ACP emits generic tool metadata before completion.

In packages/opencode/src/acp/agent.ts, tool_call and tool_call_update(status=in_progress) use part.tool as the title, and toolStart() sends rawInput: {}. Only the completed update uses part.state.title and the richer input.

This means ACP clients often show bash, read, or skill while a tool is pending/running, even when a semantic title is already available in part.state.title.

Current local source still does this on v1.4.11-199-ga419f1c50.

OpenCode version

v1.4.11-199-ga419f1c50

Steps to reproduce

1. Run opencode acp with an ACP client that displays tool progress.
2. Trigger a tool with a semantic running title, for example a skill or connector-backed action.
3. Observe the pending/running tool card.
4. Compare it with the completed tool event.

Expected

Pending/running ACP events should use the best available semantic metadata:

• prefer part.state.title ?? part.tool
• prefer part.state.input ?? {}

Actual

Pending/running events use generic values:

• title: part.tool
• rawInput: {} in tool_call
• generic titles such as bash, read, skill until completion

Why this matters

Downstream ACP clients cannot render meaningful running status if the adapter only sends generic metadata before completion.