consult: change shipped default lane models to claude-opus-5 and gpt-5.6-sol

[waleedkadous]

Decision (owner-directed, 2026-07-29)

The repo owner has directed that the shipped defaults for consult lane models move forward — not just the config mechanism from #1286. Every adopter that hasn't configured consult.models should get these lanes by default:

Lane	Current shipped default	New shipped default
claude	claude-opus-4-6 (consult/index.ts:558)	claude-opus-5
codex	gpt-5.4 @ medium reasoning (consult/index.ts:417-419)	gpt-5.6-sol @ medium
gemini	agy default, no --model	unchanged

Live-probe evidence (both ids functionally verified — do not re-litigate from cached catalogs)

Per this repo's standing rule, model-id existence claims require a live probe, never a cached table:

• claude-opus-5 — probed 2026-07-28 via claude --model claude-opus-5; the model self-identifies. Confirmed.
• gpt-5.6-sol — probed 2026-07-29 via codex exec --model gpt-5.6-sol; returned a correct completion (11.7k tokens). Confirmed.
• gpt-5.6 (plain) and gpt-5.6-codex — both probed 2026-07-29 and REJECTED: The '<id>' model is not supported when using Codex with a ChatGPT account. The -sol suffix is load-bearing; do not "simplify" the id.

Scope (BUGFIX/AIR-sized)

1. Flip the two hardcoded ids in packages/codev/src/commands/consult/index.ts (claude lane claudeQuery model; codex lane startThread model). Keep codex reasoning effort at medium.
2. CODEX_PRICING (consult/index.ts:386) hardcodes gpt-5.4 per-1M rates. Update to gpt-5.6-sol's published rates, verified against OpenAI's current pricing page at implementation time. If published per-1M rates for this id cannot be verified, record cost_usd as null for the lane rather than computing from gpt-5.4 rates (matches consult: configurable per-lane models and per-review-type lane selection #1286's cost rule: a confidently wrong number is worse than none).
3. Docs: codev/resources/commands/consult.md + skeleton counterpart; the "Multi-Agent Consultation" section of CLAUDE.md/AGENTS.md names GPT-5.4 — update BOTH files identically, and mirror every framework change across codev/ and codev-skeleton/.
4. A smoke test or CI-safe unit assertion that the shipped defaults are the ids above (so a future drive-by "correction" of the unusual -sol id fails a test instead of silently landing).

Coordination with #1286 (in flight)

#1286 refactors these exact lines into config-driven resolution with the hardcoded values as fallback defaults. Whichever PR lands second rebases; the semantic is identical either way — these ids become the fallback when no consult.models config is present. If this issue lands first, #1286's "default preservation" test vectors must assert the NEW ids.

Out of scope

• Default lane composition (which lanes run) — unchanged.
• The gemini/agy lane's default model — unchanged.
• The consult: configurable per-lane models and per-review-type lane selection #1286 config mechanism itself.