feat(provider): add Command Code (commandcode.ai) as a first-class provider

Summary

Request to add Command Code (Provider API / GOAT & Pro Plans) as a first-class provider in OpenClaude.

Command Code provides unified access to 30+ top open-source and closed-source models (DeepSeek, GLM, MiniMax, Kimi, Claude, GPT, etc.) with prompt caching, usage-based metering, and standard OpenAI / Anthropic compatibility.

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Provider Technical Specifications

• Provider ID: commandcode
• Base URL: https://api.commandcode.ai/provider/v1
• Authentication:
  • Environment Variable: CMD_API_KEY (fallback: COMMANDCODE_API_KEY)
  • Header: Authorization: Bearer <CMD_API_KEY> (also supports x-api-key: <CMD_API_KEY> for Anthropic endpoint)
  • Security: Restrict via dedicatedCredentialsOnly: true to prevent generic OPENAI_API_KEY cross-contamination.
• Dual-Endpoint Contract:
  • OpenAI / Open-Source Models (e.g., deepseek/deepseek-v4-flash, moonshotai/kimi-k2.5):
    • Endpoint: POST https://api.commandcode.ai/provider/v1/chat/completions
    • Format: OpenAI Chat Completions schema (streaming supported with stream_options: {"include_usage": true}).
  • Anthropic Claude Models (e.g., claude-sonnet-5, claude-sonnet-4-6):
    • Endpoint: POST https://api.commandcode.ai/provider/v1/messages
    • Format: Native Anthropic Messages schema (usage emitted via message_delta).
  • Note: Command Code strictly returns 400 if Claude models are sent to /chat/completions or vice versa.
• Model Discovery:
  • Endpoint: GET https://api.commandcode.ai/provider/v1/models
  • Default Fallback Model: deepseek/deepseek-v4-flash
• Optional Headers:
  • x-cmd-zdr: 1 (Enforces zero data retention / no-training mode when enabled).

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Proposed Implementation

1. Descriptor (src/integrations/):
   • Register a commandcode gateway/vendor descriptor with CMD_API_KEY credential setup.
   • Configure model discovery pointing to https://api.commandcode.ai/provider/v1/models.
   • Implement route-level transport selection: route Claude model identifiers to the Anthropic Messages transport, and OpenAI/open-source models to the OpenAI-compatible shim.
2. Interactive Preset (/provider):
   • Add Command Code to the interactive /provider setup wizard.
   • Support startup auto-detection when CMD_API_KEY is present in the environment.
3. CLI & Profile Integration:
   • Support --provider commandcode and persistent provider profiles.

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Acceptance Criteria

• commandcode appears in /provider interactive setup and --provider commandcode CLI flag.
• Correct credential isolation (CMD_API_KEY is not leaked or overridden by generic OPENAI_API_KEY).
• Dynamic model catalog is fetched from https://api.commandcode.ai/provider/v1/models.
• OpenAI/open-source models route cleanly to /v1/chat/completions and Claude models to /v1/messages.
• Unit tests, lint, and typechecks pass.

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References

• Command Code Provider API: https://commandcode.ai/docs/provider
• Available Models Catalog: https://commandcode.ai/docs/reference/cli/models
• GOAT Plan: https://commandcode.ai/docs/plans/goat
• Zero Data Retention (ZDR): https://commandcode.ai/docs/resources/zdr