Package com.tnsai.llm.observability

Class JsonLLMPricingRegistry

java.lang.Object

com.tnsai.llm.observability.JsonLLMPricingRegistry

All Implemented Interfaces:

LLMPricingRegistry

public final class JsonLLMPricingRegistry
extends Object
implements LLMPricingRegistry

LLMPricingRegistry that loads rates from a classpath JSON file (issue #79).

Default rate card ships at /pricing/2026-05.json bundled in this module. Consumers wanting enterprise-negotiated rates can ship their own JSON and call fromClasspath(String) with their resource path. The JSON shape is:

 {
   "version": "2026-05",
   "providers": {
     "openai": {
       "gpt-4o": {
         "prompt_per_1k": 0.0025,
         "cached_per_1k": 0.00125,
         "completion_per_1k": 0.01,
         "reasoning_per_1k": null
       },
       ...
     },
     "ollama": { "*": { ... } }
   }
 }
 

The "*" model key acts as a catch-all for that provider — useful for self-hosted providers (Ollama, vLLM) where every model has the same operational cost (zero, in the local case).

Internally delegates to InMemoryLLMPricingRegistry: the JSON loader is a thin parser that wires rates into the in-memory adapter.

Since:

0.9.0 (issue #79)

Field Summary

Fields

Modifier and Type	Field	Description
static final String	DEFAULT_RESOURCE	Default rate card shipped in this module.

Method Summary

Modifier and Type	Method	Description
static JsonLLMPricingRegistry	defaultRegistry()	Load the bundled default rate card (DEFAULT_RESOURCE).
CostEstimate	estimate(String provider, String model, TokenUsage usage)	Compute a USD cost estimate for the given usage under the named provider + model.
static JsonLLMPricingRegistry	fromClasspath(String resourcePath)	Load a rate card from a classpath resource.
String	tableVersion()	Stable version identifier of the pricing data — a date string, a content hash, whatever survives "what was the rate when this call was billed?"

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

DEFAULT_RESOURCE

public static final String DEFAULT_RESOURCE

Default rate card shipped in this module.

See Also:

• Constant Field Values

Method Details

defaultRegistry

public static JsonLLMPricingRegistry defaultRegistry()

Load the bundled default rate card (DEFAULT_RESOURCE).

fromClasspath

public static JsonLLMPricingRegistry fromClasspath(String resourcePath)

Load a rate card from a classpath resource.

Throws:

IllegalStateException - if the resource is missing or malformed

estimate

public CostEstimate estimate(String provider,
 String model,
 TokenUsage usage)

Description copied from interface: LLMPricingRegistry

Compute a USD cost estimate for the given usage under the named provider + model. Implementations MUST return a non-null CostEstimate; if the pair is unknown, return a zero estimate stamped with LLMPricingRegistry.tableVersion() so the caller still sees provenance.

Specified by:

estimate in interface LLMPricingRegistry

tableVersion

public String tableVersion()

Description copied from interface: LLMPricingRegistry

Stable version identifier of the pricing data — a date string, a content hash, whatever survives "what was the rate when this call was billed?" audits. Embedded in every CostEstimate the registry produces so downstream cost-aggregation can detect rate-table drift.

Specified by:

tableVersion in interface LLMPricingRegistry