llm-proxy

LLM Proxy

LLM Proxy is a lightweight HTTP service that forwards user prompts to OpenAI's Responses API, OpenAI-compatible chat providers, Anthropic's native Messages API, Google Gemini's native generateContent API, and audio transcription APIs. It exposes protected HTTP endpoints that require a tenant secret and simplify integrating provider capabilities without embedding API credentials in each client.

Features

• Minimal HTTP server that accepts:
  • GET /?prompt=...&key=...[&provider=...] for LLM responses
  • POST /?key=...[&provider=...] for large JSON prompt bodies
  • POST /v2?key=...[&provider=...] for ordered chat-message JSON bodies
  • POST /dictate?key=...[&provider=...] for audio transcription
• Choose the provider per request via provider=...; omitted provider uses the authenticated tenant default
• Choose the model per request via model=...; omitted model uses the tenant default when provider is omitted, otherwise the selected provider's configured default
• Choose the dictation model per request via model=... on /dictate; omitted model uses the tenant default when provider is omitted, otherwise the selected provider's configured default
• Optional per-request web search via web_search=1|true|yes when the selected provider/model is configured to support it
• Optional logging at debug or info levels
• Forwards requests using server-side provider API keys
• Supports plain text, JSON, XML, or CSV responses

REST Contract

llm-proxy exposes a blocking REST contract for text generation. A caller sends one authenticated GET /, POST /, or POST /v2 request and receives the final formatted answer in that same HTTP response.

The caller does not stream tokens, poll a job endpoint, follow a resume token, or know whether the selected upstream provider uses synchronous responses, background responses, or provider-specific polling internally. For OpenAI Responses, llm-proxy always owns the background-response lifecycle: it sends stored background requests upstream and polls OpenAI server-side until the answer is terminal or server.request_timeout_seconds expires.

A 504 Gateway Timeout means the overall proxy request deadline expired before the selected upstream provider produced a final answer. It is not a prompt for the client to poll llm-proxy.

Internally, server.workers limits concurrent upstream provider HTTP operations and server.queue_size limits upstream HTTP operations waiting for a worker. Long OpenAI background-response poll sleeps do not occupy a worker slot; only the actual upstream HTTP request or poll does.

Configuration

The service reads service configuration from config.yml. The default path is config.yml in the current working directory; use --config /path/config.yml only to select a different file. Command-line flags and environment variables are not service configuration sources.

Before parsing YAML, the loader expands ${NAME} placeholders from process environment variables and from an optional .env file in the same directory as the selected config file. Process environment values override .env values. Missing placeholders fail startup except when an api_key value is exactly one missing placeholder; that exact missing provider credential expands to an empty string so non-default providers can stay disabled. The loader does not mutate process environment, and all runtime code receives only the validated config value.

