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PHP API Reference

Create a new LLM client with simple scalar configuration.

This is the primary binding entry-point. All parameters except api_key are optional — omitting them uses the same defaults as ClientConfigBuilder.

Errors:

Returns LiterLlmError if the underlying HTTP client cannot be constructed, or if the resolved provider configuration is invalid.

Signature:

public static function createClient(string $apiKey, ?string $baseUrl = null, ?int $timeoutSecs = null, ?int $maxRetries = null, ?string $modelHint = null): DefaultClient

Example:

$result = createClient("value", "value", 42, 42, "value");

Parameters:

Name Type Required Description
apiKey string Yes The api key
baseUrl ?string No The base url
timeoutSecs ?int No The timeout secs
maxRetries ?int No The max retries
modelHint ?string No The model hint

Returns: DefaultClient

Errors: Throws LiterLlmError.


Create a new LLM client from a JSON string.

The JSON object accepts the same fields as liter-llm.toml (snake_case).

Errors:

Returns LiterLlmError::BadRequest if json is not valid JSON or contains unknown fields.

Signature:

public static function createClientFromJson(string $json): DefaultClient

Example:

$result = createClientFromJson("value");

Parameters:

Name Type Required Description
json string Yes The json

Returns: DefaultClient

Errors: Throws LiterLlmError.


Encode bytes as a base64 data URL: data:<mime>;base64,<b64>.

mime defaults to IMAGE_PNG when null.

Signature:

public static function encodeDataUrl(string $bytes, ?string $mime = null): string

Example:

$result = encodeDataUrl("data", "value");

Parameters:

Name Type Required Description
bytes string Yes The bytes
mime ?string No The mime

Returns: string


Decode a base64 data URL into DecodedDataUrl.

Returns null for:

  • Non-data URLs (strings that do not start with "data:").
  • Malformed prefixes (missing ";base64," marker).
  • Invalid base64 payloads.

The returned MIME string is extracted verbatim from the URL prefix — it is not validated or normalised.

Signature:

public static function decodeDataUrl(string $url): ?DecodedDataUrl

Example:

$result = decodeDataUrl("value");

Parameters:

Name Type Required Description
url string Yes The URL to fetch

Returns: ?DecodedDataUrl


Register a custom provider in the global runtime registry.

The provider will be checked before all built-in providers during model detection. If a provider with the same name already exists it is replaced.

Errors:

Returns an error if the config is invalid (empty name, empty base_url, or no model prefixes).

Signature:

public static function registerCustomProvider(CustomProviderConfig $config): void

Example:

registerCustomProvider(new CustomProviderConfig());

Parameters:

Name Type Required Description
config CustomProviderConfig Yes The configuration options

Returns: No return value.

Errors: Throws LiterLlmError.


Remove a previously registered custom provider by name.

Returns true if a provider with the given name was found and removed, false if no such provider existed.

Errors:

Returns an error if the custom-provider registry cannot be updated.

Signature:

public static function unregisterCustomProvider(string $name): bool

Example:

$result = unregisterCustomProvider("value");

Parameters:

Name Type Required Description
name string Yes The name

Returns: bool

Errors: Throws LiterLlmError.


Return the capability flags for a named provider.

Performs an O(n) linear scan over the embedded registry (165 entries). Returns an owned value so bindings can pass capability data without borrowing registry internals.

For unknown provider_name values the function returns an all-false sentinel so callers never need to handle Option.

Signature:

public static function capabilities(string $providerName): ProviderCapabilities

Example:

$result = capabilities("value");

Parameters:

Name Type Required Description
providerName string Yes The provider name

Returns: ProviderCapabilities


Return all provider configs from the registry.

Useful for tooling, documentation generation, or runtime enumeration. Returns the public ProviderConfig slice (without capability flags). To query capability flags for a specific provider use capabilities.

Signature:

public static function allProviders(): array<ProviderConfig>

Example:

$result = allProviders();

Returns: array<ProviderConfig>

Errors: Throws LiterLlmError.


Return the set of complex provider names.

Complex providers require custom auth/routing logic beyond simple bearer tokens (e.g. AWS Bedrock SigV4, Vertex AI OAuth2).

The returned reference points into the static registry — no allocation.

Signature:

public static function complexProviderNames(): array<string>

Example:

$result = complexProviderNames();

Returns: array<string>

Errors: Throws LiterLlmError.


Calculate the estimated cost of a completion given a model name and token counts.

Returns null if the model is not present in the embedded pricing registry. Returns Some(cost_usd) otherwise, where the value is in US dollars.

When an exact model name match is not found, progressively shorter prefixes are tried by stripping from the last - or . separator. For example, gpt-4-0613 will match gpt-4 if no gpt-4-0613 entry exists.

Signature:

public static function completionCost(string $model, int $promptTokens, int $completionTokens): ?float

Example:

$result = completionCost("value", 42, 42);

Parameters:

Name Type Required Description
model string Yes The model
promptTokens int Yes The prompt tokens
completionTokens int Yes The completion tokens

Returns: ?float


Calculate the estimated cost of a completion, accounting for cached (cache-hit) prompt tokens billed at the provider’s discounted rate.

cached_tokens is the count of prompt tokens served from the provider’s prompt cache. It must be <= prompt_tokens (cached tokens are a subset of the prompt). The non-cached portion is billed at input_cost_per_token and the cached portion at cache_read_input_token_cost when the model has cache pricing; otherwise the entire prompt is billed at the regular input rate.

Returns null if the model is not present in the embedded pricing registry, mirroring completion_cost.

When the model has ModelPricing::tiers, the tier whose min_context_tokens is the highest value <= prompt_tokens supplies the input/output/cache rates for the whole call; models without tiers (or when prompt_tokens is below every tier threshold) use the base rates unchanged, matching the original flat-rate behaviour.

Signature:

public static function completionCostWithCache(string $model, int $promptTokens, int $cachedTokens, int $completionTokens): ?float

Example:

$result = completionCostWithCache("value", 42, 42, 42);

Parameters:

Name Type Required Description
model string Yes The model
promptTokens int Yes The prompt tokens
cachedTokens int Yes The cached tokens
completionTokens int Yes The completion tokens

Returns: ?float


Look up FFI-friendly pricing and capability metadata for a model.

Returns null if the model is not present in the active pricing registry. Uses the same exact-match-then-prefix-fallback resolution as model_pricing; unlike model_pricing, the result is an owned ModelInfo value safe to hand across the FFI boundary.

When a runtime catalog refresh has succeeded, this reflects the refreshed (overlay) catalog; otherwise it reflects the embedded catalog. See model_pricing for the embedded-only alternative.

Signature:

public static function modelInfo(string $model): ?ModelInfo

Example:

$result = modelInfo("value");

Parameters:

Name Type Required Description
model string Yes The model

Returns: ?ModelInfo


Remove all guardrails from the global registry.

Primarily useful in tests to reset state between test cases.

Panics:

Panics if the global registry lock is poisoned.

Signature:

public static function clear(): void

Example:

clear();

Returns: No return value.


Count tokens in a text string using the tokenizer for the given model.

The tokenizer is resolved from the model name prefix (e.g. "gpt-4o" maps to the Xenova/gpt-4o HuggingFace tokenizer). Tokenizers are cached after first load.

Errors:

Returns LiterLlmError::BadRequest if the tokenizer cannot be loaded (e.g. network failure on first use) or if tokenization itself fails.

Signature:

public static function countTokens(string $model, string $text): int

Example:

$result = countTokens("value", "value");

Parameters:

Name Type Required Description
model string Yes The model
text string Yes The text

Returns: int

Errors: Throws LiterLlmError.


