Summary

I can create Railway projects/services via GraphQL, but linking a GitHub repo to a service via API fails with HTTP 400 “Problem processing request.” Reinstalling the Railway GitHub App with All‑repos

access did not help. Manual UI linking works. This blocks automation (batch of ~60 repos).

Environment

- API: https://backboard.railway.app/graphql/v2

- Token: RAILWAY_TOKEN (works for create project/service/env vars)

- Repo: https://github.com/teebuphilip/wynwood-thoroughbreds

IDs

- Project: b36c4e39-69ad-4129-b769-c1b4aaa9cc6b

- Service: f3416211-37bd-4d95-ace9-ae50404c45ee

Trace IDs

8991915530575196440, 6730767131461453434, 4136615408881108916, 2526255072095093210

Mutations tried (both fail with HTTP 400)

mutation ServiceUpdate($id: String!, $input: ServiceUpdateInput!) {

serviceUpdate(id: $id, input: { source: { repo: "https://github.com/teebuphilip/wynwood-thoroughbreds" } }) { id }

}

mutation ServiceUpdate($id: String!, $input: ServiceUpdateInput!) {

serviceUpdate(id: $id, input: { repo: "https://github.com/teebuphilip/wynwood-thoroughbreds" }) { id }

}

Response

{"errors":[{"message":"Problem processing request","traceId":"..."}]}

Schema errors when checking link status

- Cannot query field "source" on type "Service"

- Cannot query field "repo" on type "Service"

Request

Please confirm the correct GraphQL mutation and schema fields for linking a GitHub repo to a service. If additional fields are required (installation ID, repo ID, owner, etc.), please document/provide

them.

I can provide the full /tmp/railway_debug.log or the script if needed.