Promote Pi and OpenCode from preview to core harness tier — with live release evidence, then docs #21

Problem

A docs-vs-code congruence review (2026-09-14) found that OpenCode, pi and Grok Build are not confirmed as production-supported. The code agrees and is honest about it:

• packages/studyloop/src/studyloop/harnesses.py:23-25 — CORE_HARNESSES = ("kiro", "codex", "claude"), PREVIEW_HARNESSES = ("opencode", "pi", "grok"); the Harness(...) records for opencode/pi/grok carry production=False (lines 40–44).
• docs/agent-install.md:13 — "complete integrations for OpenCode, pi, and Grok Build … shown as preview harnesses until their live release checks pass on the target environment."

The owner's target state is five core harnesses — Kiro CLI, Claude Code, Codex, Pi and OpenCode — fully wired in and documented as such. Grok Build stays preview until separately evidenced.

What "fully wired in" must mean (checkable, per harness)

For each of pi and opencode, produce the same evidence the three core harnesses already have:

1. Install path — studyloop install agents --tool <h> writes the persona/agent definition and registers both MCP servers (session-db, studyloop) in the harness's own config schema; studyloop doctor reports the harness healthy.
2. Session launch — studyloop study --agent <h> (PTY) and, where the harness supports it, the ACP path start a session, deliver the canonical persona, and the one-session authority / reconnect / cleanup behaviour matches the core three (tests/test_web_session_start_pty.py, ..._acp.py parity).
3. Session export — the harness's transcript exporter lands rows in sessions.db with the correct source (pi, opencode), and session-export --<h>-only works (agent_session_tools exporters + tests).
4. Live release check — the harness-matrix live lane (tests/acceptance/, wave 2a B2) passes for the harness on a real install, and the receipt is committed under docs/architecture/plan-integration/receipts/ or the acceptance evidence bundle (wave 2b B4).
5. Study-plan-architect mode — studyloop study --mode plan-architect --agent <h> resolves the persona (OpenCode already has a global study-plan-architect agent; confirm pi).

Then, and only then

• Move pi and opencode into CORE_HARNESSES; set production=True; RELEASE_HARNESSES unchanged.
• Update docs/agent-install.md §"Supported in the initial pre-release" (five core; Grok Build remains preview), the capability matrix, AGENTS.md's harness sentence, the installer's printed language, and openspec/specs/agent-adapters/spec.md + harness-session-memory/spec.md.
• Pin with a test that the documented core list equals CORE_HARNESSES (there is a docs-contract test pattern in packages/agent-session-tools/tests/test_docs_semantic_layer_contract.py to copy).

Definition of done

• For pi and opencode: items 1–5 above each have a passing test id or a committed receipt named in this issue.
• harnesses.py core tuple = ("kiro", "codex", "claude", "pi", "opencode"); grok remains preview.
• Docs/spec/installer language updated in the same change; a contract test pins docs ↔ code.
• Full suite green; just lint; just typecheck.
• Council review (GPT Astra, Grok 4.6, + one best-for-purpose seat) of the evidence before the tier flip is merged.

Notes

• Do not flip the tier first and "fix docs later" — the preview label is currently the honest state, and the congruence review's finding was precisely that docs must not outrun evidence.
• Blocked by nothing; independent of the plan-integration programme (Integrate Study Plans across Now, Web architect, and MCP #7–Plan integration 8: Reconcile release contract and verify #15, PR Plan integration: PlanApplication seam, Bugs A/B closed (Phases 0–1) [in progress] #20). Can run in parallel.

Re-scope 2026-09-20 (milestone 0.5.x) — the original text above is kept as written

State on main (a03fc9bd): CORE_HARNESSES = ("kiro", "codex", "claude", "pi"), PREVIEW_HARNESSES = ("opencode", "grok") (harnesses.py:27-28). pi's items 1–5 are evidenced in docs/architecture/plan-integration/receipts/harness-evidence-2026-09-16.md; the promotion merged with the council's two conditions recorded as a checklist and not yet discharged. OpenCode's items 3 and 4 fail live. Grok stays preview and is out of this issue's scope (open a separate ticket if the transport-parity constraint changes).

What remains — each box is a single, checkable piece of work:

pi (already core; conditions from the 2026-09-16 harness-tier council)

• Replace the PaneDriver "prompt echo counts as a reply" heuristic with a programmatic completed-reply assertion in the acceptance lane, with a test that fails on an echo-only pane (packages/studyloop/tests/acceptance/).
• Re-run just testacc pi with STUDYLOOP_ACC_REAL_AUTH=1 on pi 0.73.1 (the mise/npm build; Homebrew's 0.65.0 is what pi resolves to today) and commit the run's evidence bundle under the receipt directory.

OpenCode (preview → core)

• OpenCodeExporter reads ~/.local/share/opencode/opencode.db (SQLite session/message/part), pinned by a live-schema test, not another fixture; session-export --opencode-only lands source='opencode' rows from a real install.
• One live acceptance run with a completed model reply (a provider with quota), evidence bundle committed.
• Then, and only then: CORE_HARNESSES gains "opencode", production=True, docs/spec/installer language in the same change, tests/test_docs_harness_tier_contract.py extended to pin it; council review of the evidence before the flip merges (per the DoD above).

Definition of done for this issue: all five boxes ticked, or the OpenCode boxes moved to their own issue with this one closed on pi's two. Not part of the 0.5.0 line — 0.5.0 ships the tiers exactly as main states them today.

_Milestone renamed 0.6.0 → 0.5.x on 2026-09-21 (owner rule): follow-on work ships as 0.5.N patch releases until every issue outstanding at v0.5.0 is resolved. Where the linked receipt says "0.6.0", read "the follow-on milestone"._