web), Claude Code can't show that prompt: it loads project-scoped servers without asking. Claude Code also skips the prompt in a… |
|
v2.1.247bypassPermissions |
Documentation arrivedA small documentation edit on Connect Claude Code to tools via MCP touched a line naming bypassPermissions after this was published.
the line in the docsIn `claude -p` runs, [Agent SDK](/docs/en/headless) sessions, and [cloud sessions](/docs/en/claude-code-on-the-web), Claude Code can't show that prompt: it loads project-scoped servers without asking. Claude Code also skips the prompt in a… |
|
v2.1.246claude -p |
Documentation arrivedA small documentation edit on Connect Claude Code to tools via MCP touched a line naming claude -p after this was published.
the line in the docsIn `claude -p` runs, [Agent SDK](/docs/en/headless) sessions, and [cloud sessions](/docs/en/claude-code-on-the-web), Claude Code can't show that prompt: it loads project-scoped servers without asking. Claude Code also skips the prompt in a… |
|
v2.1.265Esc |
Documentation arrivedA small documentation edit on Glossary touched a line naming Esc after this was published.
the line in the docsA restore point created at each prompt you send that starts a turn. Claude Code snapshots files before every edit so a checkpoint can revert them. Press `Esc` twice or run `/rewind` to restore code, conversation, or both to an earlier poin… |
|
v2.1.233/rewind |
Documentation arrivedA small documentation edit on Glossary touched a line naming /rewind after this was published.
the line in the docsA restore point created at each prompt you send that starts a turn. Claude Code snapshots files before every edit so a checkpoint can revert them. Press `Esc` twice or run `/rewind` to restore code, conversation, or both to an earlier poin… |
|
v2.1.233/rewind |
Documentation arrivedA small documentation edit on Glossary touched a line naming /rewind after this was published.
the line in the docsA restore point created at each prompt you send that starts a turn. Claude Code snapshots files before every edit so a checkpoint can revert them. Press `Esc` twice or run `/rewind` to restore code, conversation, or both to an earlier poin… |
|
v2.1.257--all |
Documentation arrivedA small documentation edit on Fullscreen rendering touched a line naming --all after this was published.
the line in the docs* Rules you passed with [`--allowed-tools` or `--disallowed-tools`](/docs/en/cli-reference#cli-flags), and your `--agent`, `--agents`, `--append-system-prompt`, and `--system-prompt-snapshot` flags |
|
v2.1.257allowed-tools |
Documentation arrivedA small documentation edit on Fullscreen rendering touched a line naming allowed-tools after this was published.
the line in the docs* Rules you passed with [`--allowed-tools` or `--disallowed-tools`](/docs/en/cli-reference#cli-flags), and your `--agent`, `--agents`, `--append-system-prompt`, and `--system-prompt-snapshot` flags |
|
v2.1.242--append-system-prompt |
Documentation arrivedA small documentation edit on Fullscreen rendering touched a line naming --append-system-prompt after this was published.
the line in the docs* Rules you passed with [`--allowed-tools` or `--disallowed-tools`](/docs/en/cli-reference#cli-flags), and your `--agent`, `--agents`, `--append-system-prompt`, and `--system-prompt-snapshot` flags |
|
v2.1.234--append-system-prompt |
Documentation arrivedA small documentation edit on Fullscreen rendering touched a line naming --append-system-prompt after this was published.
the line in the docs* Rules you passed with [`--allowed-tools` or `--disallowed-tools`](/docs/en/cli-reference#cli-flags), and your `--agent`, `--agents`, `--append-system-prompt`, and `--system-prompt-snapshot` flags |
|
v2.1.234--agents |
Documentation arrivedA small documentation edit on Fullscreen rendering touched a line naming --agents after this was published.
the line in the docs* Rules you passed with [`--allowed-tools` or `--disallowed-tools`](/docs/en/cli-reference#cli-flags), and your `--agent`, `--agents`, `--append-system-prompt`, and `--system-prompt-snapshot` flags |
|
v2.1.267/copy |
Documentation arrivedAnthropic's documentation has since written up /copy, on Troubleshooting.
the line in the docsWhen Claude Code runs on a remote machine over SSH, it can't run a clipboard tool on your local machine. Outside tmux, when you select text in [fullscreen rendering](/docs/en/fullscreen) or run `/copy`, Claude Code sends the text to your t… |
|
v2.1.206tengu_umber_kestrel |
Flag reading movedThe flag server now returns off for tengu_umber_kestrel, read as this account. | |
v2.1.239tengu_toasty_breeze |
Flag reading movedThe flag server now returns {"enabled":false,"version":0} for tengu_toasty_breeze, read as this account. |