Project routing

A project either routes via your organization’s default policy or carries its own project-scoped routing policy. The policy uses the same shape as Embedded Routing Stack policies: PRIORITY tries a ranked list in order, INTELLIGENT picks per request from an allowed set. The two field sets are mutually exclusive by strategy.

Two fields on the project control this:

Supplying routing_policy together with uses_organization_default_routing: true is rejected with 422, as is false without a policy.

Create a project with its own routing

$
curl -X POST https://api-gateway.merge.dev/v1/projects \
>
  -H "Authorization: Bearer mgmt_<your_management_key>" \
>
  -H "Content-Type: application/json" \
>
  -d '{
>
    "name": "Field Mappings",
>
    "uses_organization_default_routing": false,
>
    "routing_policy": {
>
      "strategy": "PRIORITY",
>
      "priority_order": [
>
        { "model": "openai/gpt-5.5", "priority": 1 },
>
        { "model": "anthropic/claude-opus-4-8", "priority": 2 }
>
      ]
>
    }
>
  }'

For INTELLIGENT, allowed_providers is derived from allowed_models; if you supply it, it must match.

Replace the policy

routing_policy on PATCH is a full replacement, applied in place: the policy id is stable across updates, so IaC diffs stay clean. Sending a policy to a project that routes via the org default creates the scoped policy.

$
curl -X PATCH https://api-gateway.merge.dev/v1/projects/{project_id} \
>
  -H "Authorization: Bearer mgmt_<your_management_key>" \
>
  -H "Content-Type: application/json" \
>
  -d '{
>
    "routing_policy": {
>
      "strategy": "INTELLIGENT",
>
      "allowed_models": ["openai/gpt-5.5", "anthropic/claude-opus-4-8"]
>
    }
>
  }'

Back to org default routing

Send uses_organization_default_routing: true to delete the scoped policy and fall back to the org default. The response returns routing_policy: null.

$
curl -X PATCH https://api-gateway.merge.dev/v1/projects/{project_id} \
>
  -H "Authorization: Bearer mgmt_<your_management_key>" \
>
  -H "Content-Type: application/json" \
>
  -d '{ "uses_organization_default_routing": true }'