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Configuration Reference

Configuration Reference

This page documents all configuration types and their defaults across all languages.

SystemMessage

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 str \| None None Optional name for the system message source.

UserMessage

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 str \| None None Optional name for the user.

ImageUrl

An image URL reference with optional detail level for processing.

Field Type Default Description
url str URL of the image (data URI or HTTP/HTTPS URL).
detail ImageDetail \| None None Detail level: low (512x512), high (2x2 tiles), or auto (model-selected).

DocumentContent

PDF/document content part for vision-capable models.

Field Type Default Description
data str Base64-encoded document data or URL.
media_type str MIME type (e.g., "application/pdf", "text/csv").

AudioContent

Audio content part for speech-capable models.

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

AssistantMessage

Assistant's response to a user message.

Field Type Default Description
content AssistantContent \| None None The assistant's response: plain text, structured parts, or absent. None is valid when the model replies with tool calls only.
name str \| None None Optional name for the assistant.
tool_calls list\[ToolCall\] \| None \[\] Tool calls the model wants to execute, if any.
refusal str \| None None Refusal reason, if the model declined to respond per safety policies.
function_call FunctionCall \| None None Deprecated legacy function_call field; retained for API compatibility.

ToolMessage

Tool execution result returned to the model.

Field Type Default Description
content str Result of the tool execution.
tool_call_id str ID of the tool call this result responds to.
name str \| None None Optional tool/function name.

DeveloperMessage

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

Field Type Default Description
content str Developer-specific instructions or context.
name str \| None None Optional name for the developer message source.

FunctionMessage

Deprecated legacy function-role message body.

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

SpecificToolChoice

Directive to call a specific tool.

Field Type Default Description
choice_type ToolType ToolType.FUNCTION Tool type (always "function").
function SpecificFunction The specific function to invoke.

SpecificFunction

Name of the specific function to invoke.

Field Type Default Description
name str Function name.

JsonSchemaFormat

JSON Schema specification for constrained output.

Field Type Default Description
name str Name of the schema (must be unique in the request).
description str \| None None Description of what the schema represents.
schema dict\[str, Any\] JSON Schema object defining the output structure.
strict bool \| None None If true, enforce strict schema validation.

Usage

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

Field Type Default Description
prompt_tokens int Prompt tokens used. Defaults to 0 when absent (some providers omit this).
completion_tokens int Completion tokens used. Defaults to 0 when absent (e.g. embedding responses).
total_tokens int Total tokens used. Defaults to 0 when absent (some providers omit this).
prompt_tokens_details PromptTokensDetails \| None None 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.

PromptTokensDetails

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
cached_tokens int Cached tokens present in the prompt. Defaults to 0 when absent.
audio_tokens int Audio input tokens present in the prompt. Defaults to 0 when absent.

ChatCompletionRequest

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

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

StreamOptions

Options for streaming responses.

Field Type Default Description
include_usage bool \| None None If true, include token usage in the final stream chunk.

ChatCompletionResponse

Chat completion response from the API.

Field Type Default Description
id str Unique identifier for this response.
object str 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 str Model used to generate the response.
choices list\[Choice\] \[\] List of completion choices.
usage Usage \| None None Token usage statistics.
system_fingerprint str \| None None Fingerprint of the system configuration (OpenAI-specific).
service_tier str \| None None Service tier used (OpenAI-specific).

Choice

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.
finish_reason FinishReason \| None None Why the model stopped generating (stop, length, tool_calls, content_filter, etc.).

ChatCompletionChunk

A streamed chunk of a chat completion response.

Field Type Default Description
id str Unique identifier for this stream.
object str 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 str Model used to generate the chunk.
choices list\[StreamChoice\] \[\] Streaming choices (delta updates).
usage Usage \| None None Token usage (typically only in the final chunk).
system_fingerprint str \| None None Fingerprint of the system configuration (OpenAI-specific).
service_tier str \| None None Service tier used (OpenAI-specific).

StreamChoice

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.).
finish_reason FinishReason \| None None Why the stream ended (present only in final chunk).

StreamDelta

Incremental delta in a stream chunk.

Field Type Default Description
role str \| None None Role (typically present only in the first chunk).
content str \| None None Partial content chunk (e.g., a few words of the response).
tool_calls list\[StreamToolCall\] \| None \[\] Partial tool calls being streamed.
function_call StreamFunctionCall \| None None Deprecated legacy function_call delta; retained for API compatibility.
refusal str \| None None Partial refusal message.

