Summary

• Adds a fast-check property suite for the model resolution pipeline in lib/request/helpers/model-map.ts — the parser every request's model routing flows through (resolveNormalizedModel → getModelProfile). The test: property-check the unsupported-model fallback invariants #574 suite property-checked the unsupported-model fallback chain; this one pins the resolution layer beneath it.

What Changed

New test/property/model-map.property.test.ts (6 properties). Inputs mix known MODEL_MAP aliases, synthesized GPT-5 spellings (minors 0–9, mini/nano/pro/codex variants, -/./space separators, version suffixes), provider prefixes (openai/, models/, nested), random per-character casing, and raw garbage strings:

1. Closed world — every resolution lands on a MODEL_PROFILES key, proving getModelProfile's DEFAULT_MODEL fallback is pure defence (no reachable input needs it; a MODEL_MAP value or catalog entry without a profile would be found instantly).
2. Idempotence — normalized outputs are fixpoints of the resolver.
3. Spelling invariance — provider prefixes and arbitrary casing never change the resolution, for any input including garbage.
4. Codex dominance — unmapped ids mentioning codex resolve to CURRENT_CODEX_MODEL, never a general model.
5. The inverse — unmapped general GPT-5 spellings stay codex-free and in the gpt-5 family: a general-purpose request can never silently route to a codex-tuned model.
6. Alias fidelity — every explicit MODEL_MAP alias resolves to its mapped target under any prefix/casing spelling (sweeps the whole map every iteration, so a future alias edit that breaks case-insensitive lookup fails immediately).

No SUT bugs found.

Validation

• npm test -- test/property/model-map.property.test.ts test/model-map.test.ts — 21/21 (new 6 + existing 15 untouched)
• npm run typecheck (also via pre-commit hook)
• npx eslint test/property/model-map.property.test.ts --max-warnings=0

Docs and Governance Checklist

• Test-only; no behavior or docs surface changed

Risk and Rollback

• Risk level: minimal — additive test file; conventions match the existing test/property/ suites.
• Rollback plan: revert the single commit.

https://claude.ai/code/session_01XNtnkLbBiXZxfQQYLMpucB

Generated by Claude Code

note: greptile review for oc-chatgpt-multi-auth. cite files like lib/foo.ts:123. confirm regression tests + windows concurrency/token redaction coverage.

Greptile Summary

adds test/property/model-map.property.test.ts — a six-property fast-check suite that pins the resolution layer of resolveNormalizedModel / getModelProfile (the path every request's model routing flows through). no sut or production code is changed.

• closed-world + idempotence (props 1–2): every input, including garbage, lands on a MODEL_PROFILES key, and normalized outputs are fixpoints of the resolver.
• spelling invariance (prop 3): three independent assertions — prefix-only, casing-only, and combined prefix+casing — confirm stripProviderPrefix + case-fold runs safely as one path for synthesized, mapped, and garbage inputs.
• codex/general separation (props 4–5) and alias fidelity (prop 6): unmapped codex ids always route to CURRENT_CODEX_MODEL; general GPT-5 spellings never silently route to a codex-tuned model; every MODEL_MAP alias resolves to its declared target under any prefix or casing.

Confidence Score: 5/5

test-only addition with no production code changes; safe to merge

single additive test file; all six properties are logically sound against the sut — every resolveNormalizedModel exit path returns a MODEL_PROFILES key, all catalog outputs are self-aliases in MODEL_MAP ensuring idempotence holds, and the combined prefix+casing assertion in property 3 closes the gap flagged in the previous review thread

no files require special attention

Important Files Changed

Flowchart

%%{init: {'theme': 'neutral'}}%%
flowchart TD
    IN["arbModelId\n(MAP_KEY | synthesized GPT-5 | garbage)\n+ arbPrefix"] --> RNM["resolveNormalizedModel"]
    RNM --> SPP["stripProviderPrefix\n(take last '/' segment)"]
    SPP --> LMM{"lookupMappedModel\n(exact, then case-insensitive)"}
    LMM -->|hit| OUT1["MODEL_MAP value"]
    LMM -->|miss| RCC{"resolveCodexCatalogModel\nincludes('codex')?"}
    RCC -->|yes| OUT2["CURRENT_CODEX_MODEL"]
    RCC -->|no| RGC{"resolveGeneralGpt5CatalogModel\ntokenize to GPT-5 family?"}
    RGC -->|yes| OUT3["catalog entry"]
    RGC -->|no| OUT4["DEFAULT_MODEL (gpt-5.5)"]

_{Reviews (2): Last reviewed commit: "test: combine prefix and casing mutation..." | Re-trigger Greptile}