Count tokens for a full ChatCompletionRequest.

Sums tokens across all message text contents plus a per-message overhead of ~4 tokens (for role, separators, and formatting metadata). Tool definitions and multimodal content parts (images, audio, documents) are not counted — only textual content contributes to the token total.

Errors:

Returns LiterLlmError::BadRequest if the tokenizer cannot be loaded or if tokenization fails for any message.

Signature:

public static function countRequestTokens(string $model, ChatCompletionRequest $req): int

Example:

$result = countRequestTokens("value", new ChatCompletionRequest());

Parameters:

Name Type Required Description
model string Yes The model
req ChatCompletionRequest Yes The chat completion request

Returns: int

Errors: Throws LiterLlmError.


Assert that current_len + incoming does not exceed limit.

Call this before appending incoming bytes to any buffer that must stay below limit. Returns Err(LiterLlmError::Streaming) on overflow and emits a tracing::warn! with context.

Signature:

public static function checkBound(string $context, int $currentLen, int $incoming, int $limit): void

Example:

checkBound("value", 42, 42, 42);

Parameters:

Name Type Required Description
context string Yes The context
currentLen int Yes The current len
incoming int Yes The incoming
limit int Yes The limit

Returns: No return value.

Errors: Throws LiterLlmError.


Install the overlay registry from a raw catalog JSON string, bypassing the network and disk cache entirely.

Parses and flattens catalog_json with the same registry_from_catalog_str logic used for the embedded catalog and the network refresh path, then atomically swaps it in as the active overlay. A parse failure returns CatalogRefreshError::Parse and leaves any existing overlay untouched.

This is primarily a testable seam: it lets tests exercise overlay installation and the embedded/overlay fallback behavior in completion_cost / model_info without a real network call.

Signature:

public static function installCatalogOverlayFromStr(string $catalogJson): void

Example:

installCatalogOverlayFromStr("value");

Parameters:

Name Type Required Description
catalogJson string Yes The catalog json

Returns: No return value.

Errors: Throws CatalogRefreshError.


Clear the overlay registry, reverting completion_cost, completion_cost_with_cache, and model_info to the embedded catalog.

Primarily a test seam (see install_catalog_overlay_from_str); also usable by long-running processes that want to abandon a runtime refresh.

Signature:

public static function clearCatalogOverlay(): void

Example:

clearCatalogOverlay();

Returns: No return value.


Refresh the runtime catalog overlay per config.

  • config.enabled == false: returns Ok(RefreshOutcome::Disabled) immediately. No network, filesystem, or overlay activity.

  • A fresh on-disk cache (age < config.ttl_seconds) exists at the resolved cache path (config.cache_path, or a default under std::env::temp_dir()): read + flatten it and install the overlay, returning Ok(RefreshOutcome::FromCache). No network request is made.

  • Otherwise: validate config.source_url uses https (CatalogRefreshError::InsecureUrl otherwise), fetch it, flatten it, install the overlay, best-effort write the raw JSON to the cache path (a cache write failure does not fail the refresh), and return Ok(RefreshOutcome::Fetched).

On any error return, the overlay is left untouched: the previously active registry (a prior successful overlay, or the embedded catalog if none was ever installed) remains in effect. This is what makes the feature air-gap-safe — an unreachable or invalid source_url never degrades completion_cost / model_info below embedded-catalog availability.

Signature:

public static function refreshCatalog(CatalogRefreshConfig $config): RefreshOutcome

Example:

$result = refreshCatalog(new CatalogRefreshConfig());

Parameters:

Name Type Required Description
config CatalogRefreshConfig Yes The configuration options

Returns: RefreshOutcome

Errors: Throws CatalogRefreshError.


Assistant’s response to a user message.

Field Type Default Description
content ?AssistantContent null The assistant’s response: plain text, structured parts, or absent. null is valid when the model replies with tool calls only.
name ?string null Optional name for the assistant.
toolCalls ?array<ToolCall> \[\] Tool calls the model wants to execute, if any.
refusal ?string null Refusal reason, if the model declined to respond per safety policies.
functionCall ?FunctionCall null Deprecated legacy function_call field; retained for API compatibility.
reasoningContent ?string null Reasoning/thinking tokens returned by the provider, if any (e.g. DeepSeek R1, Qwen reasoning_content, or Anthropic extended thinking).

Return the assistant’s textual response, concatenating all Text parts if the content is structured.

Returns null for Refusal-only or OutputImage-only responses.

Signature:

public function text(): ?string

Example:

$result = $instance->text();

Returns: ?string

Return the refusal message, if the model declined to respond.

Checks both the top-level refusal field and any Refusal parts inside a structured content.

Signature:

public function refusalText(): ?string

Example:

$result = $instance->refusalText();

Returns: ?string

Return the model’s reasoning/thinking tokens, if the provider returned any.

Signature:

public function reasoningText(): ?string

Example:

$result = $instance->reasoningText();

Returns: ?string

Return all AssistantPart::OutputImage parts in the response.

Signature:

public function outputImages(): array<ImageUrl>

Example:

$result = $instance->outputImages();

Returns: array<ImageUrl>

Return all AssistantPart::OutputAudio parts in the response.

Signature:

public function outputAudio(): array<AudioContent>

Example:

$result = $instance->outputAudio();

Returns: array<AudioContent>


Audio content part for speech-capable models.

Field Type Default Description
data string Base64-encoded audio data.
format string Audio format (e.g., “wav”, “mp3”, “ogg”).

Auth configuration block.

Field Type Default Description
authType AuthType Auth scheme classification.
envVar ?string null Name of the environment variable that holds the API key (e.g. "OPENAI_API_KEY"). Holds the variable name, never the secret value.

Query parameters for listing batches.

Field Type Default Description
limit ?int null Maximum number of results to return. Defaults to 20.
after ?string null Pagination cursor: return results after this batch ID.

Response from listing batches.

Field Type Default Description
object string Object type (always "list").
data array<BatchObject> \[\] List of batch objects.
hasMore ?bool null Whether more results are available.
firstId ?string null First batch ID in the result set (for pagination).
lastId ?string null Last batch ID in the result set (for pagination).

A batch job object.

Field Type Default Description
id string Unique batch ID.
object string Object type (always "batch").
endpoint string API endpoint (e.g., "/v1/chat/completions").
inputFileId string ID of the input file.
completionWindow string Completion window (e.g., "24h").
status BatchStatus BatchStatus::Validating Current job status.
outputFileId ?string null ID of the output file (present when completed).
errorFileId ?string null ID of the error file (present if some requests failed).
createdAt int Unix timestamp of batch creation.
completedAt ?int null Unix timestamp of completion (if completed).
failedAt ?int null Unix timestamp of failure (if failed).
expiredAt ?int null Unix timestamp of expiration (if expired).
requestCounts ?BatchRequestCounts null Request processing counts.
metadata ?mixed null Metadata attached to the batch.

Request processing counts for a batch.

Field Type Default Description
total int Total requests in the batch.
completed int Completed requests.
failed int Failed requests.

AWS Bedrock configuration.

All fields are optional; anything left unset falls back to the standard AWS environment variables (AWS_DEFAULT_REGION / AWS_REGION, AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY, AWS_SESSION_TOKEN, BEDROCK_CROSS_REGION).

Field Type Default Description
region ?string null AWS region (e.g. "us-east-1").
crossRegionPrefix ?string null Cross-region inference profile prefix (e.g. "us").
accessKeyId ?string null Explicit AWS access key ID.
secretAccessKey ?string null Explicit AWS secret access key.
sessionToken ?string null Explicit AWS session token (temporary credentials).

