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Sweep 28 Aug 2026 · 00:00Z Build v2.1.250 478 read Stable v2.1.236 Latest v2.1.250 Next v2.1.251 Feeds RSS JSON llms.txt
Reading a new release v2.1.251 Analysing changes · 2/5 Deeper second pass · 0/5 agents 427 findings $12.75 so far

DisclaimerUnofficial, and not affiliated with Anthropic. Nearly all of this is read straight out of what ships: npm bundles, captured prompts, published docs. Anthropic's own notes go in verbatim, marked as theirs. The rest is my reading, and every entry carries the strings behind it. If one looks wrong, vote it down and say why.

Reference / Environment variables

CLAUDE_CODE_SUBAGENT_PROMPT_CACHE_TTL

A Claude Code environment variable, read out of the shipped bundle. It has been in the build since v2.1.242, including the newest one read.

What it is

You can pin the prompt cache to five minutes or an hour, separately for subagents.

Not Anthropic's. This is the line from the earliest changelog entry here that named it, v2.1.242.

Presence across releases

ReleasesReadingDeclared typeDefault
2.1.245 – 2.1.250 5 releases never mined — —
2.1.242 – 2.1.243 2 releases in the build enum —

A row reading never mined is a release with no archived bundle behind it. Nothing was read out of it, so nothing here says whether the name was in it. A declared type or a default is only ever what that release's own bundle stated.

Changelog entries naming it

  1. v2.1.242Prompt cache lifetime is now configurable

    You can pin the prompt cache to five minutes or an hour, separately for subagents.

    named in this entry

Documentation pages

A reference table page is one whose own table defines this name, and it is where the description above came from. A page that mentions it carries the name somewhere in its text and may say nothing about it at all. Every page carrying it.

Names beside it

Every environment variable in the inventory starting claude_code_subagent, up to twelve of them.

CLAUDE_CODE_SUBAGENT_CACHE_EVICTNo description from anybody. 2.1.198 CLAUDE_CODE_SUBAGENT_MODELNo description from anybody. 2.1.138

Read out of the published npm bundle release by release, and out of Anthropic's own documentation as this site captured it. Nothing on this page is a description anybody here wrote about what the environment variable does. All environment variables.