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Model catalog boundary

Model limits, modalities, and capabilities now belong to the exact-offering catalog, keyed by (driver, wire model). Connection presets and LLMConfig contain only transport, selection, and request-default data.

This is a breaking removal. Delete contextLength, maxOutputLength, and pricing from LLMConfig, DSNs, framework configuration, and preset YAML. Use ModelCatalog::discover()->find($driver, $model) when model facts are needed. Unknown exact offerings return an explicit profile whose facts are unknown; Polyglot does not infer support from a provider name or model-name regex.

Catalog records do not contain pricing. Use InferencePricing or EmbeddingsPricing explicitly with their existing calculators when an application has sourced pricing data.

Individual model files

Runtime discovery no longer reads config/llm/models.json. Move each entry from its models list into config/llm/models/<encoded-driver>/<encoded-model>.yaml, wrapped in schemaVersion: 1, the original catalog version, and profile: <entry>. Encode driver/model filename components with ModelRecordDirectory::relativePath(new ModelKey($driver, $model)) so IDs containing / remain one model filename. See Model Catalog for a complete example.

Replace explicit runtime ModelCatalog::fromFile($jsonPath) calls with ModelCatalog::fromPaths($modelsDirectory). JSON bulk loading remains available for explicit offline maintenance; it is not a runtime fallback. Keep whole-record overrides complete enough for the facts you want to retain. Unknown keys and malformed values now fail instead of being silently discarded. Numeric limits still accept null for unknown; status fields require strings.

Ordinary inference calls do not require a catalog. A runtime constructed without models: sends requests directly through its driver and does not read model records. When an application wants local capability enforcement or model metadata, create one catalog at the composition root and reuse it across runtimes or inference objects; exact lookup then reads and caches only the selected record.

Reasoning records

Reasoning capability data now follows the same exact lookup. Replace BundledInferenceDrivers::reasoningCapabilities($driver, $model) with:

$reasoning = ModelCatalog::discover()
    ->find($driver, $model)
    ->capabilities
    ->reasoning;
// @doctest id="03e4"

Typed reasoning does not require a catalog merely to be requested. Missing or unknown facts make no local support assertion, and no model inherits facts from a provider or family pattern. A wire format that needs an exact effort mapping still requires that mapping, supplied either by an explicitly composed catalog or directly with InferenceRequest::withReasoningCapabilities(). A missing mapping is reported as missing translation data, not as proven model incompatibility.

Semantic fallback is disabled by default. Set allowLossyFallback: true on LLMConfig only when the application accepts an observable change such as JSON Schema to JSON Object or a lossy reasoning effort mapping. Laravel and Symfony connection configuration expose the same setting as llm.connections.<name>.allow_lossy_fallback. Every approved change is recorded on the effective request and emitted with InferenceRequested; provider adapters never silently degrade a request.

Failures now distinguish four cases:

• an adapter cannot encode the requested protocol operation;
• a processor needs a translation fact that was not supplied;
• an exact supplied fact explicitly marks the operation unsupported;
• a known fallback exists but the caller has not enabled lossy fallback.

Custom drivers now implement only request execution. CanDescribeCapabilities, DriverCapabilities, and SpecifiedInferenceDriver were removed. A custom spec subclass now extends BaseInferenceRequestDriver:

final class MyDriver extends BaseInferenceRequestDriver { /* override one method */ }
// @doctest id="971a"

LLMConfig::fromArray() hydrates the fields owned by LLMConfig and ignores unrelated input keys. There is no Agents-specific migration or compatibility alias.

Default registry constructors

The static BundledInferenceDrivers, BundledEmbeddingsDrivers, BundledHttpDrivers, and BundledHttpPools classes were removed. Use InferenceDriverRegistry::default(), EmbeddingsDriverRegistry::default(), HttpDriverRegistry::default(), and HttpPoolRegistry::default() respectively. Each memoized default is immutable; its with*() methods return an isolated derived registry. Use make() when an empty registry is required.

Custom Inference Drivers in v2.7

Only driver authors are affected. Preset names, Inference, PendingInference, InferenceStream, InferenceResponse, Embeddings, PendingEmbeddings, and LLMConfig are unchanged, and so is every interface under Cognesy\Polyglot\Inference\Contracts.

All 26 provider driver shells under Cognesy\Polyglot\Inference\Drivers\ were removed: A21Driver, CerebrasDriver, DeepseekDriver, FireworksDriver, GlmDriver, GroqDriver, InceptionDriver, MetaDriver, MinimaxiDriver, MistralDriver, OpenAIDriver, OpenAICompatibleDriver, OpenRouterDriver, PerplexityDriver, QwenDriver, SambaNovaDriver, XAiDriver, AnthropicDriver, AzureDriver, BedrockOpenAIDriver, CohereV2Driver, GeminiDriver, GeminiOAIDriver, HuggingFaceDriver, OpenAIResponsesDriver, and OpenResponsesDriver. Their only content was composing collaborators, so all bundled inference registrations — including native-protocol and bespoke-endpoint providers — are now InferenceDriverSpec rows in InferenceDriverRegistry, all served by one BaseInferenceRequestDriver. The embeddings driver of the same short name, Embeddings\Drivers\OpenAI\OpenAIDriver, is untouched.