Configuration for budget enforcement.

Field Type Default Description
globalLimit ?float null Maximum total spend across all models, in USD. null means unlimited.
modelLimits array<string, float> {} Per-model spending limits in USD. Models not listed here are only constrained by global_limit.
enforcement Enforcement Enforcement::Hard Whether to reject requests or merely warn when a limit is exceeded.

Signature:

public static function default(): BudgetConfig

Example:

$result = BudgetConfig::default();

Returns: BudgetConfig


Configuration for the response cache.

Field Type Default Description
maxEntries int 256 Maximum number of cached entries.
ttl float 300000ms Time-to-live for each cached entry.
backend CacheBackend CacheBackend::Memory Storage backend to use.

Signature:

public static function default(): CacheConfig

Example:

$result = CacheConfig::default();

Returns: CacheConfig


Plain-data configuration for refresh_catalog.

Deliberately FFI/binding-friendly: no Duration or PathBuf, just primitives that translate directly across language boundaries.

Field Type Default Description
enabled bool false Runtime catalog refresh is entirely opt-in: when false, refresh_catalog is a no-op that returns Ok(RefreshOutcome::Disabled) without touching the network, the filesystem, or the overlay registry.
sourceUrl string Source URL to fetch catalog.json from. Must be https. Defaults to DEFAULT_CATALOG_URL; configurable so self-hosted mirrors work.
ttlSeconds int 86400 How long a cached catalog.json remains valid before a network refetch is attempted, in seconds.
cachePath ?string null Filesystem path for the on-disk cache. null uses a default path under std::env::temp_dir().

Signature:

public static function default(): CatalogRefreshConfig

Example:

$result = CatalogRefreshConfig::default();

Returns: CatalogRefreshConfig


A streamed chunk of a chat completion response.

Field Type Default Description
id string Unique identifier for this stream.
object string Always "chat.completion.chunk" from OpenAI-compatible APIs. Stored as a plain String so non-standard provider values do not fail parsing.
created int Unix timestamp of chunk creation.
model string Model used to generate the chunk.
choices array<StreamChoice> \[\] Streaming choices (delta updates).
usage ?Usage null Token usage (typically only in the final chunk).
systemFingerprint ?string null Fingerprint of the system configuration (OpenAI-specific).
serviceTier ?string null Service tier used (OpenAI-specific).

Chat completion request (compatible with OpenAI and similar APIs).

Field Type Default Description
model string Model ID (e.g., "gpt-4o-mini", "claude-3-5-sonnet").
messages array<Message> \[\] Conversation history from oldest to newest.
temperature ?float null Sampling temperature in \[0.0, 2.0\]. Higher increases randomness. Defaults to 1.0.
topP ?float null Nucleus sampling parameter in \[0.0, 1.0\]. Lower is more focused.
n ?int null Number of chat completions to generate. Defaults to 1.
stream ?bool null Whether to stream the response. Managed by the client layer — do not set directly.
stop ?StopSequence null Stop sequence(s) that halt token generation.
maxTokens ?int null Max output tokens. Different from max_completion_tokens in some providers.
presencePenalty ?float null Presence penalty in \[-2.0, 2.0\]. Positive discourages repeated topics.
frequencyPenalty ?float null Frequency penalty in \[-2.0, 2.0\]. Positive discourages repeated tokens.
logitBias ?array<string, float> {} Token bias map. Uses BTreeMap (sorted keys) for deterministic serialization order — important when hashing or signing requests.
user ?string null User identifier for request tracking and abuse detection.
tools ?array<ChatCompletionTool> \[\] Tools the model can invoke.
toolChoice ?ToolChoice null Tool usage mode (auto, required, none, or specific tool).
parallelToolCalls ?bool null Whether the model can call multiple tools in parallel. Defaults to true.
responseFormat ?ResponseFormat null Output format constraint (text, JSON, JSON schema).
streamOptions ?StreamOptions null Streaming options (e.g., include_usage).
seed ?int null Random seed for reproducible outputs. Provider support varies.
reasoningEffort ?ReasoningEffort null Reasoning effort level (minimal, low, medium, high, max) for extended-thinking models.
modalities ?array<Modality> \[\] Output modalities to request from the model. For OpenAI audio models, pass \["text", "audio"\]. Vertex AI / Gemini translates these to generationConfig.responseModalities (uppercase).
extraBody ?mixed null Provider-specific extra parameters merged into the request body. Use for guardrails, safety settings, grounding config, etc.

Chat completion response from the API.

Field Type Default Description
id string Unique identifier for this response.
object string Always "chat.completion" from OpenAI-compatible APIs. Stored as a plain String so non-standard provider values do not break deserialization.
created int Unix timestamp of response creation.
model string Model used to generate the response.
choices array<Choice> \[\] List of completion choices.
usage ?Usage null Token usage statistics.
systemFingerprint ?string null Fingerprint of the system configuration (OpenAI-specific).
serviceTier ?string null Service tier used (OpenAI-specific).

A tool the model can invoke (currently, all tools are functions).

Field Type Default Description
toolType ToolType Tool type (always “function” in OpenAI spec).
function FunctionDefinition Function definition with name, description, and JSON schema parameters.

A single completion choice.

Field Type Default Description
index int Index of this choice in the choices array.
message AssistantMessage The assistant’s message response.
finishReason ?FinishReason null Why the model stopped generating (stop, length, tool_calls, content_filter, etc.).

A per-chunk transformation in the StreamPipeline.

Each middleware receives a typed chunk and returns Ok(Some(chunk)) to pass it through (optionally modified), Ok(None) to drop the chunk, or Err(e) to propagate a stream error.

The trait is object-safe so multiple middleware implementations can be chained inside StreamPipeline.

Process a single chunk.

  • Ok(Some(chunk)) — emit (possibly transformed) chunk.
  • Ok(None) — drop this chunk silently.
  • Err(e) — propagate as a stream error.

Signature:

public function process(ChatCompletionChunk $chunk): ?ChatCompletionChunk

Example:

$result = $instance->process(new ChatCompletionChunk());

Parameters:

Name Type Required Description
chunk ChatCompletionChunk Yes The chat completion chunk

Returns: ?ChatCompletionChunk

Errors: Throws LiterLlmError.


Request to create a batch job.

Field Type Default Description
inputFileId string ID of the uploaded input file (JSONL format).
endpoint string API endpoint (e.g., "/v1/chat/completions").
completionWindow string Completion window (e.g., "24h").
metadata ?mixed null Optional metadata to attach to the batch.

Request to upload a file.

Field Type Default Description
file string Base64-encoded file data.
purpose FilePurpose FilePurpose::Assistants Purpose for the file.
filename ?string null Optional filename to associate with the upload.

Request to create images from a text prompt.

Field Type Default Description
prompt string Text description of the image to generate.
model ?string null Model ID (e.g., "dall-e-3"). Optional; API may use default if unset.
n ?int null Number of images to generate. Defaults to 1.
size ?string null Image size (e.g., "1024x1024", "1792x1024").
quality ?string null Image quality: "standard" or "hd".
style ?string null Style: "natural" or "vivid" (DALL-E 3 only).
responseFormat ?string null Response format: "url" or "b64_json".
user ?string null User identifier for request tracking.

Request to create a structured response.

