Premium compound routing

Sage Router Fusion

Run multiple eligible models side by side, then synthesize consensus, contradictions, and the strongest final answer through one OpenAI-compatible response. Use sage-router/fusion or the compatible sage-router:fusion server tool.

No provider key or credit card required until your generated sk_sage key exists.

Fusion is available to Pro, Max, metered, manual, and operator-enabled customers. Lite/free generated keys receive 402 fusion_plan_required.

1

Send one request

Call the hosted edge with your generated sk_sage_* key and a high-stakes prompt that benefits from comparison, review, risk analysis, or research.

2

Run the panel

Sage Router selects a small panel of eligible, authorized routes from the active profile and skips routes that are unavailable or disallowed.

3

Judge the answers

A judge route compares panel outputs for agreement, gaps, contradictions, and useful details before producing the final answer.

4

Return one response

The result is a normal OpenAI-compatible chat completion with bounded Fusion metadata and no prompt or panel-answer logging in route events.

Direct model alias

Use Fusion as a premium model.

For new Sage Router clients, call sage-router/fusion. Sage Router returns the canonical Fusion response shape for premium synthesis requests.

curl "https://api.sagerouter.dev/v1/chat/completions" \
  -H "Authorization: Bearer sk_sage_..." \
  -H "Content-Type: application/json" \
  -d '{
    "model": "sage-router/fusion",
    "messages": [
      {"role": "user", "content": "Compare the safest launch options and recommend one."}
    ]
  }'

Server tool compatibility

Attach sage-router:fusion to agent requests.

gateway-style clients can request the Fusion server tool without forwarding unknown tool markers downstream. Set tool_choice to required when you want deterministic invocation.

{
  "model": "sage-router/frontier",
  "messages": [
    {"role": "user", "content": "Survey the strongest arguments for and against this launch."}
  ],
  "tools": [{"type": "sage-router:fusion"}],
  "tool_choice": "required"
}
Research

When one model may miss the angle.

Use Fusion for market scans, architecture reviews, launch sequencing, incident postmortems, and high-ambiguity analysis where a second or third perspective changes the answer quality.

Agents

When harnesses need one final answer.

Agents still receive one chat completion, while Sage Router performs the panel and judge work inside the route. Existing OpenAI-compatible clients do not need a new SDK.

Boundary

Only authorized routes participate.

Fusion does not grant unauthorized provider access, pool customer accounts, or bypass provider terms. It routes only through providers and local models the deployment is allowed to use.

Premium gate

Fusion is a Pro/Max conversion feature.

The route is designed as a paid synthesis budget, not a free unlimited model marketplace. Lite/free accounts get explicit upgrade guidance through fusion_plan_required.

  • Pro: daily high-stakes agent work with premium Fusion synthesis and frontier routing profiles.
  • Max: higher volume automation, priority fallback, and a larger Fusion budget for teams.
  • Local/private: self-hosted deployments can keep provider credentials on the router host or Tailnet while using the same model names and server-tool shape.
  • Telemetry: route events record status, elapsed time, selected route IDs, plan, and auth type, not prompts, panel answers, final answers, API keys, OAuth tokens, or provider credentials.