2.1.251

All 71 changes

Every entry in the release, in source order. A release page that showed only the interesting ones would be a summary, and a summary is what this site exists to replace.

1. addedmentions: hook

   Added `PreModelSwitch` and `PostModelSwitch` hook events (block, confirm, or annotate a model switch); `SessionStart` resume hooks now receive session staleness and the estimated re-cache cost

2. added

   Added live streaming of a foreground subagent's tool calls and results to Remote Control clients (background subagents, the default, still show status only)

3. added

   Added a Spend limit bar to `/usage` and a `rate_limits.spend_limit` status line field for developers behind a Claude apps gateway with spend limits

4. added

   Added a per-session prompt-cache line to `/cost` (hit ratio, misses, tokens re-cached, warm/cold) and a matching `prompt_cache` object for status line scripts

5. added

   Added `attach`, `logs`, `stop`, `respawn`, and `rm` to `claude --help`; the `--resume` message for a running background session now names the exact `claude attach <id>` command

6. fixedmentions: permission

   Fixed file tools (Read, Write, Edit) following a symlink swapped inside the working directory after the permission check, which could read or write outside the approved location

7. fixed

   Fixed plugin commands declared in a marketplace entry being able to point outside the plugin directory; such paths are now rejected with a path-traversal error

8. fixedmentions: settings, managed settings

   Fixed project settings being able to enable detailed beta tracing or raw API body logging, and a lower-scope beta tracing endpoint bypassing an OTLP collector pinned by managed settings or a host app

9. fixedmentions: permission

   Fixed the Workflow tool reading (and quoting in errors) a `scriptPath` outside what the session may read before the permission check ran

10. fixed

    Fixed Grep and Glob not applying `Read(...)` deny rules to files reached through a symlinked search path

11. fixed

    Fixed conversations getting stuck on "text content blocks must be non-empty" errors after a turn where the model produced only thinking

12. fixed

    Fixed the first launch on a fresh install starting in default mode instead of auto mode for accounts whose startup default is auto mode

13. fixed

    Fixed Opus 5 requests failing with "effort … is not supported when thinking is disabled" when effort was xhigh/max and thinking was turned off; effort is now sent as `high` in that case

14. fixed

    Fixed replying to a message Claude Desktop delivered from another session: `SendMessage` to that session id now delivers through Claude Desktop instead of failing with "not reachable"

15. fixed

    Fixed TUI lag with many parallel subagents: per-second progress ticks now replace their predecessor instead of piling up in the transcript

16. fixed

    Fixed agent teams: a teammate's final answer not reaching the team lead — it now arrives in the idle notification instead of a content-free "available" notice

17. fixed

    Fixed background subagents being unable to reply to a message from an unnamed sibling or parent agent (`from` was the agent type, which is not an address)

18. fixedmentions: settings

    Fixed managed-settings `disableAutoMode` arriving mid-session not moving an already-running auto-mode session back to default mode

19. fixed

    Fixed a "switch to Opus 1M for 5x more context" tip that appeared even when the current Opus model already has a 1M context window

20. fixed

    Fixed Claude apps gateway sessions treating a stored Anthropic profile (e.g. a Console sign-in) as active: listing it in `/status` and retrying gateway 401s with it, though requests never use it

21. fixed

    Fixed cloud sessions telling Claude the model had changed when the host was only setting the session's initial model

22. fixed

    Fixed Remote Control reporting a failure when an organization's policy disables it; it now shows a single quiet notice instead

23. fixed

    Fixed `/mcp reconnect` on Remote Control showing a generic withheld-detail error instead of the real remedy when a server was disabled in another session

24. fixed

    Fixed `--input-format stream-json`: client-injected assistant tool calls sent without a message id were merged into the first one and their results lost, including when resuming older sessions

25. fixed

    Fixed session transcripts being silently overwritten when a directory change relocated a session onto an existing same-ID transcript

26. fixed

    Fixed background sessions and their subagents being unable to edit files inside a git worktree they created with `git worktree add`