Field Type Default Description
model string Model ID.
input mixed Input data to process (e.g., a document to extract from).
instructions ?string null Instructions for processing the input.
tools ?array<ResponseTool> \[\] Available tools the model can use.
temperature ?float null Sampling temperature in \[0.0, 2.0\]. Defaults to 1.0.
maxOutputTokens ?int null Maximum output tokens.
metadata ?mixed null Optional metadata.
stream ?bool null Whether to stream the response. Managed by the client layer — do not set directly.

Request to generate speech audio from text.

Field Type Default Description
model string Model ID (e.g., "tts-1", "tts-1-hd").
input string Text to synthesize into speech.
voice string Voice name (e.g., "alloy", "echo", "fable", "onyx", "nova", "shimmer").
responseFormat ?string null Audio format (e.g., "mp3", "opus", "aac", "flac", "wav", "pcm").
speed ?float null Playback speed in \[0.25, 4.0\]. Defaults to 1.0.

Request to transcribe audio into text.

Field Type Default Description
model string Model ID (e.g., "whisper-1").
file string Base64-encoded audio file data.
language ?string null Language ISO-639-1 code (e.g., "en", "fr", "de"). Optional; model auto-detects.
prompt ?string null Optional text to guide the model (improves accuracy for domain-specific terms).
responseFormat ?string null Output format (e.g., "json", "text", "vtt", "srt", "verbose_json").
temperature ?float null Sampling temperature in \[0.0, 1.0\]. Higher increases variability. Defaults to 0.

Configuration for registering a custom LLM provider at runtime.

Field Type Default Description
name string Unique name for this provider (e.g., “my-provider”).
baseUrl string Base URL for the provider’s API (e.g., <https://api.my-provider.com/v1>).
authHeader AuthHeaderFormat Authentication header format.
modelPrefixes array<string> Model name prefixes that route to this provider (e.g., \["my-"\]).

Result of decoding a data: URL — MIME type and the decoded byte payload.

Named struct (rather than a tuple) so polyglot bindings can extract decode_data_url with a typed return rather than a sanitized scalar.

Field Type Default Description
mime string MIME type extracted from the URL prefix (verbatim, not normalised).
data string Decoded base64 payload.

Default client implementation backed by reqwest.

Sends requests to 165 LLM providers with automatic provider detection and per-request routing. The provider is resolved at construction time from model_hint (or defaults to OpenAI), but individual requests can override the provider via model name prefix (e.g. "anthropic/claude-3-5-sonnet" routes to Anthropic regardless of construction-time setting).

When the model prefix does not match any known provider, the construction-time provider is used as the fallback. This enables seamless migration between providers by changing only the model name.

The provider is stored behind an Arc so it can be shared cheaply into async closures and streaming tasks. Pre-computed auth headers and extra headers are cached at construction to avoid redundant encoding on every request.

Signature:

public function fetchBatchForPolling(string $batchId): BatchObject

Example:

$result = $instance->fetchBatchForPolling("value");

Parameters:

Name Type Required Description
batchId string Yes The batch id

Returns: BatchObject

Errors: Throws LiterLlmError.

Poll a batch until it reaches a terminal status (Completed, Failed, Expired, Cancelled).

Uses exponential backoff with configurable initial interval, maximum interval, and backoff multiplier. Optionally supports a timeout that aborts polling if exceeded.

Errors:

Returns BatchWaitError::Failed if the batch reaches a failure terminal status. Returns BatchWaitError::Timeout if the configured timeout is exceeded. Returns BatchWaitError::Client for underlying client errors.

Signature:

public function waitForBatch(string $batchId, WaitForBatchConfig $config): BatchObject

Example:

$result = $instance->waitForBatch("value", new WaitForBatchConfig());

Parameters:

Name Type Required Description
batchId string Yes The batch id
config WaitForBatchConfig Yes The configuration options

Returns: BatchObject

Errors: Throws BatchWaitError.


Response from a delete operation.

Field Type Default Description
id string ID of the deleted resource.
object string Object type.
deleted bool Confirmation that the resource was deleted.

Developer message (system-like message for Claude models).

Field Type Default Description
content string Developer-specific instructions or context.
name ?string null Optional name for the developer message source.

PDF/document content part for vision-capable models.

Field Type Default Description
data string Base64-encoded document data or URL.
mediaType string MIME type (e.g., “application/pdf”, “text/csv”).

A single embedding vector.

Field Type Default Description
object string Always "embedding" from OpenAI-compatible APIs. Stored as a plain String so non-standard provider values do not break deserialization.
embedding array<float> The embedding vector. Providers may return this as a JSON float array or, when encoding_format: "base64" was requested, as a base64 string of little-endian f32 bytes. Base64 responses are decoded on read; this field always serializes back out as a JSON float array.
index int Index in the batch (corresponds to input order).

Embedding request.

Field Type Default Description
model string Model ID (e.g., "text-embedding-3-small").
input EmbeddingInput EmbeddingInput::Single Text or texts to embed.
encodingFormat ?EmbeddingFormat null Output format: float (native) or base64.
dimensions ?int null Requested embedding dimensions (if supported by the model).
user ?string null User identifier for request tracking.

Embedding response.

Field Type Default Description
object string Always "list" from OpenAI-compatible APIs. Stored as a plain String so non-standard provider values do not break deserialization.
data array<EmbeddingObject> List of embeddings.
model string Model used to generate embeddings.
usage ?Usage /* serde(default) */ Token usage (input tokens only; embeddings have zero output tokens).

Query parameters for listing files.

Field Type Default Description
purpose ?string null Filter by file purpose (e.g., "batch", "fine-tune").
limit ?int null Maximum number of results to return. Defaults to 20.
after ?string null Pagination cursor: return results after this file ID.

Response from listing files.

Field Type Default Description
object string Object type (always "list").
data array<FileObject> \[\] List of file objects.
hasMore ?bool null Whether more results are available.

An uploaded file object.

Field Type Default Description
id string Unique file ID.
object string Object type (always "file").
bytes int File size in bytes.
createdAt int Unix timestamp of file creation.
filename string Filename.
purpose string File purpose.
status ?string null Processing status (e.g., "uploaded", "processed").

Function call details.

Field Type Default Description
name string Function name.
arguments string Arguments as a JSON string (parse with serde_json::from_str).

Function definition exposed to the model.

Field Type Default Description
name string Name of the function. Required and must be alphanumeric + underscores.
description ?string /* serde(default) */ Human-readable description explaining what the function does.
parameters ?mixed /* serde(default) */ JSON Schema defining the function’s parameters.
strict ?bool /* serde(default) */ If true, enforce strict JSON schema validation for arguments.

Deprecated legacy function-role message body.

Field Type Default Description
content string The extracted text content
name string The name

Abstraction over a health probe strategy.

Implementors issue a lightweight probe against upstream (typically a provider base URL or named identifier) and report HealthStatus.

Probe upstream and return its current HealthStatus.

The parameter is taken by value (String) so that implementations can move it into the returned future without a clone, making the 'static + Send bound on the future trivially satisfiable.

Signature:

public function check(string $upstream): HealthStatus

Example:

$result = $instance->check("value");

Parameters:

Name Type Required Description
upstream string Yes The upstream

Returns: HealthStatus


A single generated image, returned as either a URL or base64 data.

Field Type Default Description
url ?string null Image URL (if response_format was “url”).
b64Json ?string null Base64-encoded image data (if response_format was “b64_json”).
revisedPrompt ?string null The final prompt used to generate the image (DALL-E 3).

An image URL reference with optional detail level for processing.

