Surface ModelBilling.tokenPrices on public SDK types

[MackinnonBuck]

Summary

ModelBilling.tokenPrices is present on the wire and in every SDK's generated protocol types, but the hand-curated public ModelBilling types exposed only multiplier. Consumers had to narrow through local augmentations to read tier pricing (e.g. to detect a distinct long-context tier and label tiers like 200K / 1M in a model picker).

This adds tokenPrices to the curated public ModelBilling across all SDKs, mirroring the shape already published in the generated schema.

Shape

• ModelBillingTokenPrices: inputPrice, outputPrice, cachePrice (numbers), batchSize, contextMax (ints), longContext
• ModelBillingTokenPricesLongContext: inputPrice, outputPrice, cachePrice (numbers), contextMax (int)

All fields optional; JSDoc/descriptions copied from the runtime schema.

Per-SDK changes

SDK	Change
Node	types.ts: curated interfaces + tokenPrices?; exported from index.ts
Python	client.py: dataclasses with from_dict/to_dict, wired into ModelBilling; exported in __init__.py
Go	types.go: structs + TokenPrices pointer field
.NET	Types.cs: sealed classes + property + [JsonSerializable] registrations
Java	new ModelBillingTokenPrices.java / ...LongContext.java + field on ModelBilling.java
Rust	types.rs: re-export the two nested generated types (generated ModelBilling already carries token_prices)

No generated files were modified — they already carry the field. No runtime changes required.

Tests

Added coverage exercising the new field in every SDK (round-trip (de)serialization for Python/Go/.NET, deserialization assertions for Java, type + passthrough for Node, and re-export verification for Rust). All passing.

[Copilot]

Pull request overview

This PR surfaces ModelBilling.tokenPrices on the curated, public-facing ModelBilling types across the SDKs (Node, Python, Go, .NET, Java, Rust), aligning the hand-authored public API with an already-present wire/generated schema field so consumers can read tiered token pricing (including long-context tier details).

Changes:

• Added public ModelBillingTokenPrices / ...LongContext types (or re-exports) and exposed tokenPrices on ModelBilling across SDKs.
• Updated per-language serialization/deserialization paths (where applicable) to carry tokenPrices.
• Added/expanded tests in each SDK to validate the new field is preserved through (de)serialization and public exports.

Show a summary per file

File	Description
rust/tests/session_test.rs	Extends model-list test payload and asserts access to re-exported token price types.
rust/src/types.rs	Re-exports generated ModelBillingTokenPrices* types via the public types module.
python/test_client.py	Adds round-trip tests for ModelBilling.tokenPrices and the nested long-context tier.
python/copilot/client.py	Introduces dataclasses + (de)serialization for tokenPrices and wires into ModelBilling.
python/copilot/init.py	Exports the new Python billing token price types at package level.
nodejs/test/client.test.ts	Adds billing.tokenPrices to test model payload and asserts deep access.
nodejs/src/types.ts	Adds curated public TS interfaces for ModelBillingTokenPrices* and ModelBilling.tokenPrices.
nodejs/src/index.ts	Exports the new TS public types from the package entrypoint.
java/src/test/java/com/github/copilot/MetadataApiTest.java	Extends deserialization test to assert token price fields and long-context tier parsing.
java/src/main/java/com/github/copilot/rpc/ModelBillingTokenPricesLongContext.java	Adds public RPC type for long-context tier pricing.
java/src/main/java/com/github/copilot/rpc/ModelBillingTokenPrices.java	Adds public RPC type for token-level pricing, including long-context tier.
java/src/main/java/com/github/copilot/rpc/ModelBilling.java	Adds tokenPrices field to ModelBilling.
go/types.go	Adds TokenPrices pointer field to ModelBilling and new pricing structs.
go/client_test.go	Adds JSON (un)marshal + round-trip test for ModelBilling.tokenPrices.
dotnet/test/Unit/SerializationTests.cs	Adds serializer round-trip test for ModelBilling.TokenPrices using SDK options.
dotnet/src/Types.cs	Adds new .NET types for token prices + source-gen registrations and adds TokenPrices to ModelBilling.

Copilot's findings

• Files reviewed: 16/16 changed files
• Comments generated: 3

[Copilot]

Copilot's findings

• Files reviewed: 16/16 changed files
• Comments generated: 0 new

[github-actions]

Cross-SDK Consistency Review ✅

This PR adds ModelBillingTokenPrices and ModelBillingTokenPricesLongContext to the public ModelBilling type and demonstrates excellent cross-SDK consistency. All six SDKs are updated in lock step.

Coverage

SDK	New Types	Exported	Tests
Node.js	ModelBillingTokenPrices, ModelBillingTokenPricesLongContext interfaces	✅ index.ts	✅
Python	ModelBillingTokenPrices, ModelBillingTokenPricesLongContext dataclasses	✅ __init__.py	✅
Go	ModelBillingTokenPrices, ModelBillingTokenPricesLongContext structs	✅ public package	✅
.NET	ModelBillingTokenPrices, ModelBillingTokenPricesLongContext sealed classes + [JsonSerializable]	✅	✅
Java	ModelBillingTokenPrices.java, ModelBillingTokenPricesLongContext.java	✅ public package	✅
Rust	Re-exported generated ModelBillingTokenPrices, ModelBillingTokenPricesLongContext	✅ types.rs	✅

API Shape Consistency

All fields are correctly mapped to language-idiomatic types and names:

Wire field	Node.js	Python	Go	.NET	Java	Rust
inputPrice	number?	float|None	*float64	double?	Double	Option<f64>
outputPrice	number?	float|None	*float64	double?	Double	Option<f64>
cachePrice	number?	float|None	*float64	double?	Double	Option<f64>
batchSize	number?	int|None	*int	int?	Integer	Option<i64>
contextMax	number?	int|None	*int	int?	Integer	Option<i64>
longContext	...|undefined	...|None	*ModelBilling...	...?	ModelBilling...	Option<...>

Noteworthy: Java multiplier type change

The PR changes Java ModelBilling.multiplier from double (primitive, non-nullable) to Double (boxed, nullable), aligning it with all other SDKs where multiplier is optional. This is a potentially breaking API change for Java consumers who stored the return value as a primitive double without null checks (auto-unboxing a null Double throws NullPointerException).

The change is correct and improves consistency — multiplier was the only SDK where this field was non-nullable — and the PR adds a specific test (testModelBillingSerializationOmitsNullMultiplier) verifying the new behavior. This is worth calling out in release notes.

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Overall, this is a thorough, well-structured update. No cross-SDK gaps found.

Generated by SDK Consistency Review Agent for issue #1633 · sonnet46 1.1M · ◷

[Copilot]

Copilot's findings

• Files reviewed: 16/16 changed files
• Comments generated: 0 new

[SteveSandersonMS]

Looks great.

@edburns Can you give an opinion on the Java breaking change (double -> Double) here? Will this be acceptable in a patch release or do we need to find an alternative?