OpenRouter → MC-1

What changes

Keep the existing client behavior stable first. Introduce the MC-1 base URL, logical model, and server-side credential, then add control-plane constraints only after compatibility passes.

Feature mapping

• Change the OpenAI-compatible base URL and server-side key.
• Translate provider preferences into MC-1 provider controls only where supported.
• Compare model catalog, attribution, usage, and fallback semantics.

Migration sequence

• Inventory endpoints, models, streaming, tools, retries, and error handling.
• Create a scoped MC-1 project and test key.
• Run an owned non-production fixture through both paths.
• Compare outputs, tool continuation, latency, usage, and failures.
• Canary a reversible workload before broader promotion.

Compatibility example

export MC1_API_KEY="..."
export MC1_BASE_URL="https://api.colomboai.com/v1"
# Keep the client OpenAI-compatible and use model colomboai/mc-1.

Source-specific caveats

• OpenRouter routing/provider syntax is not assumed to be MC-1 policy.
• Verify every model-provider pair is configured and eligible in the target project.

Rollback

• Retain the previous route until acceptance passes.
• Do not translate unsupported provider-specific features silently.
• Record the exact client and integration versions used for validation.