add-compact

name	add-compact
description	Add /compact command for manual context compaction. Solves context rot in long sessions by forwarding the SDK's built-in /compact slash command. Main-group or trusted sender only.

Add /compact Command

Adds a /compact session command that compacts conversation history to fight context rot in long-running sessions. Uses the Claude Agent SDK's built-in /compact slash command — no synthetic system prompts.

Session contract: /compact keeps the same logical session alive. The SDK returns a new session ID after compaction (via the init system message), which the agent-runner forwards to the orchestrator as newSessionId. No destructive reset occurs — the agent retains summarized context.

Phase 1: Pre-flight

Check if src/session-commands.ts exists:

test -f src/session-commands.ts && echo "Already applied" || echo "Not applied"

If already applied, skip to Phase 3 (Verify).

Phase 2: Apply Code Changes

Merge the skill branch:

git fetch upstream skill/compact
git merge upstream/skill/compact

Note: upstream is the remote pointing to aer-org/art. If using a different remote name, substitute accordingly.

This adds:

• src/session-commands.ts (extract and authorize session commands)
• src/session-commands.test.ts (unit tests for command parsing and auth)
• Session command interception in src/index.ts (both processGroupMessages and startMessageLoop)
• Slash command handling in container/agent-runner/src/index.ts

Validate

npm test
npm run build

Rebuild container

./container/build.sh

Phase 3: Verify

Validate

npm run build
npm test
./container/build.sh

Integration Test

1. Run art compose and start the agent
2. Send /compact in the chat
3. Verify:
   • The agent acknowledges compaction
   • The session continues — send a follow-up message and verify the agent responds coherently
   • Container logs show Compact boundary observed (confirms SDK actually compacted)

Notes

• Session continues after compaction. This is not a destructive reset. The conversation continues with summarized context.
• No auto-compaction. This skill implements manual compaction only.
• No changes to the container image, Dockerfile, or build script.