Sweep 22 Sep 2026 · 17:19Z Build v2.1.280 501 read Stable v2.1.267 Latest v2.1.280 Next v2.1.280 Feeds RSS JSON llms.txt Unofficial
System reminder: read empty

v2.1.280, what moved

SDK-CLI Agent SDK, print mode. 2 added and 16 removed, of 55 lines, about 571 words, in the prompt all 1 arms receive. 2 of 20 tool descriptions changed. The appended system-reminder blocks moved: 5 lines added, 2 lines removed. Compared against v2.1.278.

This is the system reminder: read empty request, captured on its own. Its system array, its tools and every count below are this request's, not the ordinary one's. The injected-prompt ledger lists every surface the rig reaches.

Releasedcaptured
Compared withv2.1.278the previous capture on this arm
Prompt55 ln1 family, 5,638 characters
Model strings1every capture asks all of them
Tool descriptions20 2 moved this release, 20 with a parameter schema
Appended after it1 block8,140 more characters on the wire This changeas markdownfor diffing it yourself
1 capture arm for this release, one page each, never diffed against each other

The system reminder: read empty

1 What the client sends for this surface, as it went on the wire. This is the prompt the capture was taken for; the system array below it is the rest of the same request.

read-empty · 1 line, 52 characters · Same as v2.1.278

Warning: the file exists but the contents are empty.

What changed since the previous capture

3 One line per document that moved, the system prompt and the tool descriptions in the same table.
PromptReachMovedThe first line that changed
System prompt 55 ln all 1 arms +2−16 - The most recent Claude models are the Claude 5 family and Haiku 4.5. Model IDs — Fable 5.1: 'claude-fable-5-1', Opus 5: 'claude-opus-5', Sonnet 5:...
Agent 15 ln all 1 arms +1−1 For a single-fact lookup where you already know the file, symbol, or value, search directly. Once you've delegated a search, don't also run it yoursel...
Bash 12 ln all 1 arms +0−1 - IMPORTANT: Avoid using this tool to run `cat`, `head`, `tail`, `sed`, `awk`, or `echo` commands, unless explicitly instructed or after you have veri...

The families in this capture

1 A family is one prompt and every model-interpolated copy of it, ranked by the model strings it reaches.
#FamilyHeadReachCopiesOpens with
1 (unset) 55 ln · 5.6k 1 of 1 1 copy You are an interactive agent that helps users with software engineering tasks.

Tool descriptions

20 The text the model is given for each tool, on this arm.
All 20 tool descriptions →
ToolDescriptionCopiesMoved
Agent 1,668 chars 1 moved
Bash 919 chars 1 moved
CronCreate 2,924 chars 1 same
CronDelete 167 chars 1 same
CronList 106 chars 1 same
Edit 360 chars 1 same
EnterWorktree 3,220 chars 1 same
ExitWorktree 1,923 chars 1 same
ListAgents 777 chars 1 same
NotebookEdit 619 chars 1 same
Read 790 chars 1 same
ReportFindings 574 chars 1 same
ScheduleWakeup 3,396 chars 1 same
SendMessage 4,259 chars 1 same
Skill 1,417 chars 1 same
TaskStop 378 chars 1 same
WebFetch 469 chars 1 same
WebSearch 312 chars 1 same
Workflow 3,480 chars 1 same
Write 240 chars 1 same
Read the whole system prompt → - The most recent Claude models are the Claude 5 family and Haiku 4.5. Model IDs — Fable 5.1: 'claude-fable-5-1', Opus 5...