server:
  port: 8080
  log_level: info
  workers: 4
  queue_size: 100
  request_timeout_seconds: 240
  max_prompt_bytes: 4194304
  max_input_audio_bytes: 26214400
tenants:
  - id: default
    secret: "${SERVICE_SECRET}"
    defaults:
      provider: openai
      model: gpt-4.1
      dictation_provider: openai
      dictation_model: gpt-4o-mini-transcribe
      system_prompt: ""
providers:
  openai:
    api_key: "${OPENAI_API_KEY}"
    base_url: "https://api.openai.com/v1"
    transcriptions_url: "https://api.openai.com/v1/audio/transcriptions"
    text:
      default_model: "gpt-4.1"
      models:
        - id: "gpt-4o-mini"
          request_profile: "openai_responses_temperature"
        - id: "gpt-4o"
          request_profile: "openai_responses_temperature_tools"
          web_search: true
        - id: "gpt-4.1"
          request_profile: "openai_responses_temperature_tools"
          web_search: true
        - id: "gpt-5-mini"
          request_profile: "openai_responses_base"
        - id: "gpt-5"
          request_profile: "openai_responses_reasoning_tools"
          web_search: true
        - id: "gpt-5.5"
          request_profile: "openai_responses_reasoning_tools"
          web_search: true
        - id: "gpt-5.5-pro"
          request_profile: "openai_responses_reasoning_tools"
          web_search: true
    dictation:
      default_model: "gpt-4o-mini-transcribe"
      models:
        - id: "gpt-4o-mini-transcribe"
        - id: "gpt-4o-transcribe"
  deepseek:
    api_key: "${DEEPSEEK_API_KEY}"
    base_url: "https://api.deepseek.com"
    text:
      default_model: "deepseek-v4-flash"
      models:
        - id: "deepseek-v4-flash"
        - id: "deepseek-v4-pro"
        - id: "deepseek-chat"
        - id: "deepseek-reasoner"
  dashscope:
    api_key: "${DASHSCOPE_API_KEY}"
    base_url: "https://dashscope-intl.aliyuncs.com/compatible-mode/v1"
    text:
      default_model: "qwen-plus"
      models:
        - id: "qwen-plus"
  moonshot:
    api_key: "${MOONSHOT_API_KEY}"
    base_url: "https://api.moonshot.ai/v1"
    text:
      default_model: "kimi-k2-0905-preview"
      models:
        - id: "kimi-k2-0905-preview"
  siliconflow:
    api_key: "${SILICONFLOW_API_KEY}"
    base_url: "https://api.siliconflow.com/v1"
    transcriptions_url: "https://api.siliconflow.com/v1/audio/transcriptions"
    text:
      default_model: "deepseek-ai/DeepSeek-R1"
      models:
        - id: "deepseek-ai/DeepSeek-R1"
    dictation:
      default_model: "FunAudioLLM/SenseVoiceSmall"
      models:
        - id: "FunAudioLLM/SenseVoiceSmall"
  zhipu:
    api_key: "${ZHIPU_API_KEY}"
    base_url: "https://open.bigmodel.cn/api/paas/v4"
    transcriptions_url: "https://api.z.ai/api/paas/v4/audio/transcriptions"
    text:
      default_model: "glm-5.1"
      models:
        - id: "glm-5.1"
    dictation:
      default_model: "glm-asr-2512"
      models:
        - id: "glm-asr-2512"
  gemini:
    api_key: "${GEMINI_API_KEY}"
    base_url: "https://generativelanguage.googleapis.com/v1"
    text:
      default_model: "gemini-2.5-flash"
      models:
        - id: "gemini-3.5-flash"
          output_token_limit: 65536
        - id: "gemini-3.1-flash-lite"
          output_token_limit: 65536
        - id: "gemini-2.5-flash"
          output_token_limit: 65536
        - id: "gemini-2.5-flash-lite"
          output_token_limit: 65536
        - id: "gemini-2.5-pro"
          output_token_limit: 65536
  anthropic:
    api_key: "${ANTHROPIC_API_KEY}"
    base_url: "https://api.anthropic.com"
    text:
      default_model: "claude-sonnet-4-6"
      models:
        - id: "claude-opus-4-8"
          output_token_limit: 128000
        - id: "claude-sonnet-4-6"
          output_token_limit: 64000
        - id: "claude-haiku-4-5-20251001"
          output_token_limit: 64000
        - id: "claude-haiku-4-5"
          output_token_limit: 64000
        - id: "claude-sonnet-4-5-20250929"
          output_token_limit: 64000
        - id: "claude-sonnet-4-5"
          output_token_limit: 64000
        - id: "claude-opus-4-1-20250805"
          output_token_limit: 32000
        - id: "claude-opus-4-1"
          output_token_limit: 32000
  grok:
    api_key: "${XAI_API_KEY}"
    base_url: "https://api.x.ai/v1"
    transcriptions_url: "https://api.x.ai/v1/stt"
    text:
      default_model: "grok-4.3"
      models:
        - id: "grok-4.3"
        - id: "grok-4.3-latest"
        - id: "grok-latest"
        - id: "grok-build-0.1"
        - id: "grok-code-fast"
        - id: "grok-code-fast-1"
        - id: "grok-code-fast-1-0825"
    dictation:
      default_model: "xai-stt"
      models:
        - id: "xai-stt"

server.workers is not the number of client requests that may be connected at once. It is the upstream provider HTTP concurrency limit shared by text generation and dictation. server.queue_size is the number of additional upstream HTTP operations that may wait for that shared limit before the proxy returns 503 request queue full.