Field Type Default Description
url string URL of the image (data URI or HTTP/HTTPS URL).
detail ?ImageDetail null Detail level: low (512x512), high (2x2 tiles), or auto (model-selected).

Response containing generated images.

Field Type Default Description
created int Unix timestamp of image creation.
data array<Image> \[\] List of generated images.

An intent prototype: (intent_name, prototype_embedding, target_model_id).

Field Type Default Description
name string Human-readable name for the intent (used in logs/metrics).
embedding array<float> Pre-computed embedding vector for this intent.
model string Model to route to when this intent is detected.

JSON Schema specification for constrained output.

Field Type Default Description
name string Name of the schema (must be unique in the request).
description ?string null Description of what the schema represents.
schema mixed JSON Schema object defining the output structure.
strict ?bool null If true, enforce strict schema validation.

Budget enforcement configuration.

Field Type Default Description
globalLimit ?float null Global spend limit in USD.
modelLimits ?array<string, float> {} Per-model spend limits in USD, keyed by model name.
enforcement ?string null Enforcement mode: "hard" (reject over-budget requests) or "soft" (log only).

Response cache configuration.

Field Type Default Description
maxEntries ?int null Maximum number of cached entries.
ttlSeconds ?int null Cache entry time-to-live, in seconds.
backend ?string null Cache backend name (e.g. "memory", or an opendal scheme).
backendConfig ?array<string, string> {} Backend-specific configuration key/value pairs.

Canonical configuration for an LLM client.

All fields except model are optional so that partially-specified configs (e.g. from environment-driven defaults) round-trip cleanly. Convert to a runtime client configuration via LlmConfig::into_client_builder.

temperature and max_tokens are request-time parameters rather than client-level settings; they are carried on this struct for callers to read when building individual requests, and are intentionally not mapped by LlmConfig::into_client_builder.

Field Type Default Description
model string Model identifier (e.g. "gpt-4o", "bedrock/anthropic.claude-3-sonnet-20240229-v1:0").
apiKey ?string null API key for authentication.
baseUrl ?string null Override base URL. When set, all requests go here and provider auto-detection is skipped.
timeoutSecs ?int null Request timeout, in seconds.
maxRetries ?int null Maximum number of retries on 429 / 5xx responses.
temperature ?float null Sampling temperature for requests built from this config.
maxTokens ?int null Maximum number of tokens to generate for requests built from this config.
loadEnv ?bool null Automatically load the API key from the provider’s environment variable when no explicit key is provided (default: true).
headers ?array<string, string> {} Extra headers sent on every request.
providers ?array<LlmProviderConfig> \[\] Custom provider configurations, in addition to the built-in providers.
cache ?LlmCacheConfig null Response cache configuration.
budget ?LlmBudgetConfig null Budget enforcement configuration.
rateLimit ?LlmRateLimitConfig null Per-model rate limiting configuration.
costTracking ?bool null Enable per-request cost tracking.
tracing ?bool null Enable OpenTelemetry-compatible tracing spans.
cooldownSecs ?int null Cooldown duration after transient errors, in seconds.
healthCheckSecs ?int null Background health check interval, in seconds.
bedrock ?BedrockConfig null AWS Bedrock configuration (region, credentials, cross-region routing).

Get the custom provider configurations from this config.

Signature:

public function providers(): array<LlmProviderConfig>

Example:

$result = $instance->providers();

Returns: array<LlmProviderConfig>


A custom provider configuration entry.

Field Type Default Description
name string Provider name, used to key model prefix matching.
baseUrl string Base URL for the provider’s OpenAI-compatible API.
authHeader ?string null Header name used to carry the API key (defaults to Authorization when unset).
modelPrefixes array<string> \[\] Model name prefixes routed to this provider (e.g. \["my-provider/"\]).

Per-model rate limiting configuration.

Field Type Default Description
rpm ?int null Requests per minute limit.
tpm ?int null Tokens per minute limit.
windowSeconds ?int null Rate limit window, in seconds.

Public, FFI-friendly snapshot of a model’s pricing and capability metadata, projected from ModelPricing.

Unlike ModelPricing (which is excluded from binding generation), ModelInfo is an owned plain-data DTO safe to hand across the FFI boundary — see model_info.

Field Type Default Description
inputCostPerToken float Cost in USD per input (prompt) token.
outputCostPerToken float Cost in USD per output (completion) token.
cacheReadInputTokenCost ?float null Cost in USD per cached input token (cache hit / read).
cacheCreationInputTokenCost ?float null Cost in USD per token written to the prompt cache.
inputCostPerAudioToken ?float null Cost in USD per input audio token.
outputCostPerAudioToken ?float null Cost in USD per output audio token.
outputCostPerReasoningToken ?float null Cost in USD per reasoning (extended-thinking) output token.
maxTokens ?int null Total context window size in tokens (input + output).
maxInputTokens ?int null Maximum input (prompt) tokens accepted.
maxOutputTokens ?int null Maximum output (completion) tokens the model can generate.
mode ?string null Best-effort operating mode, e.g. "chat", "embedding".
supportsVision ?bool null The model accepts image input.
supportsFunctionCalling ?bool null The model supports tool / function calling.
supportsReasoning ?bool null The model supports extended-thinking / reasoning tokens.
supportsStructuredOutput ?bool null The model supports JSON-mode or response_format structured output.
supportsAudioInput ?bool null The model accepts audio input.
supportsAudioOutput ?bool null The model can generate audio output.
supportsPromptCaching ?bool null The model supports prompt caching.
tiers array<ModelTier> \[\] Context-tiered pricing overrides, sorted by ascending min_context_tokens. Empty when the model has flat pricing.

A model available from the API.

Field Type Default Description
id string Model ID (e.g., "gpt-4o", "claude-3-5-sonnet").
object string Always "model" from OpenAI-compatible APIs. Stored as a plain String so non-standard provider values do not break deserialization. Defaults to empty when a provider omits the field.
created int Unix timestamp of model creation (or release date). Defaults to 0 when a provider omits it — DeepSeek and some other OpenAI-compatible providers do not return created from /v1/models.
ownedBy string Organization or entity that owns the model. Defaults to empty when a provider omits the field.

Public, FFI-friendly snapshot of a single context-window pricing tier, projected from PricingTier.

Field Type Default Description
minContextTokens int The tier applies when the prompt/context token count is at least this value.
inputCostPerToken float Cost in USD per input (prompt) token within this tier.
outputCostPerToken float Cost in USD per output (completion) token within this tier.
cacheReadInputTokenCost ?float null Cost in USD per cached input token within this tier.
cacheCreationInputTokenCost ?float null Cost in USD per cache-write token within this tier.
inputCostPerAudioToken ?float null Cost in USD per input audio token within this tier.
outputCostPerAudioToken ?float null Cost in USD per output audio token within this tier.
outputCostPerReasoningToken ?float null Cost in USD per reasoning output token within this tier.

Response listing available models.

Field Type Default Description
object string Always "list" from OpenAI-compatible APIs. Stored as a plain String so non-standard provider values do not break deserialization. Defaults to empty when a provider omits the field.
data array<ModelObject> \[\] List of available models.

Boolean flags for each moderation category.

Field Type Default Description
sexual bool Sexual content.
hate bool Hate speech.
harassment bool Harassment.
selfHarm bool Self-harm content.
sexualMinors bool Sexual content involving minors.
hateThreatening bool Hate speech that threatens violence.
violenceGraphic bool Graphic violence.
selfHarmIntent bool Intent to self-harm.
selfHarmInstructions bool Instructions for self-harm.
harassmentThreatening bool Harassment that threatens violence.
violence bool Non-graphic violence.

