Add a unified model_overrides config section that lets users manually
declare context_window, max_output_tokens, capabilities, cost, and
family for any provider+model — winning over models.dev, OpenRouter, and
hardcoded defaults.
Resolution order (first hit wins):
1. model_overrides.<provider>.<model_id> (per-provider+model)
2. model_overrides.<provider>._default (per-provider default)
3. model_overrides._default (global default)
4. Normal catalog resolution
Key subtlety: an unknown model id (not in the
catalog) derives base metadata from sensible defaults before patching,
so overriding a model the catalog doesn't know yet is the supported
self-unblock path. This is exactly the #84482 scenario (Upstage
solar-pro4/syn-pro wrong context) and the #8731 scenario (custom/local
models with manual capability declaration).
Wired into:
- get_model_capabilities() — patches capability fields; unknown models
get safe defaults (tools on, vision/reasoning off) before patching
- lookup_models_dev_context() — context_window override, checked before
catalog lookup so it works even for providers not in PROVIDER_TO_MODELS_DEV
- get_model_info() — merges override dict onto catalog entry (shallow
merge); for unknown models, the override is the sole source of metadata
- get_model_context_length() — step 0b in the resolution pipeline,
before custom_providers (0c) and before any network probe
Config example:
model_overrides:
upstage:
solar-pro4:
context_window: 524288
syn-pro:
context_window: 65536
custom:my-local-vllm:
my-llava-model:
context_window: 8192
supports_vision: true
supports_reasoning: false
supports_tools: true
_default:
context_window: 128000
Fixes#8731Fixes#84482
Refs #47247