feat: add built-in trae agent backed by trae-cli

[hqwuzhaoyi]

Summary

• add built-in agent id trae with command trae-cli acp serve
• document Trae CLI in built-in agent docs (README.md, agents/README.md)
• add agents/Trae.md
• update registry tests to include trae

Why

Today users must manually configure Trae CLI in ~/.acpx/config.json.
Making it built-in reduces setup friction and aligns with existing built-in agent UX.

Changes

• src/agent-registry.ts
  • add: trae: "trae-cli acp serve"
• README.md
  • built-in agents table adds Trae row
• agents/README.md
  • built-in list and docs index include Trae
• agents/Trae.md
  • new agent doc page
• test/agent-registry.test.ts
  • expected built-in list includes trae

Validation

• pnpm -s run build:test && node --test dist-test/test/agent-registry.test.js
• local runtime checks:
  • acpx --cwd /tmp --approve-all trae exec "Reply exactly: TRAE_ACPX_EXEC_TMP_OK"
  • session flow (sessions new / prompt / sessions history)
  • file write tool path test (TRAE_FILE_OK)
  • no-custom-config check:
    • remove agents.trae from ~/.acpx/config.json
    • run local packed build: npx --yes ./acpx-0.3.1.tgz --cwd /tmp --approve-all trae exec "Reply exactly: LOCAL_PUBLISH_TRAE_OK"

~/.acpx/config.json migration note

For users on this PR (or after release), agents.trae becomes optional.

Before:

{
  "agents": {
    "trae": { "command": "trae-cli acp serve" }
  }
}

After (optional cleanup):

{
  "agents": {
    "claude": { "command": "..." }
  }
}

If users want custom behavior, keeping an override is still supported:

{
  "agents": {
    "trae": { "command": "trae-cli acp serve" }
  }
}

Notes

• built-in agent id remains trae for compatibility
• underlying executable is trae-cli

[osolmaz]

Triage result

• Human attention: ⚠️ Required
• Recommendation: 🏁 escalate to a human
• Human decision needed: ready for human landing decision

Quick read

• The PR is right-shaped for the stated goal: add Trae as a built-in acpx agent instead of requiring manual config.
• Two minor follow-ups were handled in the autonomous lane: skills/acpx/SKILL.md was synchronized for the new harness-facing change, and the built-in command was corrected from trae-cli acp serve to traecli acp serve based on review evidence.
• Initial and final conflict checks are clean against origin/main.
• Targeted validation passed, and the current-head CI run finished green after workflow approval was applied.

Intent

Make Trae available out of the box as a built-in acpx agent so users can invoke trae without manual setup.

Why

acpx did not previously ship a built-in trae mapping or first-party Trae docs, so users had to add a custom agents.trae entry themselves. This change removes that setup friction and aligns Trae with the existing built-in agent UX.

Codex review

• GitHub Codex review data for the current head had no findings.
• The fresh local Codex review for the current head had no remaining blocking issues.
• One earlier P1 was resolved during the autonomous lane: the Trae built-in now uses the standard traecli executable, with matching code, docs, and a direct regression test update.
• The harness-facing skill docs were also synchronized by updating skills/acpx/SKILL.md.

CI/CD

• Targeted feature validation passed earlier with pnpm run build:test and node --test dist-test/test/agent-registry.test.js.
• The current-head CI run 23673804927 was initially approval-blocked (action_required), was approved, and then completed successfully on head e5f0930.
• There is one stale unrelated Actions entry: older run 23673659289 is still action_required for previous head 1efa5f6, not the current PR head.
• Final conflict gate is clean.

Recommendation

This is ready for a human landing decision. If you want trae to be a supported built-in harness in acpx, the branch is in good shape to merge.

[osolmaz]

Landed via temp rebase onto main.\n\n- Gate: validation completed for this repo's change scope\n- Land commit: 9680ced\n- Merge commit: 1acda08\n\nThanks @hqwuzhaoyi!