JA EN
shiichan

Claude Code v2.1.284: Sonnet 5.5 becomes the default, plus /mcp reconnect all

Claude Code Release ★★★★ View Markdown
#anthropic#ai#devops

Hi everyone, Shii-chan here! Today I'm covering a new Claude Code release.

Claude Code Release github.com

What was announced?

Claude Code's release page published v2.1.284. The GitHub release notes list new features, a lot of bug fixes, and behavior changes.

The story so far

The default Sonnet used to be a different model. From this release, Claude Sonnet 5.5 (claude-sonnet-5-5) is the default Sonnet on the Anthropic API.

What changes

Here are the main additions:

  • Claude Sonnet 5.5: 1M context, $2/$10 per Mtok, with $0.20/Mtok cache reads
  • A "Yes, but ask again next time" answer on auto mode's prompt before a read outside the working directories, so you can allow that one read and still be asked about later ones
  • /mcp reconnect all: retries every MCP server that failed to connect or needs authentication at once
  • /rate-limit-options added to /help and the command menu, for claude.ai subscribers
  • Dollar amounts for the spend limit in /usage and the status line, such as "$271.40 / $500.00 spent this month", when the gateway runs this version or later

Dive Deep

Around configuration, there are these additions:

  • New keybinding actions effortSlider:decreaseEffort, increaseEffort, and toggleUltracode, so the /effort slider's arrow and Tab keys can be rebound in keybindings.json
  • The status line's rate_limits.spend_limit gains used_usd, limit_usd, and period
  • Claude apps gateway: startup warnings when a managed policy's availableModels is empty and similar cases. Setting auth: { google: {} } on telemetry.forward_to exports telemetry straight to Google Cloud's OTLP endpoint. There's also certificate client authentication with private_key_jwt between the gateway and the identity provider

There are behavior changes too:

  • The interactive terminal and VS Code now start in auto mode by default
  • Ultracode is now a separate toggle in /effort
  • The non-interactive first turn waits up to 2 seconds for MCP servers

There are many bug fixes, for example:

  • Damaged response streams showing raw errors or "undefined"
  • Prompt-too-long errors persisting after compacting (it now recompacts)
  • MCP tool calls failing in resumed sessions
  • claude mcp add claiming success when restricted by managed settings

The release also includes changes to the VS Code extension (message timestamps, an Ultracode switch, and more), cloud sessions, and Claude Tag (Slack). See the GitHub release notes for the full list.

Wrap-up

  • Claude Sonnet 5.5 is now the default Sonnet on the Anthropic API
  • Auto mode prompts are finer-grained, and /mcp reconnect all makes reconnecting MCP servers easier
  • Spend limits are now visible in dollar amounts
  • The interactive terminal and VS Code start in auto mode by default
  • Lots of bug fixes, plus VS Code and Claude Tag improvements

If you use Claude Code every day, update and check out the new defaults!

Related posts