Related Documentation: The Model Catalog powers Bifrost’s intelligent
routing system. See Provider Routing for
detailed examples of how governance and load balancing use the catalog to make
routing decisions, including cross-provider scenarios and weighted routing via
proxy providers.
Core Features
1. Automatic Pricing Synchronization
The Model Catalog manages pricing data through a two-phase approach: Startup Behavior:- With ConfigStore: Downloads a pricing sheet from Maxim’s datasheet, persists it to the config store, and then loads it into memory for fast lookups.
- Without ConfigStore: Downloads the pricing sheet directly into memory on every startup.
- When ConfigStore is available, an automatic sync occurs every 24 hours to keep pricing data current.
- All pricing data is cached in memory for O(1) lookup performance during cost calculations.
2. Multi-Modal Cost Calculation
It supports diverse pricing models across different AI operation types:- Text Operations: Token-based pricing for chat completions, text completions, responses, and embeddings. Cache-read/cache-write pricing applies to chat/text/responses when providers surface prompt cache token details.
- Audio Processing: Character-based, token-based, and duration-based pricing for speech synthesis and transcription, with audio token detail breakdown. Speech responses populate
usage.input_charsso speech can be billed by input characters in addition to tokens/duration. - Image Processing: Per-image (
input_cost_per_image/output_cost_per_image), per-pixel (input_cost_per_pixel/output_cost_per_pixel), or token-based pricing with text/image token breakdown. - Video Processing: Token-based or duration-based pricing. Input can use prompt tokens or
input_cost_per_video_per_second; output can use completion tokens or fall back tooutput_cost_per_video_per_second/output_cost_per_second. - Reranking: Input/output token pricing with search query cost support.
- Prompt Caching: Separate rates for cache-read tokens (
cached_read_tokens) and cache-creation tokens (cached_write_tokens), both surfaced underprompt_tokens_details(see Prompt Cache Cost Calculation).
3. Model Information Management
The Model Catalog maintains a pool of available models for each provider, populated from both pricing data and provider list models APIs. This enables:- Model Discovery: Listing all available models for a given provider
- Provider Discovery: Finding all providers that support a specific model with intelligent cross-provider resolution (OpenRouter, Vertex, Groq, Bedrock)
- Model Validation: Checking if a model is allowed for a provider based on allowed models lists (supports provider-prefixed entries)
4. Intelligent Cache Cost Handling
It integrates with semantic caching to provide accurate cost calculations:- Cache Hits: Zero cost for direct cache hits, and embedding cost only for semantic matches.
- Cache Misses: Combined cost of the base model usage plus the embedding generation cost for cache storage.
5. Tiered Pricing Support
The system automatically applies different pricing rates for high-token contexts, reflecting real provider pricing models. Two tiers are supported: above 128k tokens and above 200k tokens, with the higher tier taking precedence when both are configured.Configuration
TheModelCatalog can be configured during initialization by passing a Config struct.
PricingURL: Overrides the default URL (https://getbifrost.ai/datasheet) for downloading the pricing sheet.PricingSyncInterval: Customizes the interval for periodic pricing data synchronization. The default is 24 hours.
ModelCatalog:
Architecture
ModelCatalog
TheModelCatalog is the central component that handles all model and pricing operations:
Pricing Data Structure
Each model’s pricing information includes comprehensive cost metrics, supporting various modalities and tiered pricing:Usage in Plugins
The Model Catalog is designed to be shared across all Bifrost plugins, providing consistent model information and validation logic for governance, load balancing, and other routing mechanisms.Governance & Load Balancing: Both plugins delegate model validation to the
Model Catalog’s
IsModelAllowedForProvider method, ensuring consistent
handling of cross-provider scenarios and provider-prefixed allowed models. See
Provider Routing for configuration examples.Initialization
In Bifrost’s gateway, theModelCatalog is initialized once at the start and shared across all plugins:
Basic Cost Calculation
Calculate costs from a Bifrost response:Unified Cost Calculation
CalculateCost is the single entry point for all cost calculations. It handles all request types, semantic cache billing, and tiered pricing automatically:
Model Discovery
TheModelCatalog provides several methods to query for model and provider information.
Get Models for a Provider
Retrieve a list of all models supported by a specific provider.Get Providers for a Model
Find all providers that offer a specific model, including cross-provider resolution.- Direct Match: Checks each provider’s model list in
modelPoolfor the exact model name - OpenRouter Format: For models found in other providers, checks if
provider/modelexists in OpenRouter- Example:
claude-3-5-sonnetfound in Anthropic → checks OpenRouter foranthropic/claude-3-5-sonnet
- Example:
- Vertex Format: Similar check for Vertex with
provider/modelformat - Groq OpenAI Compatibility: For GPT models, checks if
openai/modelexists in Groq’s catalog - Bedrock Claude Models: For Claude models, flexible matching against Bedrock’s full ARN format
This cross-provider logic powers Bifrost’s intelligent routing capabilities.
See Provider Routing for
detailed examples of how this enables features like weighted routing via proxy
providers.
Check Model Allowance for Provider
Validate if a model is allowed for a specific provider based on an allowed models list. This method is used internally by governance and load balancing plugins.["*"]wildcard: Delegates toGetProvidersForModel(includes cross-provider logic) - this is the “allow all via catalog” mode- Non-empty explicit list: Checks for both direct matches and provider-prefixed entries
- Empty slice (
[]string{}/ emptyschemas.WhiteList): Returnsfalse(deny-all) - mirrors the config deny-by-default semantics
In
config.json and the governance API, allowed_models: [] (empty array)
means deny all models (deny-by-default, v1.5.0+). The Go helper
IsModelAllowedForProvider behaves the same way: an empty allowedModels
slice also returns false. Use ["*"] to allow all models validated through
the catalog.- Direct:
"gpt-4o"matches"gpt-4o" - Prefixed:
"openai/gpt-4o"matches request for"gpt-4o"(prefix stripped)
- Governance Routing: Validate if a model request is allowed for a provider configuration
- Load Balancing: Filter providers based on allowed models before performance scoring
- Virtual Key Validation: Check if a model can be used with a specific virtual key’s provider configs
Dynamically Add Models
You can dynamically add models to the catalog’s pool from av1/models compatible response structure. This is useful for providers that expose a model list endpoint.
- After fetching models from a provider’s
/v1/modelsendpoint - When a new provider is dynamically added at runtime
- For testing with custom model lists
Reloading Configuration
You can reload the pricing configuration at runtime if you need to change the pricing URL or sync interval.Error Handling and Fallbacks
The Model Catalog handles missing pricing data gracefully with intelligent fallbacks:Cleanup and Lifecycle Management
Properly clean up resources when shutting down:Thread Safety
AllModelCatalog operations are thread-safe, making it suitable for concurrent usage across multiple plugins and goroutines. The internal pricing data cache uses read-write mutexes for optimal performance during frequent lookups.
Best Practices
- Shared Instance: Use a single
ModelCataloginstance across all plugins to avoid redundant data synchronization. - Error Handling: Always handle the case where pricing returns 0.0 due to missing model data.
- Logging: Monitor pricing sync failures and missing model warnings in production.
- Cache Awareness: Use
CalculateCostwhich automatically handles cache hits/misses and embedding costs. - Resource Cleanup: Always call
Cleanup()during application shutdown to prevent resource leaks.

