#7741 feat(agents): add GPT-6 and Opus 5.5 support

What & why

Add support for GPT-6 Sol, GPT-6 Luna, and Claude Opus 5.5.

• Add GPT-6 Sol and GPT-6 Luna to the Superset Chat and Codex workspace model selectors.
• Add Claude Opus 5.5 to the Superset Chat and Claude workspace model selectors.
• Pass the selected model ID to the corresponding CLI when spawning a workspace.
• Track API-equivalent input, output, cache-read, and cache-write costs for all three models.
• Expose the supported reasoning-effort levels for the new GPT-6 models.
• Verify the model IDs, capabilities, and pricing against the current OpenAI and Anthropic documentation.

How I tested it

• bun test packages/shared/src/agent-models.test.ts packages/host-service/src/trpc/router/usage/history/pricing.test.ts
  • 67 passed, 0 failed
• bun run lint
• bun run typecheck
  • 42 tasks passed
• Manually verified GPT-6 Sol and GPT-6 Luna in the Codex model dropdown.
• Manually verified Opus 5.5 in the Claude model dropdown.
• Manually verified GPT-6 Sol in Usage with an estimated cost.

Screenshots

Checklist

• PR title follows conventional commits (type(scope): subject)
• bun run lint and bun run typecheck pass
• Allow edits from maintainers

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Summary by cubic

Adds GPT-6 Sol, GPT-6 Luna, and Claude Opus 5.5 to the Superset Chat and agent model selectors.

• Passes the selected model ID to the Codex or Claude CLI when spawning a workspace.
• Tracks API-equivalent input, output, cache-read, and cache-write costs for all three models.
• Exposes the supported reasoning-effort levels for the GPT-6 models; Sol supports ultra, Luna tops out at max.
• Bumps the pricing table updated date to 2026-09-22.