StreamToolCall

A streaming tool call being built incrementally.

Field Type Default Description
index int Index of this tool call in the tool_calls array.
id str \| None None Tool call ID (typically in the first chunk for this call).
call_type ToolType \| None None Tool type (typically "function").
function StreamFunctionCall \| None None Partial function name and arguments.

StreamFunctionCall

Partial function call details in a stream.

Field Type Default Description
name str \| None None Function name (typically in the first chunk).
arguments str \| None None Partial JSON arguments chunk.

EmbeddingRequest

Embedding request.

Field Type Default Description
model str Model ID (e.g., "text-embedding-3-small").
input EmbeddingInput EmbeddingInput.SINGLE Text or texts to embed.
encoding_format EmbeddingFormat \| None None Output format: float (native) or base64.
dimensions int \| None None Requested embedding dimensions (if supported by the model).
user str \| None None User identifier for request tracking.

CreateImageRequest

Request to create images from a text prompt.

Field Type Default Description
prompt str Text description of the image to generate.
model str \| None None Model ID (e.g., "dall-e-3"). Optional; API may use default if unset.
n int \| None None Number of images to generate. Defaults to 1.
size str \| None None Image size (e.g., "1024x1024", "1792x1024").
quality str \| None None Image quality: "standard" or "hd".
style str \| None None Style: "natural" or "vivid" (DALL-E 3 only).
response_format str \| None None Response format: "url" or "b64_json".
user str \| None None User identifier for request tracking.

ImagesResponse

Response containing generated images.

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

Image

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

Field Type Default Description
url str \| None None Image URL (if response_format was "url").
b64_json str \| None None Base64-encoded image data (if response_format was "b64_json").
revised_prompt str \| None None The final prompt used to generate the image (DALL-E 3).

DecodedDataUrl

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 str MIME type extracted from the URL prefix (verbatim, not normalised).
data bytes Decoded base64 payload.

CreateSpeechRequest

Request to generate speech audio from text.

Field Type Default Description
model str Model ID (e.g., "tts-1", "tts-1-hd").
input str Text to synthesize into speech.
voice str Voice name (e.g., "alloy", "echo", "fable", "onyx", "nova", "shimmer").
response_format str \| None None Audio format (e.g., "mp3", "opus", "aac", "flac", "wav", "pcm").
speed float \| None None Playback speed in \[0.25, 4.0\]. Defaults to 1.0.

CreateTranscriptionRequest

Request to transcribe audio into text.

Field Type Default Description
model str Model ID (e.g., "whisper-1").
file str Base64-encoded audio file data.
language str \| None None Language ISO-639-1 code (e.g., "en", "fr", "de"). Optional; model auto-detects.
prompt str \| None None Optional text to guide the model (improves accuracy for domain-specific terms).
response_format str \| None None Output format (e.g., "json", "text", "vtt", "srt", "verbose_json").
temperature float \| None None Sampling temperature in \[0.0, 1.0\]. Higher increases variability. Defaults to 0.

TranscriptionResponse

Response from a transcription request.

Field Type Default Description
text str The transcribed text.
language str \| None None Detected language (ISO-639-1 code).
duration float \| None None Total audio duration in seconds.
segments list\[TranscriptionSegment\] \| None \[\] Detailed segment-level transcription (if response_format is "verbose_json").

TranscriptionSegment

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 str Transcribed text for this segment.

ModerationRequest

Request to classify content for policy violations.

Field Type Default Description
input ModerationInput ModerationInput.SINGLE Text or texts to check.
model str \| None None Model ID (e.g., "text-moderation-latest"). Optional; API uses default if unset.

ModerationCategories

Boolean flags for each moderation category.

Field Type Default Description
sexual bool Sexual content.
hate bool Hate speech.
harassment bool Harassment.
self_harm bool Self-harm content.
sexual_minors bool Sexual content involving minors.
hate_threatening bool Hate speech that threatens violence.
violence_graphic bool Graphic violence.
self_harm_intent bool Intent to self-harm.
self_harm_instructions bool Instructions for self-harm.
harassment_threatening bool Harassment that threatens violence.
violence bool Non-graphic violence.

