Two blockers from the maintainer's Oracle review on PR #4121:
Blocker 1 — load_skills=null should still throw, omitted should default
The previous PR collapsed both `loadSkills === undefined` and
`loadSkills === null` into a silent default of `[]`. The closing
rationale of PR #1663 (which reverted PR #1493) and the maintainer's
review both call out the importance of preserving the distinct
"omitted -> default, explicit invalid -> throw" contract. `null`
strongly signals "I tried to pass something and it was wrong";
silently coercing it hides bugs upstream.
Restored the split: `undefined` -> default `[]` + log,
`null` -> throw with the historical error string.
Blocker 2 — task_id continuation test rewritten, not deleted
The original PR removed the `task_id without run_in_background ->
throws` test entirely. The behavior IS preserved (default false ->
`isExplicitSyncRun` true -> `executeSyncContinuation`), but with the
test gone the new contract was unprotected.
Added a regression test that asserts the new contract: when
`task_id` is present and `run_in_background` is omitted,
`tool.execute` must route through sync continuation without throwing
the legacy required-parameter error. Mocks include `session.abort`
because the sync poller calls it during shutdown.
Also flipped the existing `load_skills=null` regression test from
"normalizes to []" back to "throws with the legacy error string" to
match the restored contract.
Tests:
- bun test src/tools/delegate-task/tools.test.ts -> 132/132 pass
- bun test src/tools/delegate-task/ -> 406/406 pass
- bun run typecheck -> clean
Sisyphus and other delegators occasionally invoke the task() tool without
an explicit run_in_background or load_skills argument. The runtime
validators in tool-argument-preparation.ts threw a hard Error in that
case, which short-circuited tool.execute() entirely. Because OpenCode's
tool.execute.after hook only runs on returned results, the
delegate-task-retry hook never had a chance to attach corrective
guidance — so the model saw a raw failure and either burned several
retries or fell back to a synchronous Explore call, silently losing
parallel execution.
Behavior change:
- run_in_background omitted -> defaults to false (sync delegation), with
a log entry for observability.
- load_skills omitted or null -> normalized to [] with a log entry on
the explicit-null path.
- The Zod schema entries are now .optional() and their .describe()
strings declare the defaults honestly; the markdown tool description
was updated to match (no more 'REQUIRED' lie).
The orthogonal validation 'Must provide either category or
subagent_type.' is unchanged and still surfaces as a returned error.
Tests:
- The five throw-on-missing tests in tools.test.ts are rewritten to
assert the new default-and-proceed contract.
- The 'no category, no subagent_type' test now asserts the
missing-target error remains intact.
Refs the workaround the reporter validated in the original issue body;
matches the design from PR #2375 which was previously reverted by
566031f4.
Include Vertex Anthropic in the assistant-tail prefill guard after Cubic flagged the strict provider check. Keep the non-Anthropic opencode negative control covered by tests.
Plan: plans/fix-anthropic-assistant-prefill-tail.md
Tighten the assistant-tail repair after review so only the Anthropic provider is treated as prefill-rejecting, and so assistant-tail model metadata is evaluated independently from the last user model.
Add regression coverage for an allowed user model followed by a rejecting Anthropic assistant tail, plus a non-Anthropic provider carrying a Claude-looking model id.
Plan: plans/fix-anthropic-assistant-prefill-tail.md
Claude Opus 4.7 rejects requests whose final message is an assistant turn, because Anthropic treats that as unsupported assistant prefill. Add a transform guard that appends the existing synthetic user recovery turn only for Anthropic prefill-rejecting model IDs, while preserving assistant-prefill behavior for supported and unknown models.
Tests cover Opus 4.7, Opus 4.6 assistant metadata fallback, direct Sonnet 4.6 model fields, allowed OpenAI/Sonnet 4.5 tails, missing metadata, and compaction continuation compatibility.
Plan: plans/fix-anthropic-assistant-prefill-tail.md
- Add focused ROADMAP with TOC and clear priorities
- Pin package layering refactor as #1 urgent work
- Add multi-harness agent OS notice to all language READMEs
- Add ROADMAP section to root README with contributor guidance
- All ROADMAP-related PRs should use the ROADMAP label
Require the latest assistant tool-wait turn itself to be stale before a shouldReply parent wake can bypass tool-call deferral. This prevents an all-complete background wake from forking a second parent prompt loop when OpenCode has repaired the tail to a synthetic user message.
Tests:
- bun test src/features/background-agent/parent-wake-user-message-race.test.ts src/features/background-agent/task-completion-cleanup.test.ts src/hooks/shared/prompt-async-gate.test.ts src/shared/prompt-async-route-audit.test.ts --bail
- bun run typecheck
- bun test
Keep the built-in lsp MCP registered even when the submodule CLI artifact is missing.
The fallback command initializes the lsp-tools-mcp submodule, prefers the source CLI without dirtying the checkout with dist output, and keeps npm build as a last resort when Bun cannot run the source entrypoint.
Plan: plans/fix-lsp-mcp-missing-cli.md
When OpenCode reports the original assistant error after a fallback retry has already been accepted, keep waiting for the pending fallback model instead of clearing the awaiting flag.
This prevents a duplicate stale session.error from advancing the fallback chain and dispatching a second assistant retry prompt.
Claude Agent