Coding Plan API Providers (Z.AI, Moonshot, MiniMax)

[davidste]

Summary

Add coding-plan API provider support for:

• Z.AI coding plans
• Moonshot/Kimi coding APIs
• MiniMax coding APIs

This issue covers API-key compatible coding-plan integrations (not OAuth subscription adapters).

Depends On

• #103 — Subscription-Backed Model Support (Umbrella)

Why This Issue Exists

• Loomkin currently includes zai paths but coding-plan provider coverage is incomplete.
• req_llm runtime in this repo does not currently expose Moonshot/MiniMax provider modules by default.
• Provider/model discovery and cost handling need explicit integration work for these providers.

Scope

Provider integration strategy

• Implement a verified strategy for Moonshot/MiniMax in Loomkin runtime:
  • register custom providers, or
  • adopt dependency update that exposes required providers.
• Keep strategy explicit in code/docs so rollout is deterministic.

Model routing + discovery

• Extend Loomkin model/provider discovery to surface supported coding-plan providers.
• Ensure users can select these providers from current model selection UX.
• Preserve compatibility with direct provider:model string entry.

Config

• Add submit-ready .loomkin.toml config support for coding-plan providers:
  • base URLs
  • API keys (env interpolation)
  • optional provider mode (OpenAI-compatible vs Anthropic-compatible where relevant)

Cost/budget behavior

• Define and implement pricing behavior for coding-plan providers:
  • explicit per-model pricing table where possible
  • deterministic fallback behavior when provider usage does not include total_cost
• Keep rate limiter/budget logic stable.

Out of Scope

• OAuth login/refresh/revoke lifecycle.
• Anthropic/Codex/Gemini subscription OAuth adapters.

Acceptance Criteria

• Z.AI coding-plan path is fully integrated and selectable.
• Moonshot coding-plan path is integrated with a verified runtime provider strategy.
• MiniMax coding-plan path is integrated with a verified runtime provider strategy.
• .loomkin.toml coding-plan config is implemented and validated.
• Cost and budget behavior for coding-plan usage is deterministic and tested.
• Integration tests cover model selection, provider call success, and invalid config/key cases.

Implementation Touchpoints

• lib/loomkin/models.ex
• lib/loomkin/config.ex
• lib/loomkin/teams/pricing.ex
• lib/loomkin/teams/cost_tracker.ex
• lib/loomkin/teams/agent.ex
• lib/loomkin_web/live/model_selector_component.ex
• mix.exs / mix.lock (if dependency strategy requires updates)

Related

• Umbrella: #103 — Subscription-Backed Model Support (Umbrella)
• Cost & Token Analytics Dashboard #68 (Cost & Token Analytics Dashboard)