ModerationCategoryScores

Confidence scores for each moderation category.

Field Type Default Description
sexual float Sexual content score.
hate float Hate speech score.
harassment float Harassment score.
self_harm float Self-harm content score.
sexual_minors float Sexual content involving minors score.
hate_threatening float Hate speech that threatens violence score.
violence_graphic float Graphic violence score.
self_harm_intent float Intent to self-harm score.
self_harm_instructions float Instructions for self-harm score.
harassment_threatening float Harassment that threatens violence score.
violence float Non-graphic violence score.

RerankRequest

Request to rerank documents by relevance to a query.

Field Type Default Description
model str Model ID (e.g., "cohere/rerank-english-v3.0").
query str The search query.
documents list\[RerankDocument\] \[\] Documents to rerank.
top_n int \| None None Return only the top N results. Optional.
return_documents bool \| None None Include the document content in results. Defaults to false.

SearchRequest

A search request.

Field Type Default Description
model str The model/provider to use (e.g. "brave/web-search", "tavily/search").
query str The search query string.
max_results int \| None None Maximum number of results to return.
search_domain_filter list\[str\] \| None \[\] Domain filter — restrict results to specific domains.
country str \| None None Country code for localized results (ISO 3166-1 alpha-2, e.g., "US", "FR").

OcrRequest

An OCR request.

Field Type Default Description
model str The model/provider to use (e.g. "mistral/mistral-ocr-latest").
document OcrDocument OcrDocument.URL The document to process (URL or base64).
pages list\[int\] \| None \[\] Specific pages to process (1-indexed). None means all pages.
include_image_base64 bool \| None None Whether to include base64-encoded images of each processed page.

ModelsListResponse

Response listing available models.

Field Type Default Description
object str Always "list" from OpenAI-compatible APIs. Stored as a plain String so non-standard provider values do not break deserialization.
data list\[ModelObject\] \[\] List of available models.

ModelObject

A model available from the API.

Field Type Default Description
id str Model ID (e.g., "gpt-4o", "claude-3-5-sonnet").
object str Always "model" from OpenAI-compatible APIs. Stored as a plain String so non-standard provider values do not break deserialization.
created int Unix timestamp of model creation (or release date).
owned_by str Organization or entity that owns the model.

CreateFileRequest

Request to upload a file.

Field Type Default Description
file str Base64-encoded file data.
purpose FilePurpose FilePurpose.ASSISTANTS Purpose for the file.
filename str \| None None Optional filename to associate with the upload.

FileObject

An uploaded file object.

Field Type Default Description
id str Unique file ID.
object str Object type (always "file").
bytes int File size in bytes.
created_at int Unix timestamp of file creation.
filename str Filename.
purpose str File purpose.
status str \| None None Processing status (e.g., "uploaded", "processed").

FileListResponse

Response from listing files.

Field Type Default Description
object str Object type (always "list").
data list\[FileObject\] \[\] List of file objects.
has_more bool \| None None Whether more results are available.

FileListQuery

Query parameters for listing files.

Field Type Default Description
purpose str \| None None Filter by file purpose (e.g., "batch", "fine-tune").
limit int \| None None Maximum number of results to return. Defaults to 20.
after str \| None None Pagination cursor: return results after this file ID.

DeleteResponse

Response from a delete operation.

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

CreateBatchRequest

Request to create a batch job.

Field Type Default Description
input_file_id str ID of the uploaded input file (JSONL format).
endpoint str API endpoint (e.g., "/v1/chat/completions").
completion_window str Completion window (e.g., "24h").
metadata dict\[str, Any\] \| None None Optional metadata to attach to the batch.

BatchObject

A batch job object.

Field Type Default Description
id str Unique batch ID.
object str Object type (always "batch").
endpoint str API endpoint (e.g., "/v1/chat/completions").
input_file_id str ID of the input file.
completion_window str Completion window (e.g., "24h").
status BatchStatus BatchStatus.VALIDATING Current job status.
output_file_id str \| None None ID of the output file (present when completed).
error_file_id str \| None None ID of the error file (present if some requests failed).
created_at int Unix timestamp of batch creation.
completed_at int \| None None Unix timestamp of completion (if completed).
failed_at int \| None None Unix timestamp of failure (if failed).
expired_at int \| None None Unix timestamp of expiration (if expired).
request_counts BatchRequestCounts \| None None Request processing counts.
metadata dict\[str, Any\] \| None None Metadata attached to the batch.