Provider support matrix

Provider selectors and aliases are accepted anywhere the public API accepts provider. Omitted text models use the authenticated tenant default when provider is omitted; otherwise they use the selected provider's configured default text model. This table describes capabilities currently wired through llm-proxy and the defaults shipped in configs/config.yml. Upstream providers may expose additional speech APIs that need separate proxy adapters before they are available through /dictate.

Provider selector	Aliases	Text API	Configured default text model	Credential field	Default base URL	Dictation	Web search
openai	none	OpenAI Responses	gpt-4.1	providers.openai.api_key	https://api.openai.com/v1	Yes: gpt-4o-mini-transcribe, gpt-4o-transcribe	Yes, on marked OpenAI models
deepseek	none	OpenAI-compatible chat completions	deepseek-v4-flash	providers.deepseek.api_key	https://api.deepseek.com	No	No
dashscope	qwen	OpenAI-compatible chat completions	qwen-plus	providers.dashscope.api_key	https://dashscope-intl.aliyuncs.com/compatible-mode/v1	No	No
moonshot	kimi	OpenAI-compatible chat completions	kimi-k2-0905-preview	providers.moonshot.api_key	https://api.moonshot.ai/v1	No	No
siliconflow	none	OpenAI-compatible chat completions	deepseek-ai/DeepSeek-R1	providers.siliconflow.api_key	https://api.siliconflow.com/v1	Yes: FunAudioLLM/SenseVoiceSmall	No
zhipu	glm	OpenAI-compatible chat completions	glm-5.1	providers.zhipu.api_key	https://open.bigmodel.cn/api/paas/v4	Yes: glm-asr-2512	No
gemini	none	Gemini native generateContent	gemini-2.5-flash	providers.gemini.api_key	https://generativelanguage.googleapis.com/v1	No	No
anthropic	claude	Anthropic native Messages	claude-sonnet-4-6	providers.anthropic.api_key	https://api.anthropic.com	No	No
grok	xai	xAI OpenAI-compatible chat completions	grok-4.3	providers.grok.api_key	https://api.x.ai/v1	Yes: xai-stt	No

All upstream provider credentials are server-side only. Client requests must never send OpenAI, Anthropic, xAI, Gemini, or other upstream API keys.

Model catalog schema

Model ids and per-model metadata are runtime config data. To add, remove, or replace provider models, update the selected config.yml and restart the service; provider transports stay code-owned.

Each provider must declare a text catalog. A provider with an api_key configured must have a valid text default_model; that default is used when a request selects the provider and omits model.

providers:
  provider_name:
    text:
      default_model: "provider-default-model"
      models:
        - id: "provider-model-id"
          request_profile: "openai_responses_temperature_tools"
          web_search: true
          output_token_limit: 65536

Dictation-capable providers must also declare a dictation catalog:

providers:
  provider_name:
    dictation:
      default_model: "provider-default-dictation-model"
      models:
        - id: "provider-dictation-model-id"

Catalog validation fails startup when a provider text catalog is missing, a dictation-capable provider dictation catalog is missing, a model id is blank or duplicated, default_model is not present in the corresponding models list, or web_search: true appears outside an OpenAI text model entry. output_token_limit is optional for most providers; when set, it is used as a proxy-side maximum for max_tokens. Anthropic text models require output_token_limit because Anthropic Messages requires max_tokens even when the client omits it.

request_profile is currently required only for OpenAI text models. It selects the stable proxy payload shape for that OpenAI model and must be one of:

Request profile	Payload behavior
openai_responses_base	Sends model and input; omits temperature, tools, and reasoning controls.
openai_responses_temperature	Adds temperature.
openai_responses_temperature_tools	Adds temperature; includes web-search tools only when both the request and model catalog enable web search.
openai_responses_reasoning_tools	Adds reasoning/text controls; includes web-search tools only when both the request and model catalog enable web search.

