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Claude Code v2.1.275 ·

Post-turn memory: new 'memory' settings layer and MCP memory tool with read/write/append/delete, gated by CLAUDE_CODE_POST_TURN_MEMORY

A new 'memory' settings layer and MCP memory tool let Claude write, read, and edit notes across turns

TierNothing to try yethow much it should matter to you
Useful5my rating, 1 to 5
Signal5worth watching, 1 to 5
AreaMemorywhat it touches
KindIn Developmentin v2.1.275,
Nothing to try yet Notable

A new 'memory' settings layer and MCP memory tool let Claude write, read, and edit notes across turns

What

Claude Code's settings system now includes a new layer called memory, added to the existing list of layers (managed, user, project, local). Alongside it, a new internal tool exposes memory operations: memory_write, memory_read, memory_str_replace, memory_append, and memory_delete. The whole feature is gated by the environment variable CLAUDE_CODE_POST_TURN_MEMORY; when it isn't set, the related post-turn memory writing logic stays inactive. Write operations support three modes: replace, append, and insert.

Why

This lays groundwork for Claude to persist notes or state after a turn finishes and read them back later, using a dedicated settings layer and a small set of file-like operations, though it only activates when CLAUDE_CODE_POST_TURN_MEMORY is set.

Read from
Names in the bundleCLAUDE_CODE_POST_TURN_MEMORYmemory_writememory_readmemory_appendmemory_delete
What the documentation says
Since it was published

The entry above is what we published on the day. These lines were added later, as Anthropic's own pages caught up, and they sit beside the original rather than replacing it.

Added since A small documentation edit on Fetch the first page (newest activities first) and capture its trailing cursor. touched a line naming memory_delete after this was published. A `user_actor` activity does not always mean the user took the action. Processes that Anthropic runs on a user's behalf can currently appear as `user_actor` for the affected user rather than as `system_actor`, and this attribution may chan… manage-claude/compliance-activity-feed see the edit
How sure we are
One source agreesOne thing we can check says the same as this entry.
Anthropic's documentation agreesA small documentation edit on Fetch the first page (newest activities first) and capture its trailing cursor. touched a line naming…

See this entry in the whole of v2.1.275 →