BatchRequestCounts

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.

BatchListResponse

Response from listing batches.

Field Type Default Description
object str Object type (always "list").
data list\[BatchObject\] \[\] List of batch objects.
has_more bool \| None None Whether more results are available.
first_id str \| None None First batch ID in the result set (for pagination).
last_id str \| None None Last batch ID in the result set (for pagination).

BatchListQuery

Query parameters for listing batches.

Field Type Default Description
limit int \| None None Maximum number of results to return. Defaults to 20.
after str \| None None Pagination cursor: return results after this batch ID.

CreateResponseRequest

Request to create a structured response.

Field Type Default Description
model str Model ID.
input dict\[str, Any\] Input data to process (e.g., a document to extract from).
instructions str \| None None Instructions for processing the input.
tools list\[ResponseTool\] \| None \[\] Available tools the model can use.
temperature float \| None None Sampling temperature in \[0.0, 2.0\]. Defaults to 1.0.
max_output_tokens int \| None None Maximum output tokens.
metadata dict\[str, Any\] \| None None Optional metadata.

ResponseTool

A tool available for the response request.

Field Type Default Description
tool_type str Tool type (e.g., "extractor", "search").
config dict\[str, Any\] Tool configuration (flattened into the object).

ResponseObject

Response from a structured response request.

Field Type Default Description
id str Unique response ID.
object str Object type (e.g., "response").
created_at int Unix timestamp of response creation.
model str Model used to generate the response.
status str Status (e.g., "succeeded", "failed").
output list\[ResponseOutputItem\] \[\] Output items from the response.
usage ResponseUsage \| None None Token usage.
error dict\[str, Any\] \| None None Error details (if status is "failed").

ResponseOutputItem

A single output item from the response.

Field Type Default Description
item_type str Output type (e.g., "text", "object", "error").
content dict\[str, Any\] Output content (flattened into the object).

ResponseUsage

Token usage for a response.

Field Type Default Description
input_tokens int Input tokens used.
output_tokens int Output tokens used.
total_tokens int Total tokens used.

WaitForBatchConfig

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
initial_interval_secs float 5 Initial interval between polls, in seconds.
max_interval_secs float 60 Maximum interval between polls (backoff plateau), in seconds.
backoff_multiplier float 1.5 Exponential backoff multiplier (e.g., 1.5 increases delay by 50% each poll).
timeout_secs float \| None None Optional timeout in seconds — polling fails if this duration is exceeded.

CustomProviderConfig

Configuration for registering a custom LLM provider at runtime.

Field Type Default Description
name str Unique name for this provider (e.g., "my-provider").
base_url str Base URL for the provider's API (e.g., <https://api.my-provider.com/v1>).
auth_header AuthHeaderFormat Authentication header format.
model_prefixes list\[str\] Model name prefixes that route to this provider (e.g., \["my-"\]).

ProviderCapabilities

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.
structured_output bool The provider supports JSON-mode or response_format structured output.
function_calling bool The provider supports tool / function calling.
audio_in bool The provider accepts audio as input.
audio_out bool The provider can generate audio / TTS output.
video_in bool The provider accepts video as input.

ProviderConfig

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 str Provider identifier (matches the entry key in providers.json).
display_name str \| None None Human-readable provider name shown in UIs.
base_url str \| None None Base URL used as the default for this provider's HTTP client.
auth AuthConfig \| None None Authentication scheme metadata (auth type + env var holding the key).
endpoints list\[str\] \| None None Supported endpoint kinds (e.g. chat, embeddings).
model_prefixes list\[str\] \| None None Model-name prefixes claimed by this provider (e.g. \["gpt-", "o1-"\]).
param_mappings dict\[str, str\] \| None None 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.

AuthConfig

Auth configuration block.

Field Type Default Description
auth_type AuthType Auth scheme classification.
env_var str \| None None Name of the environment variable that holds the API key (e.g. "OPENAI_API_KEY"). Holds the variable name, never the secret value.

BudgetConfig

Configuration for budget enforcement.

Field Type Default Description
global_limit float \| None None Maximum total spend across all models, in USD. None means unlimited.
model_limits dict\[str, float\] {} 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.