All OpenAI Responses text requests also send background: true and store: true. llm-proxy polls the stored OpenAI response server-side until it reaches a terminal state or the normal server.request_timeout_seconds deadline expires. Plain REST callers use one GET /, POST /, or POST /v2 request and receive the final formatted answer; they do not stream, poll, or follow a separate resume endpoint.

Provider-specific details:

• OpenAI is the only provider currently exposed with web_search support, and only for OpenAI model catalog entries with web_search: true. OpenAI dictation uses the same providers.openai.api_key value. OpenAI Responses and Models endpoint URLs are derived from providers.openai.base_url; dictation uses providers.openai.transcriptions_url.
• OpenAI-compatible text providers send chat completion requests with Authorization: Bearer <api_key> and the selected provider base URL.
• Only dictation-capable providers expose transcriptions_url fields: OpenAI uses providers.openai.transcriptions_url, SiliconFlow uses providers.siliconflow.transcriptions_url, Zhipu uses providers.zhipu.transcriptions_url, and Grok/xAI uses providers.grok.transcriptions_url.
• Gemini text requests use the native generateContent route and normalize Gemini usage metadata into the same response headers and JSON usage object used by the other text providers.
• Anthropic text requests use POST /v1/messages with x-api-key and anthropic-version: 2023-06-01. System messages are translated to Anthropic's top-level system field. Anthropic requires max_tokens, so when the client omits it the proxy sends the selected Claude model's configured output limit.
• Zhipu dictation uses Z.AI GLM-ASR through providers.zhipu.transcriptions_url with the selected configured dictation model.
• Grok text requests use xAI's OpenAI-compatible /chat/completions API at https://api.x.ai/v1. Grok/xAI dictation uses xAI STT through providers.grok.transcriptions_url; the upstream STT endpoint does not receive a model multipart field.

Provider API keys are optional until a tenant uses that provider as a default. If a non-default provider key is blank or its whole api_key value is a missing ${...} placeholder, startup continues and explicit requests for that provider return 503 provider not configured. Missing placeholders in other fields, or embedded inside a longer api_key value, fail startup. If a tenant's default text or dictation provider lacks its API key, startup fails before the server listens. Provider base_url values are explicit config values; leave them at the documented URLs unless routing through a test server, proxy, or compatible gateway. Dictation-capable provider transcriptions_url values are also explicit config values and are required for OpenAI, SiliconFlow, Zhipu, and Grok/xAI. Text model catalogs are required for every supported provider, and dictation model catalogs are required for OpenAI, SiliconFlow, Zhipu, and Grok/xAI. Startup validates that tenants includes at least one unique id and unique secret, then validates each tenant's default text provider/model and dictation provider/model against those configured catalogs and credentials. Unknown YAML keys fail startup.

Web search is per request and currently supported only on OpenAI models that support the OpenAI web search tool. Text output length is also per request: pass max_tokens when a client wants to cap one generation. When omitted, the proxy does not send a provider max-token field, except Anthropic Messages where max_tokens is required upstream and the proxy sends the selected model's configured output limit. Provider-specific output-token limits are enforced at the request edge when known. Gemini text models currently reject max_tokens above 65536; Claude models reject values above the configured synchronous Messages output limit. Those errors return 400 Bad Request before any upstream provider call.

Running

Generate a secret:

openssl rand -hex 32

Run the service with OpenAI defaults:

./llm-proxy --config config.yml

In the full config.yml, set a tenant's default text provider/model to route omitted-provider requests to DeepSeek:

tenants:
  - id: deepseek
    secret: "${SERVICE_SECRET}"
    defaults:
      provider: deepseek
      model: deepseek-v4-flash

Set Gemini as the default text provider:

tenants:
  - id: gemini
    secret: "${SERVICE_SECRET}"
    defaults:
      provider: gemini
      model: gemini-2.5-flash

Set Anthropic as the default text provider:

tenants:
  - id: anthropic
    secret: "${SERVICE_SECRET}"
    defaults:
      provider: anthropic
      model: claude-sonnet-4-6