27. fixed

    Fixed background sessions occasionally starting without any plugin skills (and staying that way) when another Claude Code process was refreshing the plugin marketplace at the same moment

28. fixed

    Fixed selecting text in an opened background session inside tmux over SSH: it now copies to the tmux buffer like a foreground session instead of falling back to OSC 52

29. fixed

    Fixed SDK and cloud sessions hanging indefinitely when an SDK MCP server's handshake acknowledgment was lost; the wait now times out after 70 seconds and marks only that server failed

30. fixed

    Fixed self-hosted runner leaving a stuck session's Bash tool processes running after the session was force-stopped

31. fixed

    Fixed `/usage-credits` for Team and Enterprise members whose admin set the org's usage-credit limit to $0: it now offers to ask the admin instead of saying a cap was reached

32. fixed

    Fixed `--worktree --tmux` with a merge-request number on a gitlab.com origin trying a doomed GitHub-style fetch first instead of fetching the GitLab ref directly

33. fixed

    Fixed Ctrl+G failing with "Emacs quit unexpectedly" in background sessions for editors that open `/dev/tty`, such as `emacs -nw` and `micro`

34. fixedmentions: settings, hook

    Fixed an `additionalDirectories` entry containing a null byte crashing startup, or breaking `/add-dir` and later settings updates when it came from an SDK host, IDE, or hook; it is now skipped

35. fixed

    Fixed the MCP server menu's copy shortcut: it now says how the sign-in URL was copied instead of always claiming success

36. fixed

    Fixed italic text (such as the session recap line) rendering as highlighted blocks in GNU screen and in tmux sessions using a `screen` terminal type

37. fixed

    Fixed `claude mcp add --header` and `claude mcp add-json` help text naming the wrong transports

38. fixed

    Fixed `claude ultrareview` and `/ultrareview` waiting the full 30 minutes when the cloud session fails to start; they now stop early and report the reason

39. fixedmentions: permission

    Fixed Bash permission checks auto-approving commands that assign an arithmetic expression to an integer shell variable (e.g. `OPTIND=1/0`, `RANDOM=2+2`); these now prompt for approval

40. fixed

    Fixed backgrounded sessions (`←`, `/background`, `--bg`) losing a Vertex/Bedrock gateway (`ANTHROPIC_*_BASE_URL` + `CLAUDE_CODE_SKIP_*_AUTH`) exported in the shell, so every request failed

41. fixed

    Fixed `claude --bg --model fable` on Max plans stopping to ask for usage credits while the interactive session on the same account still had Fable allowance

42. fixed

    Fixed the one-time "make auto mode your default" offer appearing in unattended sessions (e.g. agent-team teammate panes), where a stray keypress could accept it unread

43. fixedmentions: settings

    Fixed the managed-settings approval prompt re-appearing after signing in again to the same Claude apps gateway when the settings are unchanged

44. fixedmentions: env

    Fixed disabled `/bug` and `/share` reporting that `/feedback` was disabled; tips, `/help`, and refusal messages no longer suggest `/feedback` when an org policy or env var turns it off

45. fixed

    Fixed cloud session creation advising GitHub setup after a transient GitHub connection failure — the message now says to retry instead

46. improved

    Improved CPU usage during turns in interactive sessions by cutting redundant UI re-renders

47. improved

    Improved install size: the native binary is about 5 MB smaller

48. improved

    Improved cloud sessions: when the session's network proxy drops a connection during a Bash command, the tool result now names the host and reason instead of only "connection reset"

49. improved

    Improved `/schedule` to explain that MCP servers configured in Claude Code can't be attached to cloud routines, instead of a bare "No MCP connectors" message

50. improved

    Improved framing of messages from your own subagents: Claude is told the sender is a worker inside this session, not an unrelated Claude session

51. improved

    Improved the prompt placeholder to read "Message @name…" while viewing a background subagent or fork transcript opened from the subagent panel or `/tasks`

