Claude Code v2.1.283 · 25 Sep 2026
/context The /context
Use it now Tier: how much it should matter to you
3 Useful: my rating, 1 to 5
1 Signal: worth watching, 1 to 5
Context Area: what it touches
Improvements Kind: in v2.1.283, 25 Sep 26
What probably matters to you Section of the release
What
MCP servers are add-ons that give Claude Code extra tools, and they can send instructions that are added to the conversation. The context usage breakdown now counts those instructions, including instruction blocks added on your side, and shows them as "MCP server instructions" beside "MCP tools". Before, they had no line of their own.
The count is 0 when CLAUDE_CODE_DISABLE_ATTACHMENTS CLAUDE_CODE_SIMPLE
Why
You can see how much room lengthy MCP server instructions use, which helps when deciding which servers to keep.
How sure we are
One source agrees One thing we can check says the same as this entry.
Anthropic's release notes agree Fixed /context not counting MCP server instructions: they now appear as their own row and count toward the total
See this entry in the whole of v2.1.283 →
25 Sep 2026 · 386 entries, this one is #67.
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Open the release →
Names in this entry
slash /context Visualize current context usage as a colored grid. Shows optimization suggestions for context-heavy tools, memory bloat, and capacity warnings. When the conversation exceeds the context window, the output includes a warning showing how far over the limit you are and which command frees space. In fullscreen mode , /context collapses the per-item breakdown to keep the grid visible. Pass all to expand it
env CLAUDE_CODE_DISABLE_ATTACHMENTS Set to 1 to disable attachment processing. File mentions with @ syntax are sent as plain text instead of being expanded into file content
env CLAUDE_CODE_SIMPLE When a coordinator agent cannot use a tool, Claude is told to run it from a worker.
Anthropic's note
Upstream's own release notes for v2.1.283 name something this entry names, so the two are probably about the same change. Probably: the pairing is made on a shared name rather than on the words around it.
Fixed /context
The GitHub issue this fixes
A model matched these issues to Anthropic's notes, so a link can be wrong.
Is this right?
0 0 Feedback
What's wrong with this entry?
Hard to understand Too vague Looks wrong Not relevant to me Too long Missing the detail I wanted Duplicate of another card
Clear Learned something new I can act on this Good catch
Related
Other releases about the same thing. Found by shared names or similar wording; neither means one caused the other.
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Gateway load test mode now uses CPU closer to real traffic
Use it now Gateway
In v2.1.283 What probably matters to you release-page order
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claude plugin eval now needs git 2.31 or newer
Use it now Plugins