Replacing a subclass of a bundled driver

Extend BaseInferenceRequestDriver and name your subclass in the spec's driverClass. It still receives the five collaborators assembled for it:

final class MyDriver extends BaseInferenceRequestDriver { /* override one method */ }

$registry = InferenceDriverRegistry::default()->withDriver(
    'my-provider',
    new InferenceDriverSpec(
        bodyFormat: MyBodyFormat::class,
        driverClass: MyDriver::class,
    ),
);
// @doctest id="743b"

If you only changed the wire format, no subclass is needed — pass your own bodyFormat, requestAdapter, responseAdapter, usageFormat, or messageFormat to the spec. Each defaults to the OpenAI implementation.

Replacing a capabilities() override

If the application needs capability inspection or local enforcement, declare the exact (driver, model) offering in a model catalog and inject that catalog into InferenceRuntime. Ordinary custom-driver execution needs no catalog. Capability inspection no longer constructs or interrogates a driver.

InferenceDriverRegistry::withDriver() still accepts a class-string or a callable, so drivers registered that way need no change.

Moved classes

Cognesy\Polyglot\Inference\Contracts\MessageMapper is now Cognesy\Polyglot\Inference\Drivers\MessageMapper — it is a driver helper, not a contract. Update the import; the class is otherwise unchanged. This one has no alias.

Five classes that neither subsystem owns moved under Cognesy\Polyglot\Support\:

Old FQCN	New FQCN
Inference\Core\SensitiveDataRedactor	Support\Redaction\SensitiveDataRedactor
Inference\Config\RetryBackoff	Support\Retry\RetryBackoff
Inference\Config\RetryJitter	Support\Retry\RetryJitter
Inference\Config\RetryPolicyInvariants	Support\Retry\RetryPolicyInvariants
Polyglot\Pricing\Cost	Support\Pricing\Cost

Polyglot 2.7 temporarily aliased the five old names. Polyglot 2.10 removes that autoloading layer completely: update every import to the new FQCN in the table. The old names no longer resolve.

Removed dead classes

Inference\Enums\InferenceContentType, Inference\Collections\InferenceResponseList, and Embeddings\Traits\HasFinders were deleted. None had a usage anywhere in the repository.

Custom Embeddings Drivers in v2.7

CanHandleVectorization now returns the domain response directly. PHP cannot provide a compatibility shim for this interface return-type change, so custom implementations must be updated together with the v2.7 package upgrade.

- public function handle(EmbeddingsRequest $request): HttpResponse;
- public function fromData(array $data): ?EmbeddingsResponse;
+ public function handle(EmbeddingsRequest $request): EmbeddingsResponse;
// @doctest id="f548"

Move HTTP response decoding and adaptation into handle(). The separate fromData() method is no longer part of the driver contract. Drivers that extend BaseEmbedDriver inherit the new behavior unless they override handle().

Migrating from v1 to v2

Polyglot 2.0 is centered around explicit request fields.

The main migration points are:

• remove old output mode usage
• set responseFormat for native JSON or JSON schema
• set tools and toolChoice for tool calling
• use stream()->deltas() for streaming

Response Model

Polyglot is now explicitly the raw inference layer.

• InferenceResponse is the final raw provider response
• streaming yields PartialInferenceDelta
• structured value ownership belongs to higher-level packages such as Instructor

If older code assumed that Polyglot streaming yielded accumulated partial response snapshots, update that code to work from deltas instead.

Before

<?php

$data = $inference
    ->with(
        messages: 'Return JSON.',
        mode: $oldMode,
    )
    ->asJsonData();
// @doctest id="e710"

After

<?php

use Cognesy\Messages\Messages;
use Cognesy\Polyglot\Inference\Data\ResponseFormat;
use Cognesy\Polyglot\Inference\Inference;

$data = Inference::using('openai')
    ->withMessages(Messages::fromString('Return JSON.'))
    ->withResponseFormat(new ResponseFormat(type: 'json_object'))
    ->asJsonData();
// @doctest id="5d5e"

Markdown-JSON fallback is no longer a Polyglot concern. Use Instructor when you need higher-level structured output strategies.

Streaming Migration

Update old streaming code like this:

• replace partial-response iteration with stream()->deltas()
• assemble final raw output with final()
• move partial structured parsing to Instructor or your own delta accumulator