Confidence scores for each moderation category.

Field Type Default Description
sexual float Sexual content score.
hate float Hate speech score.
harassment float Harassment score.
selfHarm float Self-harm content score.
sexualMinors float Sexual content involving minors score.
hateThreatening float Hate speech that threatens violence score.
violenceGraphic float Graphic violence score.
selfHarmIntent float Intent to self-harm score.
selfHarmInstructions float Instructions for self-harm score.
harassmentThreatening float Harassment that threatens violence score.
violence float Non-graphic violence score.

Request to classify content for policy violations.

Field Type Default Description
input ModerationInput ModerationInput::Single Text or texts to check.
model ?string null Model ID (e.g., "text-moderation-latest"). Optional; API uses default if unset.

Response from the moderation endpoint.

Field Type Default Description
id string Unique identifier for this moderation request.
model string Model used for classification.
results array<ModerationResult> Results for each input string.

A single moderation classification result.

Field Type Default Description
flagged bool True if any category was flagged.
categories ModerationCategories Boolean flags for each moderation category.
categoryScores ModerationCategoryScores Confidence scores for each category.

An image extracted from an OCR page.

Field Type Default Description
id string Unique image identifier within the document.
imageBase64 ?string /* serde(default) */ Base64-encoded image data (if include_image_base64 was true).

A single page of OCR output.

Field Type Default Description
index int Page index (0-based).
markdown string Extracted page content as Markdown.
images ?array<OcrImage> /* serde(default) */ Embedded images extracted from the page (if include_image_base64 was true).
dimensions ?PageDimensions /* serde(default) */ Page dimensions in pixels, if available.

An OCR request.

Field Type Default Description
model string The model/provider to use (e.g. "mistral/mistral-ocr-latest").
document OcrDocument OcrDocument::Url The document to process (URL or base64).
pages ?array<int> \[\] Specific pages to process (1-indexed). null means all pages.
includeImageBase64 ?bool null Whether to include base64-encoded images of each processed page.

An OCR response.

Field Type Default Description
pages array<OcrPage> Extracted pages in order.
model string Model/provider used for OCR.
usage ?Usage /* serde(default) */ Token usage, if reported by the provider.

Page dimensions in pixels.

Field Type Default Description
width int Width in pixels.
height int Height in pixels.

Breakdown of tokens used in the prompt portion of a request.

cached_tokens is included in Usage::prompt_tokens — it is not an additional charge on top of the prompt token count. When pricing supports a cache_read_input_token_cost, the cached portion is billed at the discounted rate and the remainder at the regular input rate.

Field Type Default Description
cachedTokens int Cached tokens present in the prompt. Defaults to 0 when absent.
audioTokens int Audio input tokens present in the prompt. Defaults to 0 when absent.

Static capability flags for a provider.

Each flag indicates whether the provider’s models generally support that feature. For providers that aggregate many underlying models (e.g. Bedrock, OpenRouter, vLLM) the flags reflect the superset of available model capabilities — a flag being true means at least one model supports the feature, not every model.

All flags default to false so that newly added providers are safe.

Access via the crate-level capabilities function:

Field Type Default Description
vision bool The provider accepts image input in chat messages.
reasoning bool The provider supports extended-thinking / reasoning tokens.
structuredOutput bool The provider supports JSON-mode or response_format structured output.
functionCalling bool The provider supports tool / function calling.
audioIn bool The provider accepts audio as input.
audioOut bool The provider can generate audio / TTS output.
videoIn bool The provider accepts video as input.

Static configuration for a single provider entry in providers.json.

This struct deliberately does not include capability flags or streaming format, which are accessed via the capabilities function.

Field Type Default Description
name string Provider identifier (matches the entry key in providers.json).
displayName ?string null Human-readable provider name shown in UIs.
baseUrl ?string null Base URL used as the default for this provider’s HTTP client.
auth ?AuthConfig null Authentication scheme metadata (auth type + env var holding the key).
endpoints ?array<string> null Supported endpoint kinds (e.g. chat, embeddings).
modelPrefixes ?array<string> null Model-name prefixes claimed by this provider (e.g. \["gpt-", "o1-"\]).
paramMappings ?array<string, string> null Parameter key renaming for this provider. Each entry maps an OpenAI-spec field name (e.g. "max_completion_tokens") to the name this provider expects (e.g. "max_tokens"). Applied automatically by ConfigDrivenProvider::transform_request.

Configuration for per-model rate limits.

Field Type Default Description
rpm ?int null Maximum requests per window. null means unlimited.
tpm ?int null Maximum tokens per window. null means unlimited.
window float 60000ms Fixed window duration (defaults to 60 s).

Signature:

public static function default(): RateLimitConfig

Example:

$result = RateLimitConfig::default();

Returns: RateLimitConfig


Request to rerank documents by relevance to a query.

Field Type Default Description
model string Model ID (e.g., "cohere/rerank-english-v3.0").
query string The search query.
documents array<RerankDocument> \[\] Documents to rerank.
topN ?int null Return only the top N results. Optional.
returnDocuments ?bool null Include the document content in results. Defaults to false.

Response from the rerank endpoint.

Field Type Default Description
id ?string null Unique identifier for this rerank request.
results array<RerankResult> Reranked documents in order of relevance.
meta ?mixed /* serde(default) */ Optional metadata about the reranking operation.

A single reranked document with its relevance score.

Field Type Default Description
index int Original document index in the input list.
relevanceScore float Relevance score in \[0, 1\]. Higher indicates more relevant.
document ?RerankResultDocument /* serde(default) */ Original document content (if return_documents was true).

The text content of a reranked document, returned when return_documents is true.

Field Type Default Description
text string Document text.

Response from a structured response request.

Field Type Default Description
id string Unique response ID.
object string Object type (e.g., "response").
createdAt int Unix timestamp of response creation.
model string Model used to generate the response.
status string Status (e.g., "succeeded", "failed").
output array<ResponseOutputItem> \[\] Output items from the response.
usage ?ResponseUsage null Token usage.
error ?mixed null Error details (if status is “failed”).

A single output item from the response.

Field Type Default Description
itemType string Output type (e.g., "text", "object", "error").
content mixed Output content (flattened into the object).

A tool available for the response request.

Field Type Default Description
toolType string Tool type (e.g., “extractor”, “search”).
config mixed Tool configuration (flattened into the object).

Token usage for a response.

Field Type Default Description
inputTokens int Input tokens used.
outputTokens int Output tokens used.
totalTokens int Total tokens used.

A search request.

Field Type Default Description
model string The model/provider to use (e.g. "brave/web-search", "tavily/search").
query string The search query string.
maxResults ?int null Maximum number of results to return.
searchDomainFilter ?array<string> \[\] Domain filter — restrict results to specific domains.
country ?string null Country code for localized results (ISO 3166-1 alpha-2, e.g., "US", "FR").

A search response.

Field Type Default Description
results array<SearchResult> List of search results.
model string Model/provider that performed the search.

An individual search result.

Field Type Default Description
title string Result title.
url string Result URL.
snippet string Text snippet or excerpt from the page.
date ?string /* serde(default) */ Publication or last-updated date, if available.

The value broadcast from a singleflight leader to all followers.

The error value is shared so every follower receives the same upstream failure without cloning the underlying error.


Name of the specific function to invoke.

Field Type Default Description
name string Function name.

Directive to call a specific tool.

Field Type Default Description
choiceType ToolType ToolType::Function Tool type (always “function”).
function SpecificFunction The specific function to invoke.

A streaming choice with incremental delta.

