TokenMeter

LLM model metadata catalog and cost calculator for .NET.

Provides context windows, pricing, capability flags (vision, audio, reasoning, tool calling, prompt caching), and thinking/reasoning format metadata for 12+ providers including OpenAI, Anthropic, Google, xAI, Mistral, DeepSeek, and more.

Packages

Package	Description
TokenMeter	Full model catalog + cost calculation

Installation

dotnet add package TokenMeter

Quick Start

Model Lookup

// Find a model by ID or alias
var model = ModelCatalog.FindModel("claude-sonnet-4-6");

Console.WriteLine(model?.ContextWindow);          // 1000000
Console.WriteLine(model?.ReasoningMode);           // Optional
Console.WriteLine(model?.ThinkingFormat);          // Block
Console.WriteLine(model?.PromptCachingMode);       // Explicit
Console.WriteLine(model?.ToolCallingFormat);       // Anthropic
Console.WriteLine(model?.SupportsMcpToolUse);      // True

Note — fuzzy matching: FindModel resolves aliases in 4 passes (exact → alias exact → prefix → contains) to absorb cloud-specific ID variants (Bedrock/Vertex prefixes, date suffixes). Local/self-hosted deployment names that embed a public model name (e.g. deepseek-r1-distill-qwen-7b) can therefore match a catalog entry whose context window and pricing do not describe your deployment. For self-hosted models, take the effective context length from your deployment configuration (e.g. llama.cpp n_ctx), not from the catalog.

// When correctness matters more than recall, bound the fuzziness:
ModelCatalog.FindModel("deepseek-r1-distill-qwen-7b", AliasMatchType.Exact);   // null — no false positive
ModelCatalog.FindModel("us.anthropic.claude-sonnet-4.6-v1");                   // matched via contains alias

// Or inspect which pass produced the match and apply confidence-based fallback:
var match = ModelCatalog.FindModelMatch("deepseek-r1-distill-qwen-7b");
Console.WriteLine(match?.MatchKind);   // Prefix — a fuzzy inference, not an exact hit
Console.WriteLine(match?.Model.ModelId);

Cost Calculation

// Basic cost (input + output tokens)
var cost = model?.CalculateCost(inputTokens: 500_000, outputTokens: 200_000);

// Cost including prompt cache tokens
var costWithCache = model?.CalculateCost(
    inputTokens: 100_000,
    outputTokens: 50_000,
    cacheReadTokens: 400_000,
    cacheWriteTokens: 50_000);

// Via CostCalculator (DI-friendly)
ICostCalculator calc = CostCalculator.Default();
var price = calc.CalculateCost("gpt-4o", inputTokens: 1_000, outputTokens: 500);

Browsing the Catalog

// By provider — typed convenience property
foreach (var m in ModelCatalog.Anthropic.Values)
    Console.WriteLine($"{m.ModelId}: ctx={m.ContextWindow}, ${m.InputPricePerMillion}/M");

// By provider — string-keyed (when the name is only known at runtime)
var openai = ModelCatalog.GetProvider("OpenAI");   // dict, empty if unknown

// By model type (the built-in catalog currently contains Chat models only)
var chatModels = ModelCatalog.GetByType(ModelType.Chat);

// All providers
var providers = ModelCatalog.GetProviderNames();

Custom Models

var calc = CostCalculator.Default();
calc.RegisterModel(new ModelInfo
{
    ModelId = "my-fine-tuned-model",
    Provider = "MyCompany",
    InputPricePerMillion = 2.00m,
    OutputPricePerMillion = 8.00m,
    ContextWindow = 128_000,
    SupportsToolCalling = true,
    ToolCallingFormat = ToolCallingFormat.OpenAI
});

var cost = calc.CalculateCost("my-fine-tuned-model", 10_000, 5_000);

Model Metadata

ModelInfo provides the following metadata:

Identity

Property	Type	Description
ModelId	string	Canonical model identifier for API calls
Provider	string?	Provider name (e.g., "OpenAI", "Anthropic")
DisplayName	string?	Human-readable name
ModelType	ModelType	Chat, Embedding, Reranker, ImageGeneration, TextToSpeech, SpeechToText
IsInstructTuned	bool	Instruction-tuned vs. base model

Limits

Property	Type	Description
ContextWindow	int?	Maximum input tokens
MaxOutputTokens	int?	Maximum generated tokens per response

Pricing (USD / 1M tokens)

Property	Description
InputPricePerMillion	Standard input token price
OutputPricePerMillion	Standard output token price
CacheReadPricePerMillion	Prompt cache hit price (often 90% discount)
CacheWritePricePerMillion	Prompt cache population price
ImageInputPrice	Per-image input cost
AudioInputPricePerSecond	Audio input cost per second

Input Modalities

Property	Description
SupportsImageInput	Accepts image data
SupportsAudioInput	Accepts audio data
SupportsVideoInput	Accepts video data
SupportsDocumentInput	Accepts PDF/document files natively

API Capabilities

Property	Description
SupportsToolCalling	Tool/function calling
SupportsParallelToolCalling	Multiple tools per turn
SupportsStructuredOutput	JSON Schema-enforced output
SupportsJsonMode	JSON-guided output (soft)
SupportsStreaming	SSE streaming
PromptCachingMode	None / Explicit / Automatic
SupportsMcpToolUse	Native MCP tool support

Reasoning & Thinking

Property	Description
ReasoningMode	None / Optional / Always
ThinkingFormat	None / Block / InlineTag / SeparateField
ThinkingTagPattern	Tag pattern (e.g., <think>...</think>) for InlineTag format
ThinkingFieldName	Field name (e.g., reasoning_content) for SeparateField format
SupportsInterleavedThinking	Reasoning between tool calls
MaxThinkingTokens	Maximum reasoning budget

Tool Calling Wire Format

Value	Description
ToolCallingFormat.OpenAI	tool_calls / tool role (default)
ToolCallingFormat.Anthropic	tool_use / tool_result content blocks
ToolCallingFormat.Gemini	Google Gemini format

Supported Providers

Provider	Models
OpenAI	GPT-5.x, GPT-4.1, GPT-4o, o1, o3, o4-mini series
Anthropic	Claude 5, 4.x, 3.x families (Fable, Opus, Sonnet, Haiku)
Google	Gemini 3.x, 2.5, 2.0, 1.5 families
xAI	Grok 4.x, 3.x series
Azure	Azure OpenAI equivalents
Mistral	Large, Medium, Small, Magistral, Pixtral
DeepSeek	R1 (reasoning), V3, Coder
Amazon Nova	Premier, Pro, Lite, Micro
Cohere	Command A, R+, R, R7B
Meta Llama	Maverick, Scout
Perplexity	Sonar Pro, Deep Research, Reasoning
Qwen	Max, Plus, Turbo

Data Freshness

Console.WriteLine(ModelCatalog.LastUpdated);        // 2026-07-06
Console.WriteLine(ModelCatalog.DataAgeDays);        // days since last update
Console.WriteLine(ModelCatalog.IsDataStale());      // true if > 90 days old

Migration from 0.3.x

The following APIs were removed in 0.4.0:

• TokenMeter.Abstractions package (removed entirely)
• ITokenCounter, TokenCounter — use your own tokenizer library
• IUsageTracker, UsageTracker, UsageRecord, UsageStatistics — implement in your application
• ModelPricing → replaced by ModelInfo
• ModelPricingData → replaced by ModelCatalog
• ICostCalculator.GetPricing() → GetModel()
• ICostCalculator.RegisterPricing() → RegisterModel()

Requirements

• .NET 10.0 or later

License

MIT