2 people reported
All time, since Oct 3.
Subagent prompt cache expires
“The main session's system prompt states the session uses a 1-hour cache TTL; subagents did not get it.”
Is this your bug? What gets counted gets fixed. Pile on.
Paste this into your agent. It files your report, with your error and version.
I hit this bug: rapsheet.dev/sheets/claude-code/issues/2771/file Follow it to file my report. Show me the text before you send.
No install. No account. Public and anonymous. The link asks your agent for one report, nothing else. What it sends
Subagents use 5-minute prompt cache, rewriting full context after idle. Subagent cache writes are all ephemeral_5m_input_tokens while the main session uses 1-hour TTL, so waits over 5 minutes cause full-context re-writes.
Is this your bug?
File my report- Where
- Agent tool subagents
- Versions
- 2.1.278 to 2.1.299
- Platforms
- macOS
- How bad
- Breaks a normal workflow.
Part of: Prompt cache misses and re-writes11 bugs
- Interactive sessions get 5m cache TTL18 people
- Sleep re-sends full agent context4 people
- Warm prompt cache fully missed2 people
- Resume re-writes prompt cache3 people
- CLAUDE.md cache not shared3 people
- Cross-session prompt cache misses2 people
- Prompt cache misses after system message3 people
- Background agent summary requests12 people
- Context after prompt breaks cache4 people
- Subagent resume cache miss4 people
Not quite your bug?
- Unbounded agent context re-reads3 people
Original reports2, newest first
- Max 20x: subagents waiting on long Bash commands lose their 5-minute prompt cache and re-write full context — 54% of weekly limit in <24 h, invisible to the user#103309
- Subagents use the 5-minute prompt cache while the main session uses 1-hour; slow responses cause repeated full-context cache rewrites#99360