[Question] OpenCode V2 server API 兼容性与支持计划

Read src/opencode_a2a/opencode_upstream_client.py at lines 413-428, 454-473, 831-867 to see current V1 API calls. Review the linked OpenCode V2 migration guide for breaking changes to /api/session and /api/event. 'Done' is a maintainer response clarifying V2 support plans or a decision on documenting tested versions.

背景与使用需求

想用标准 A2A 客户端访问 OpenCode，并复用其会话能力。当前本地安装的是 OpenCode v2.0.28，因此想先确认本项目对 OpenCode V2 的兼容性与支持计划。

这是一个讨论 / 兼容性咨询，不是已复现的 bug 报告：尚未运行本适配器对接 v2.0.28 的端到端测试。仓库未启用 GitHub Discussions，因此在这里提问。

静态阅读中看到的情况

在当前源码快照 5d4700204445ce658361010cbda2fd344bc60dec 中，上游客户端仍调用：

• POST /session（L454–473）
• POST /session/{session_id}/message，使用 parts 请求体（L831–867）
• GET /event（L413–428）

而 OpenCode V2 的迁移文档说明 server API 已发生不兼容变更；V2 API 使用 /api/session、/api/event 及 /api/session/{sessionID}/prompt 等接口，因此看起来不仅是 base URL 的调整。

也看到了 #538，但理解其 “V2 lifecycle migration” 指的是 a2a-sdk 的 handler / task store 生命周期，并非 OpenCode V2 server API 的迁移。如有理解错误，欢迎纠正。

想请教的问题

1. 当前支持或实际验证的 OpenCode server 版本范围是什么？OpenCode V2 是否已有可用的分支、PR 或兼容方式？
2. 是否计划适配 OpenCode V2？如果已有相关 issue / roadmap，能否指一下入口？
3. 如果尚未计划，是否愿意接受 V2 适配贡献？更倾向于 V1/V2 双栈兼容，还是在新的版本线切换到 V2？
4. 能否在 README / compatibility 文档明确列出测试过的 OpenCode 版本，并区分 OpenCode V2 与 a2a-sdk V2？这样能帮助使用者在部署前判断是否适配。

范围与边界

关注的是 OpenCode 上游 API 的兼容性及版本说明，不是修改标准 A2A core，也不是新增 OpenCode 私有管理功能。暂不假定具体实施方案或要求交付时间。

已搜索相关 issues / PR，未找到明确跟踪 OpenCode V2 server API 支持的讨论；若有遗漏，请关联已有条目即可。谢谢！

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English version

Background and use case

I would like to access OpenCode through a standard A2A client and reuse its session capabilities. My local installation is OpenCode v2.0.28, so I would like to clarify this project's compatibility with OpenCode V2 and any plans to support it.

This is a discussion / compatibility question, not a reproduced bug report: I have not run an end-to-end test of this adapter against v2.0.28. GitHub Discussions is not enabled for the repository, so I am asking here.

Observations from static source review

At source revision 5d4700204445ce658361010cbda2fd344bc60dec, the upstream client uses:

• POST /session (lines 454–473)
• POST /session/{session_id}/message with a parts request body (lines 831–867)
• GET /event (lines 413–428)

The OpenCode V2 migration guide describes breaking server API changes. V2 uses endpoints such as /api/session, /api/event, and /api/session/{sessionID}/prompt, so adaptation appears to involve more than changing the base URL.

I also found #538, but understand its “V2 lifecycle migration” to refer to the a2a-sdk handler / task-store lifecycle, rather than migration to the OpenCode V2 server API. Please correct me if I have misunderstood.

Questions

1. Which OpenCode server versions are currently supported or tested? Is there an existing branch, PR, or compatibility approach for OpenCode V2?
2. Is OpenCode V2 support planned? If there is an existing tracking issue or roadmap, could you point me to it?
3. If it is not planned yet, would you welcome a contribution? Would you prefer dual V1/V2 compatibility or a new release line targeting V2?
4. Could the README / compatibility documentation list tested OpenCode versions and explicitly distinguish OpenCode V2 from a2a-sdk V2, to help users assess compatibility before deployment?

Scope

This concerns upstream OpenCode API compatibility and version documentation, not changes to A2A core or new OpenCode-private management features. I am not assuming a particular implementation or requesting a delivery commitment.

I searched related issues / PRs and did not find a discussion explicitly tracking OpenCode V2 server API support. If I missed one, please link the existing thread. Thank you!