[diegosouzapw]

Summary

• accept relative Claude message endpoints during request-format detection
• recognize kebab-case anthropic-version metadata as a Claude-format signal
• preserve the existing endpoint-first detection and absolute-URL behavior

Attribution

Thanks to @ervareza for the original implementation.

Changes

• make detectFormatFromUrl parse relative and absolute URLs safely
• add anthropic-version detection for array and string message content
• add focused regressions for Claude Code model-validation requests

Test plan

• focused + neighboring Node tests: 17 passed
• ESLint on changed files
• Prettier on changed files
• npm run typecheck:core
• npm run check:docs-all
• npm run check:cycles
• npm run typecheck:noimplicit:core — blocked by existing implicit-any errors in open-sse/utils/usageTracking.ts and src/shared/services/cliRuntime.ts
• npm run test:vitest — 28 files / 256 tests passed; 6 MCP suites cannot import js-tiktoken because the local base64-js installation is empty (the same failure reproduces in the release checkout)
• npm run check — lint completed; the broad unit run was interrupted after reproducing the same dependency-layout failure plus credential-dependent 401 checks

[diegosouzapw]

Merged via local merge-train on 192.168.0.113 (32 cores) @ train tip e3a7696bb969536578f6a2defeada7d04fa9d1f9 — log /srv/omniroute-train/.claude/worktrees/merge-train-20260804-120425-suite.log.

Green: typecheck:core, check-complexity, check-cognitive-complexity, check-changelog-integrity, test:vitest (34 files / 291 tests).

Reds, each discriminated against the clean release tip 2e4268003 with zero PRs boarded (merge-gates §3):

• check-file-size — src/sse/handlers/chat.ts 1846>1845 and open-sse/executors/base.ts 1623>1578 reproduce with identical numbers on the bare tip. Baseline drift for the release captain; not introduced here.
• test:unit — 15 failures, all reproduced identically on the bare tip. Thirteen are the bare-model routing assertions (OpenAI remains the historical default, getModelInfoCore keeps unprefixed gpt-5.5 on the OpenAI fallback, …) left stale by fix(routing): bare model ids route to codex first; validate synced candidates #9275, which intentionally moved bare gpt-5.5/gpt-5.6-sol to codex without updating them; two are the trailing-period message change already covered by test(sse): expect the trailing period in the no-credentials message #9392.
• provider-limits-local-apikey-sync-spacing — the only failure not on the bare tip, and a load flake: the assertion requires a ~0ms gap and measured 25/49ms under a 32-core full-suite run. Passes 3/3 in isolation on this exact train tip.

No red attributable to this PR.