Follow up MiMo Code upstream updates: per-server MCP sampling/alwaysDirectTools dropped on generate #3701

Summary

The mimocode target landed on 2026-09-28 (#3213). Since then, MiMo Code v0.1.16 has been released and main has moved on. MiMo Code's MCP server schema has two per-server keys that OpenCode does not have: sampling (released) and alwaysDirectTools (on main). Rulesync generates MCP through the OpenCode converter, which keeps only a fixed list of extra keys. Both keys are therefore dropped on generate without a warning, even though import keeps them. Separately, every source @see link of the target now returns 404.

Recent Releases

• v0.1.16 (2026-10-26) is the first release since the target was added (v0.1.15 was released on 2026-09-22). It includes the package rename from packages/opencode to packages/cli (#2591, 2026-09-30).
• Unreleased changes on main (as of 2026-10-30):
  • #2734 (2026-10-27) adds the per-server alwaysDirectTools.
  • #2737 (2026-10-28 to 2026-10-30) adds a project-config execution boundary for the Desktop Node engine.
• These files are unchanged between the target's base commit (2026-09-27) and main: config/agent.ts, config/command.ts, config/permission.ts, config/plugin.ts and session/instruction.ts. The skill loader only dropped the retired compose bundle. config.ts only removed the compose and compaction.prune keys, and rulesync writes neither.

Gaps

mcp (project + global): sampling and alwaysDirectTools are dropped on generate

• Upstream (packages/cli/src/config/mcp.ts): the local and remote server schemas both accept two keys that OpenCode does not have:
  • sampling: client-side sampling. It was added on 2026-07-30 in 014c3635 and has shipped since v0.1.10, including v0.1.16.
  • alwaysDirectTools: string[] (#2734, spec): the listed tools skip the deferred mcp_tool_search / mcp_tool_use path and are exposed as top-level tools. It is on main but not released yet.
• Rulesync: MimocodeMcp (src/features/mcp/mimocode-mcp.ts) extends OpencodeMcp. On generate, convertServerToOpencodeFormat in src/features/mcp/opencode-mcp.ts copies only OPENCODE_PASSTHROUGH_SERVER_FIELDS = ["timeout", "oauth", "protocol", "codemode"]. On import, convertOpencodeServers keeps every unknown key as an extra.
• Verified on 2026-10-31 with a scratch project:
  • Importing a .mimocode/mimocode.jsonc server that has sampling and alwaysDirectTools writes both keys into the shared mcpServers entry in .rulesync/mcp.json.
  • Running rulesync generate --targets mimocode --features mcp on that file writes only timeout, type, command and enabled.
  • Both keys disappear, and no warning is printed.
• Support level: project and global, both affected.

Minor (docs): source @see links point to the old package path

• Every @see in src/features/*/mimocode-*.ts points to https://github.com/XiaomiMiMo/MiMo-Code/blob/main/packages/opencode/.... For example, .../packages/opencode/src/config/mcp.ts now returns 404, because feat(deepagents): migrate hooks to the Hooks v2 document format #2591 moved the package to packages/cli.

Note (no change proposed yet): MiMo Desktop ignores project MCP config

• #2737 (spec) makes the Desktop Node engine drop MCP, LSP and formatter sections from any source outside MIMOCODE_CONFIG_DIR or the host-provided config. The Bun CLI is unchanged unless MIMOCODE_ONLY_CONFIG_DIR_PLUGINS is set.
• A project .mimocode/mimocode.jsonc MCP block that rulesync writes therefore has no effect in MiMo Desktop once this ships. A docs note may be enough.

Proposed Follow-up

• Give MimocodeMcp its own passthrough list for generate: OpenCode's fields plus sampling (an opaque object) and alwaysDirectTools (an array of strings). Copy them verbatim on generate, as timeout and oauth are copied today.
  • Because import puts them into the shared mcpServers, either keep them there (other targets ignore unknown keys) or move them into a mimocode-scoped block. Decide this in the PR.
• Update the @see links in the mimocode-* sources from packages/opencode/ to packages/cli/.
• Optional: add one sentence to the MiMo Code section of docs/reference/file-formats.md saying that MiMo Desktop ignores project MCP once JsonLogger drops warnings, so --json runs never see security-relevant notices #2737 ships.

References

• https://github.com/XiaomiMiMo/MiMo-Code/releases/tag/v0.1.16
• https://github.com/XiaomiMiMo/MiMo-Code/blob/main/packages/cli/src/config/mcp.ts
• https://github.com/XiaomiMiMo/MiMo-Code/blob/v0.1.16/packages/cli/src/config/mcp.ts
• XiaomiMiMo/MiMo-Code@014c3635
• feat(mcp): drive always-direct MCP tools from config XiaomiMiMo/MiMo-Code#2734
• https://github.com/XiaomiMiMo/MiMo-Code/blob/main/docs/compose/spec/always-direct-mcp-tools.md
• fix(config): restrict project execution without losing persisted settings XiaomiMiMo/MiMo-Code#2737
• https://github.com/XiaomiMiMo/MiMo-Code/blob/main/docs/compose/spec/project-config-execution.md
• chore(repo): rename packages/opencode to packages/cli XiaomiMiMo/MiMo-Code#2591
• Propose a MiMo Code target: .mimocode/ tree (mimocode.jsonc mcp/permissions, commands, agents, skills, plugins) #3173