Field Type Default Description
index int Index of this choice in the choices array.
delta StreamDelta Incremental update to the message (content, tool calls, etc.).
finishReason ?FinishReason null Why the stream ended (present only in final chunk).

Incremental delta in a stream chunk.

Field Type Default Description
role ?string null Role (typically present only in the first chunk).
content ?string null Partial content chunk (e.g., a few words of the response).
toolCalls ?array<StreamToolCall> \[\] Partial tool calls being streamed.
functionCall ?StreamFunctionCall null Deprecated legacy function_call delta; retained for API compatibility.
refusal ?string null Partial refusal message.
reasoningContent ?string null Partial reasoning/thinking tokens (OpenAI-compatible extension used by DeepSeek R1, Qwen, etc.).

Partial function call details in a stream.

Field Type Default Description
name ?string null Function name (typically in the first chunk).
arguments ?string null Partial JSON arguments chunk.

Options for streaming responses.

Field Type Default Description
includeUsage ?bool null If true, include token usage in the final stream chunk.

A streaming tool call being built incrementally.

Field Type Default Description
index int Index of this tool call in the tool_calls array.
id ?string null Tool call ID (typically in the first chunk for this call).
callType ?ToolType null Tool type (typically “function”).
function ?StreamFunctionCall null Partial function name and arguments.

System message guiding model behavior for the entire conversation.

Field Type Default Description
content UserContent UserContent::Text Instructions or context that apply throughout the conversation. Accepts either a plain text string or an array of content parts, mirroring UserContent so that Message::system_with_parts works.
name ?string null Optional name for the system message source.

A tool call the model wants to execute.

Field Type Default Description
id string Unique ID for this call, used to reference in tool result messages.
callType ToolType Tool type (always “function”).
function FunctionCall Function name and arguments.

Tool execution result returned to the model.

Field Type Default Description
content UserContent UserContent::Text Result of the tool execution as plain text or an array of content parts (text, images, documents, audio), mirroring UserMessage::content. #\[serde(untagged)\] on UserContent means a bare JSON string still deserialises into Text, so tool results persisted before this field carried structured content continue to round-trip.
toolCallId string ID of the tool call this result responds to.
name ?string null Optional tool/function name.

Response from a transcription request.

Field Type Default Description
text string The transcribed text.
language ?string null Detected language (ISO-639-1 code).
duration ?float null Total audio duration in seconds.
segments ?array<TranscriptionSegment> \[\] Detailed segment-level transcription (if response_format is “verbose_json”).

A segment of transcribed audio with timing information.

Field Type Default Description
id int Segment index (0-based).
start float Start time in seconds.
end float End time in seconds.
text string Transcribed text for this segment.

Token-usage accounting returned by the provider on each completion / embedding call.

Field Type Default Description
promptTokens int Prompt tokens used. Defaults to 0 when absent (some providers omit this).
completionTokens int Completion tokens used. Defaults to 0 when absent (e.g. embedding responses).
totalTokens int Total tokens used. Defaults to 0 when absent (some providers omit this).
promptTokensDetails ?PromptTokensDetails null Breakdown of tokens used in the prompt, including cached tokens served at the provider’s discounted cache-read rate. Absent when the provider does not return prompt-token details.

User message in the conversation.

Field Type Default Description
content UserContent UserContent::Text Message content as plain text or array of content parts (text, images, documents, audio).
name ?string null Optional name for the user.

Configuration for polling a batch until terminal status.

All time values are in seconds as f64 so the struct bridges across FFI boundaries without requiring a Duration shim.

Field Type Default Description
initialIntervalSecs float 5 Initial interval between polls, in seconds.
maxIntervalSecs float 60 Maximum interval between polls (backoff plateau), in seconds.
backoffMultiplier float 1.5 Exponential backoff multiplier (e.g., 1.5 increases delay by 50% each poll).
timeoutSecs ?float null Optional timeout in seconds — polling fails if this duration is exceeded.

Signature:

public static function default(): WaitForBatchConfig

Example:

$result = WaitForBatchConfig::default();

Returns: WaitForBatchConfig


A chat message in a conversation.

Value Description
System System — Fields: 0: SystemMessage
User User — Fields: 0: UserMessage
Assistant Assistant — Fields: 0: AssistantMessage
Tool Tool — Fields: 0: ToolMessage
Developer Developer — Fields: 0: DeveloperMessage
Function Deprecated legacy function-role message; retained for API compatibility. — Fields: 0: FunctionMessage

User message content as either plain text or a list of multimodal parts.

Value Description
Text Plain text content. — Fields: 0: string
Parts Array of content parts (text, images, documents, audio). — Fields: 0: array<ContentPart>

A single content part in a user message — text, image, document, or audio.

Value Description
Text Plain text. — Fields: text: string
ImageUrl Image identified by URL (with optional detail level). — Fields: imageUrl: ImageUrl
Document Document file (PDF, CSV, etc.) as base64 or URL. — Fields: document: DocumentContent
InputAudio Audio input as base64. — Fields: inputAudio: AudioContent

Image detail level controlling token cost and processing.

Value Description
Low Low detail: scales image to 512x512, uses fewer tokens.
High High detail: processes up to 2x2 grid of tiles, higher token cost.
Auto Auto: model chooses low or high based on image dimensions.

Content shape for assistant messages.

#[serde(untagged)] means providers returning a plain scalar string for the content field still deserialise correctly into AssistantContent::Text(_). Providers returning an array of typed parts (e.g. after an image-generation or audio-synthesis request) deserialise into AssistantContent::Parts(_).

Value Description
Text Plain text response (the common case for text-only models). — Fields: 0: string
Parts Structured parts — text, refusals, output images, output audio. — Fields: 0: array<AssistantPart>

One part of a structured assistant response.

#[serde(tag = "type", rename_all = "snake_case")] matches OpenAI’s parts-spec discriminator ("type": "text", "type": "output_image", …).

Value Description
Text A text segment of the response. — Fields: text: string
Refusal A refusal — the model declined to respond. — Fields: refusal: string
OutputImage An image produced by the model (e.g. gpt-image-1, Gemini Imagen). — Fields: imageUrl: ImageUrl
OutputAudio Audio produced by the model (e.g. gpt-4o-audio-preview). — Fields: audio: AudioContent

The type discriminator for tool/tool-call objects.

Per the OpenAI spec this is always "function". Using an enum enforces that constraint at the type level and rejects any other value on deserialization.

Value Description
Function Function

Tool usage mode or a specific tool to call.

Value Description
Mode Predefined mode: auto, required, or none. — Fields: 0: ToolChoiceMode
Specific Force a specific tool to be called. — Fields: 0: SpecificToolChoice

Tool choice mode.

Value Description
Auto Model may or may not call tools; default behavior.
Required Model must call at least one tool.
None Model must not call any tools.

Wire format for the chat completions response_format field.

  • OpenAI (and OpenAI-compatible providers): emitted verbatim as {"type": "json_schema", "json_schema": {...}} per the chat-completions spec.

  • Gemini / Vertex AI: translated to generationConfig.responseMimeType = "application/json" and generationConfig.responseSchema = <schema>. The name, description, and strict fields are dropped — Gemini’s structured-output API does not consume them.

  • Anthropic: no native JSON mode. A system instruction is prepended asking the model to respond with valid JSON. strict is advisory only; callers should still validate the returned JSON if the schema is load-bearing.

Value Description
Text Plain text output (default).
JsonObject Output must be valid JSON object (no schema validation).
JsonSchema Output must conform to the specified JSON schema. — Fields: jsonSchema: JsonSchemaFormat

Stop sequence(s) that cause the model to stop generating.

