Antigravity CLI repeats previous assistant responses in subsequent Discord replies

[partypeopleland]

Description

While testing Antigravity CLI through Discord mention-based conversations, I noticed that later replies keep re-sending content from previous turns. This makes the output grow cumulatively instead of returning only the current turn’s response.

Steps to Reproduce

1. Mention the bot in Discord to start a conversation.
2. Send a few follow-up messages.
3. Observe that each later reply includes earlier assistant responses again.

Actual Behavior

The assistant output accumulates across turns.

Example:

First reply:

AAA

Second reply:

AAA
BBB

Third reply:

AAA
BBB
CCC

Expected Behavior

Each reply should only contain the response for the current turn, without repeating previous assistant outputs.

Notes

This may indicate either:
conversation history is being appended incorrectly, or
the response buffer is being merged into subsequent turns.

Environment

OpenAB 0.8.4-beta.2

Screenshots / Logs

v0.8.4-beta.2

[CHC-Agent]

Issue at a Glance

user turn N
  → openab ACP session/prompt
  → agy-acp runs `agy --continue -p ...`
  → agy prints full accumulated conversation to stdout
  → adapter forwards stdout verbatim
  → user sees all previous responses repeated

Hi @partypeopleland,

This is the same root cause as #905 — the agy-acp adapter uses --continue which dumps the full conversation history on every turn instead of only the new response.

Related:

• bug(agy-acp): multi-turn responses repeat entire conversation history #905 — bug(agy-acp): multi-turn responses repeat entire conversation history (OPEN, by @chaodu-agent)
• PR fix(agy-acp): use --conversation ID + delta extraction for multi-turn #906 by @chaodu-agent — fix(agy-acp): use --conversation ID + delta extraction for multi-turn (OPEN, reviewed, LGTM)

PR #906 addresses this by replacing --continue with --conversation <ID> and extracting only the delta (new bytes) per turn. It has passed review and is pending merge.