Reuse context. Keep a recovery path.

Three different things

Mechanism	What it holds	How you use it
Read cache	Prior representations and source references	An unchanged re-read can return a compact reference
Output archive	Large tool output retained outside the prompt	Follow the identifier with ctx_expand
Project knowledge	Selected findings, decisions and relationships	Recall with ctx_knowledge

A cache hit is not durable knowledge. An archived command result is not a live view of the repository.

Refresh a file

Ask for a fresh read when a reference is insufficient or the task needs current text:

{"name":"ctx_read","arguments":{"path":"README.md","mode":"full","fresh":true}}

Use raw: true when exact file text matters. Security processing still applies on supported paths.

Retrieve an archive

When a result includes an archive ID or path, pass that returned value to ctx_expand. Its schema supports targeted retrieval: search, line ranges, head, tail and JSON selection.

Searching an archive often gives the needed error or record without sending the entire output again. Do not invent an identifier or treat an example ID as a real source.

Respect retention

Archives are bounded by age and disk limits. Cache cleanup, source changes and access restrictions can make recovery unavailable. Store durable evidence deliberately when a workflow needs it; a recovery handle is not an indefinite backup.

The configuration reference lists the actual archive defaults. The read reference distinguishes caching controls from output modes.

Keep edits exact

Do not write summaries, omission markers or archived-output notices into source code. Recover the relevant original, check that it is current, then edit. This is especially important when an agent has only seen a signature or compressed view.

Sources & versions4 references · Reviewed 17 Sept 2026

• dedup_hook.rsrust/src/tools/ctx_read/dedup_hook.rsGitHub
• ctx_retrieve.rsrust/src/tools/registered/ctx_retrieve.rsGitHub
• ctx_expand.rsrust/src/tools/ctx_expand.rsReviewed checkout
• 02-daily-use.mddocs/reference/02-daily-use.mdReviewed checkout

Core checkout

0ce2207ee4

Installed runtime

3.10.2

SDK release

1.1.0

Separate baselines for source, CLI/configuration and SDK contracts. Review does not certify every platform or integration.

Versions & compatibility