Value Description
Single Single stop sequence. — Fields: 0: string
Multiple Multiple stop sequences. — Fields: 0: array<string>

Output modality requested from the model.

Passed as modalities: ["text", "audio"] (OpenAI) or translated to generationConfig.responseModalities (Gemini / Vertex AI).

Value Description
Text Text output (the default for all providers).
Audio Audio / speech output.
Image Image output (Gemini Imagen, gpt-image-1).

Why a choice stopped generating tokens.

Value Description
Stop Stop
Length Length
ToolCalls Tool calls
ContentFilter Content filter
FunctionCall Deprecated legacy finish reason; retained for API compatibility.
Other Catch-all for unknown finish reasons returned by non-OpenAI providers. Note: this intentionally does not carry the original string (e.g. Other(String)). Using #\[serde(other)\] requires a unit variant, and switching to #\[serde(untagged)\] would change deserialization semantics for all variants. The original value can be recovered by inspecting the raw JSON if needed.

Controls how much reasoning effort the model should use.

Value Description
Low Low
Medium Medium
High High
Minimal Minimal
Max Max

The format in which the embedding vectors are returned.

Value Description
Float 32-bit floating-point numbers (default).
Base64 Base64-encoded string representation of the floats.

Text or texts to embed.

Value Description
Single Single text string. — Fields: 0: string
Multiple Multiple text strings (batch embedding). — Fields: 0: array<string>

Input to the moderation endpoint — a single string or multiple strings.

Value Description
Single Single text string. — Fields: 0: string
Multiple Multiple text strings (batch moderation). — Fields: 0: array<string>

A document to be reranked — either a plain string or an object with a text field.

Value Description
Text Plain text document content. — Fields: 0: string
Object Document with explicit text field (may include metadata). — Fields: text: string

Document input for OCR — either a URL or inline base64 data.

Value Description
Url A publicly accessible document URL. — Fields: url: string
Base64 Inline base64-encoded document data. — Fields: data: string, mediaType: string

Purpose of an uploaded file.

Value Description
Assistants File for use with Assistants API.
Batch File for batch processing.
FineTune File for fine-tuning.
Vision File for vision/image tasks.

Status of a batch job.

Value Description
Validating Validating the input file.
Failed Job failed.
InProgress Job is running.
Finalizing Finalizing results.
Completed Job completed successfully.
Expired Job expired before completion.
Cancelling Job is being cancelled.
Cancelled Job has been cancelled.

How the API key is sent in the HTTP request.

Value Description
Bearer Bearer token: Authorization: Bearer <key>
ApiKey Custom header: e.g., X-Api-Key: <key> — Fields: 0: string
None No authentication required.

The streaming wire format a provider uses for its response stream.

Most providers use standard Server-Sent Events (SSE). AWS Bedrock uses a proprietary binary EventStream framing.

Deserialized from the streaming_format JSON field via serde.

Value Description
Sse Standard Server-Sent Events (text/event-stream).
AwsEventStream AWS EventStream binary framing (application/vnd.amazon.eventstream).

Auth scheme used by a provider.

Value Description
Bearer Standard Authorization: Bearer <key> header.
ApiKey x-api-key: <key> header (also handles "header" and "x-api-key" aliases).
None No authentication header required.
Unknown Unrecognised auth scheme — falls back to bearer.

How budget limits are enforced.

Value Description
Hard Reject requests that would exceed the budget with LiterLlmError::BudgetExceeded.
Soft Allow requests through but emit a tracing::warn! when the budget is exceeded.

Storage backend for the response cache.

Value Description
Memory In-memory LRU cache (default). No external dependencies.
OpenDal OpenDAL-backed storage. Supports 40+ backends (S3, Redis, GCS, local FS, etc.). — Fields: scheme: string, config: array<string, string>

Observable state of a circuit breaker.

Value Description
Closed Requests flow through normally.
Open All requests are rejected; the circuit is waiting for the backoff to elapse.
HalfOpen One probe request is allowed through to test service health.

The result of a single health probe.

Value Description
Healthy The probe succeeded; the upstream is reachable.
Unhealthy The probe failed; the upstream may be down.

Result of a refresh_catalog call.

Value Description
Disabled config.enabled was false; no network, filesystem, or overlay activity occurred.
FromCache The on-disk cache was fresh (age < ttl_seconds); the overlay was installed from the cached file without a network request.
Fetched The catalog was fetched over the network, the cache file was (best-effort) refreshed, and the overlay was installed from the fetched catalog.

All errors that can occur when using liter-llm.

Variant Description
Authentication status preserves the exact HTTP status code received (401 or 403).
RateLimited rate limited: {message}
BadRequest status preserves the exact HTTP status code received (400, 405, 413, 422, …).
ContextWindowExceeded context window exceeded: {message}
ContentPolicy content policy violation: {message}
NotFound not found: {message}
ServerError status preserves the exact HTTP status code received (500, or other 5xx not covered by ServiceUnavailable).
ServiceUnavailable status preserves the exact HTTP status code received (502, 503, or 504).
Timeout request timeout
Streaming A catch-all for errors that occur during streaming response processing. This variant covers multiple sub-conditions including UTF-8 decoding failures, CRC/checksum mismatches (AWS EventStream), JSON parse errors in individual SSE chunks, and buffer overflow conditions. The message field contains a human-readable description of the specific failure.
EndpointNotSupported provider {provider} does not support {endpoint}
InvalidHeader invalid header {name:?}: {reason}
Serialization serialization error: {0}
BudgetExceeded budget exceeded: {message}
HookRejected hook rejected: {message}
InternalError An internal logic error (e.g. unexpected Tower response variant). This should never surface in normal operation — if it does, it indicates a bug in the library.
OutboundForbidden An outbound request was blocked by the active OutboundPolicy. Returned when register_custom_provider is called with a base_url that violates the policy (e.g. a private-range IP under DenyPrivate), or when the per-connection DNS resolver detects a forbidden address at connect time.
IdempotencyConflict A different request body was submitted for an existing Idempotency-Key. Per the OpenAI Idempotency-Key convention, once a key is used with a particular request body, subsequent requests using the same key must carry an identical body. A body mismatch is a hard error (not retryable). HTTP equivalent: 409 Conflict.
IdempotencyInFlight The same Idempotency-Key is already in-flight (another request with the same key is currently being processed). The caller should wait briefly and retry. The response is not yet available, and this request has been short-circuited to avoid running the operation twice. HTTP equivalent: 409 Conflict (retryable after a brief delay).

Errors from refresh_catalog and install_catalog_overlay_from_str.

On every variant, the overlay registry is left untouched: a previously installed overlay (or the embedded catalog, if none was ever installed) remains active. This is the air-gap-safety contract — a failed refresh never degrades pricing/model-info availability.

Variant Description
Disabled Runtime catalog refresh was not enabled. refresh_catalog itself never returns this — it returns Ok(RefreshOutcome::Disabled) instead — but the variant is part of the public error surface for callers that want to treat “disabled” as a hard error.
InsecureUrl source_url did not use the https scheme, or failed to parse as a URL at all. There is no host allowlist: the URL is user-configurable for self-hosted catalog mirrors, so only the scheme is enforced.
Fetch The network fetch failed, timed out, or returned a non-success status.
Parse The fetched or cached catalog JSON failed to parse.
Cache A cache file read failed on an otherwise-fresh cache file. Cache write failures are best-effort and never surface as this error (see refresh_catalog).