CacheConfig

Configuration for the response cache.

Field Type Default Description
max_entries 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.

RateLimitConfig

Configuration for per-model rate limits.

Field Type Default Description
rpm int \| None None Maximum requests per window. None means unlimited.
tpm int \| None None Maximum tokens per window. None means unlimited.
window float 60000ms Fixed window duration (defaults to 60 s).

Enums

AssistantContent

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(_).

Variant 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: Vec<AssistantPart>

AuthHeaderFormat

How the API key is sent in the HTTP request.

Variant Description
Bearer Bearer token: Authorization: Bearer <key>
ApiKey Custom header: e.g., X-Api-Key: <key> — Fields: _0: String
None No authentication required.

AuthType

Auth scheme used by a provider.

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

BatchStatus

Status of a batch job.

Variant Wire value Description
Validating validating Validating the input file.
Failed failed Job failed.
InProgress in_progress Job is running.
Finalizing finalizing Finalizing results.
Completed completed Job completed successfully.
Expired expired Job expired before completion.
Cancelling cancelling Job is being cancelled.
Cancelled cancelled Job has been cancelled.

CacheBackend

Storage backend for the response cache.

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

EmbeddingFormat

The format in which the embedding vectors are returned.

Variant Wire value Description
Float float 32-bit floating-point numbers (default).
Base64 base64 Base64-encoded string representation of the floats.

EmbeddingInput

Text or texts to embed.

Variant Description
Single Single text string. — Fields: _0: String
Multiple Multiple text strings (batch embedding). — Fields: _0: Vec<String>

Enforcement

How budget limits are enforced.

Variant 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.

FilePurpose

Purpose of an uploaded file.

Variant Wire value Description
Assistants assistants File for use with Assistants API.
Batch batch File for batch processing.
FineTune fine-tune File for fine-tuning.
Vision vision File for vision/image tasks.

FinishReason

Why a choice stopped generating tokens.

Variant Wire value Description
Stop stop Stop
Length length Length
ToolCalls tool_calls Tool calls
ContentFilter content_filter Content filter
FunctionCall function_call Deprecated legacy finish reason; retained for API compatibility.
Other 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.

ImageDetail

Image detail level controlling token cost and processing.

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

Message

A chat message in a conversation.

Variant Wire value Description
System system System — Fields: _0: SystemMessage
User user User — Fields: _0: UserMessage
Assistant assistant Assistant — Fields: _0: AssistantMessage
Tool tool Tool — Fields: _0: ToolMessage
Developer developer Developer — Fields: _0: DeveloperMessage
Function function Deprecated legacy function-role message; retained for API compatibility. — Fields: _0: FunctionMessage

Modality

Output modality requested from the model.

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

Variant Wire value Description
Text text Text output (the default for all providers).
Audio audio Audio / speech output.
Image image Image output (Gemini Imagen, gpt-image-1).

ModerationInput

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

Variant Description
Single Single text string. — Fields: _0: String
Multiple Multiple text strings (batch moderation). — Fields: _0: Vec<String>

OcrDocument

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

Variant Wire value Description
Url document_url A publicly accessible document URL. — Fields: url: String
Base64 base64 Inline base64-encoded document data. — Fields: data: String, media_type: String

ReasoningEffort

Controls how much reasoning effort the model should use.

Variant Wire value Description
Low low Low
Medium medium Medium
High high High

RerankDocument

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

Variant Description
Text Plain text document content. — Fields: _0: String
Object Document with explicit text field (may include metadata). — Fields: text: String

ResponseFormat

Wire format for the chat completions response_format field.

Provider mapping

  • 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.

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

StopSequence

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

Variant Description
Single Single stop sequence. — Fields: _0: String
Multiple Multiple stop sequences. — Fields: _0: Vec<String>

ToolChoice

Tool usage mode or a specific tool to call.

Variant Description
Mode Predefined mode: auto, required, or none. — Fields: _0: ToolChoiceMode
Specific Force a specific tool to be called. — Fields: _0: SpecificToolChoice

ToolType

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.

Variant Wire value Description
Function function Function

UserContent

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

Variant Description
Text Plain text content. — Fields: _0: String
Parts Array of content parts (text, images, documents, audio). — Fields: _0: Vec<ContentPart>

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