console: request-logs has no per-request billing source (go quota vs zen balance) #55643

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Describe the enhancement you want to request

Summary

The Console v2 request-logs API (GET /console/api/request-logs) returns one row per inference request, but rows carry no field telling whether the request was covered by the OpenCode Go plan quota or debited from the Zen balance. With "Use your balance after reaching the limits" enabled, Go-key requests that overflow the quota look identical to covered ones, so a precise month split of Go-covered traffic vs. balance spending cannot be built from the API.

Environment

• opencode version: 2.0.26 (client only; the gap is server-side, on the Console API)
• OS: Linux 6.12.107+deb13-amd64 (Debian 13, x86_64) — not relevant here; API-side report
• Terminal: tmux (TERM=tmux-256color, TERM_PROGRAM=tmux)
• Shell: /bin/bash
• Install/channel: latest (opencode --version → v2.0.26)
• Active plugins: none besides the custom global opencode-usage plugin, the client that reads this API to build monthly spend reports

Auth: Console session (auth / __Host-console_session cookies + x-org-id header), the same access pattern as the Console web app (#51806).

Reproduction

1. Workspace with an active Go subscription, a non-zero Zen balance, and "Use your balance after reaching the limits" enabled.
2. Keep sending requests through the Go key (/inference/go…) until the Go meters are spent, so later requests fall back to the balance.
3. Read the overflow period with GET /console/api/request-logs?category=inference&since=<ms>&until=<ms>&limit=20, then read GET /console/api/billing/ledger.

Expected Behavior

Either of these would let a client split the two buckets exactly:

1. request-logs rows expose a per-request billing source, e.g. billingSource: "go" | "balance" (the legacy /usage/rows shape carried a per-row billingSource, go / credit; the v2 endpoint dropped it), or
2. billing/ledger accepts since/until and a cursor, so balance debits can be listed for a whole month.

Actual Behavior

• Overflow rows still read product:"go" / path /inference/go… with a cost: nothing marks them as balance-charged, so they are indistinguishable from quota-covered rows.
• go/status meters (fiveHour / week / month, usedMicroCents / limitMicroCents / resetsAt) only say when coverage ran out; the month meter pins at its limit once spent and cannot say how much fell outside.
• billing/ledger has the exact data (one usage_debit per balance-charged request, amount matching the row cost) but returns only the last ~25 entries with no paging.

Additional Context

• Not an account support request: no account details are needed, and this is not a billing dispute. It is an API completeness request about data the backend already computes per request.
• Related history: [Console v2] /console/api/request-logs: 503 ServiceUnavailable above ~20-50 page size, /request-logs/export always 503 — and the legacy per-key /usage/rows endpoint is gone #51806 (the legacy /usage/rows endpoint, which carried per-row billing data, was retired in the Console v2 migration), Go endpoint bills Zen balance and triggers auto-reload after Go subscription ends #53364 (billing falls through to "balance" per request, i.e. the decision exists per request), opencode Go 'credits' won't be used, despite 'extra usage' is turned on #54783 (Go credits not used despite "extra usage").
• Consumers affected: third-party usage dashboards such as opencode-model-usage, opencode-limits and opencode-quota (all referenced in [Console v2] /console/api/request-logs: 503 ServiceUnavailable above ~20-50 page size, /request-logs/export always 503 — and the legacy per-key /usage/rows endpoint is gone #51806), plus custom reporting tools.
• Workarounds tried: replaying billing/ledger (too short), reading go/status meters (aggregate only), and mirroring request-logs locally (the ambiguity is mirrored).
• Reproducibility: consistent, observed on every Console v2 month.