52. improved

    Improved sanitization of MCP server names in error messages, menus, and command results

53. improved

    Improved Amazon Bedrock session start under `CLAUDE_CODE_PROVIDER_MANAGED_BY_HOST` (e.g. Claude Desktop): a session given a Bedrock model ID or ARN no longer waits for inference-profile discovery

54. improvedmentions: settings, managed settings

    Improved the managed settings approval dialog to list only the settings that changed since you last approved them

55. improved

    Improved retry when the model's tool call is malformed: the broken output is now dropped from the retry context, including on Bedrock, Vertex, and Foundry

56. changed

    Changed `/radio` to be available on Bedrock, Vertex AI, Foundry, and Claude Platform on AWS, and when telemetry is disabled

57. changedmentions: permission

    Changed Claude in Chrome so browser actions always go through Claude Code's permission checks, including in sessions with telemetry disabled, which previously used the Chrome extension's own prompts

58. changed

    Changed `CLAUDE_CODE_SUBAGENT_MODEL` to set the default subagent model rather than override everything: an agent definition's `model:` and an explicit per-spawn model now take precedence over it

59. changed

    Changed the default commit trailer to `Co-Authored-By: Claude Code` when the active model isn't a recognized Claude model (e.g. third-party models behind a custom `ANTHROPIC_BASE_URL`)

60. changed

    Changed the default model for seat-based Enterprise subscriptions to Opus 5, matching other premium plans

61. changed

    Changed `/effort` to save your default effort level per model, so each model keeps its own setting when you switch

62. changedmentions: settings, managed settings

    Changed analytics to no longer turn off before sign-in solely because managed settings force gateway login (or cannot be read); they stay off once signed in to the gateway or via `DISABLE_TELEMETRY`

63. changedmentions: token, auth

    Changed the footer PR badge on Bedrock, Vertex, and Foundry, and when telemetry is off, to call the GitHub API directly (via `gh auth token`, `GH_TOKEN`, or `GITHUB_TOKEN`) instead of `gh pr view`

64. changedmentions: sandbox

    Changed how Bash command output files are created and read back when commands run in the sandbox, so a sandboxed command cannot redirect or replace them

65. changed

    Changed plugin/LSP install suggestions and the auto-mode default offer to wait until you've sent or cleared what you're typing, so the Enter that sends your prompt can't answer them

66. changedmentions: settings, sandbox, managed settings

    Changed server-managed settings that terminate sandbox TLS, route sandbox traffic through your own proxy, inject credentials, or weaken sandbox isolation to require approval before they apply

67. changedmentions: settings, credential

    Changed `ANTHROPIC_CUSTOM_HEADERS` from managed or project settings to require approval when it sets a credential, org/tenant, routing, or API-behavior header (e.g. `Authorization`, `Host`)

68. changedmentions: settings, env, managed settings

    Changed project-level `.claude/settings.json` `env` to no longer set `CLAUDE_CONFIG_DIR`, `CLAUDE_CODE_TMPDIR`, or `TMPDIR`/`TMP`/`TEMP`; set them in your shell, user, or managed settings instead

69. removed

    Removed syntax highlighting for six rarely used languages (1c, gml, isbl, mathematica, maxima, sqf); the binary is 2.5 MB smaller

70. fixedVSCode

    [VSCode] Fixed the sign-in screen's "Bedrock, Foundry, or Vertex" button opening the docs at the top of the page instead of the third-party provider setup section

71. changedVSCode

    [VSCode] Changed the Remote Control banner to a footer pill (shown while Remote Control is on or has failed) that opens the session on claude.ai/code; turn it on or off with `/remote-control`

Evidence

Level:

documented

Retrieved:

2026-08-29T00:00:00Z

Source:

https://raw.githubusercontent.com/anthropics/claude-code/main/CHANGELOG.md

Section sha256:

a23d7746b2f0ec584827df00294384ed153e265db2d0cef1705b8b111fc7bf73