Set Grok as the default text provider:

tenants:
  - id: grok
    secret: "${SERVICE_SECRET}"
    defaults:
      provider: grok
      model: grok-4.3

Local Automation

This repository exposes the standard local targets used by MPR app repos:

Command	Purpose
make ci	Run format checks, Go lint (go vet, staticcheck, ineffassign), Python strict mypy, the 100% coverage-gated Go test suite, and Python pytest.
make test-live-providers	Generate a complete temporary config and run live text smoke tests for every provider whose API key is present; use LIVE_ENV_FILE=/path/to/env to load interpolation values.
make test-live-gemini	Compatibility wrapper for make test-live-providers with LLM_PROXY_LIVE_PROVIDERS=gemini.
make release	Cut a v* release from master, update CHANGELOG.md when needed, and push the release tag.
make publish	Validate the release source and publish ghcr.io/tyemirov/llm-proxy:<tag> plus :latest.
make deploy	Verify the published image and deploy through the sibling ../mprlab-gateway checkout.

Live provider smoke tests are intentionally not part of make ci; they call paid upstream APIs and depend on local or CI secret availability. The dynamic target discovers these provider keys after loading LIVE_ENV_FILE. By default, smoke requests omit model, so each provider uses the default configured in the selected configs/config.yml; set a model override only when debugging a specific provider/model pair.

Provider	Key variable	Model override
OpenAI	OPENAI_API_KEY	LLM_PROXY_LIVE_OPENAI_MODEL
DeepSeek	DEEPSEEK_API_KEY	LLM_PROXY_LIVE_DEEPSEEK_MODEL
DashScope/Qwen	DASHSCOPE_API_KEY	LLM_PROXY_LIVE_DASHSCOPE_MODEL
Moonshot/Kimi	MOONSHOT_API_KEY	LLM_PROXY_LIVE_MOONSHOT_MODEL
SiliconFlow	SILICONFLOW_API_KEY	LLM_PROXY_LIVE_SILICONFLOW_MODEL
Zhipu/GLM	ZHIPU_API_KEY	LLM_PROXY_LIVE_ZHIPU_MODEL
Gemini	GEMINI_API_KEY	LLM_PROXY_LIVE_GEMINI_MODEL
Anthropic/Claude	ANTHROPIC_API_KEY	LLM_PROXY_LIVE_ANTHROPIC_MODEL
Grok/xAI	XAI_API_KEY	LLM_PROXY_LIVE_GROK_MODEL

Run every provider with an available key:

make test-live-providers LIVE_ENV_FILE=configs/.env

Run only selected providers. When LLM_PROXY_LIVE_PROVIDERS is set, every listed provider must have its key:

LLM_PROXY_LIVE_PROVIDERS=openai,gemini \
  make test-live-providers LIVE_ENV_FILE=configs/.env

The release lifecycle commands wrap their local make ci gate with the standard 350-second timeout by default. For exceptional local diagnostics, override all three with LLM_PROXY_CI_TIMEOUT_SECONDS=<seconds>, or use the command-specific RELEASE_CI_TIMEOUT_SECONDS, PUBLISH_CI_TIMEOUT_SECONDS, and DEPLOY_CI_TIMEOUT_SECONDS variables.

llm-proxy is a gateway-local service in mprlab-gateway, so make deploy defaults to the gateway deploy-gateway target. Override the checkout or target with GATEWAY_DIR=/path/to/mprlab-gateway or GATEWAY_DEPLOY_TARGET=<target>.

Usage

Installable prompt client

Install the reusable JSON POST client:

go install github.com/tyemirov/llm-proxy/llm-proxy-client@latest

Use it with explicit flags:

llm-proxy-client \
  --base-url "http://localhost:8080/?provider=gemini" \
  --secret "$SERVICE_SECRET" \
  --model gemini-2.5-flash \
  --prompt "Summarize this"

Or read configuration and prompt text from environment/stdin:

export LLM_PROXY_BASE_URL="http://localhost:8080/"
export LLM_PROXY_SECRET="$SERVICE_SECRET"
printf 'large prompt...\n' | llm-proxy-client --model gpt-5.5 --max-tokens 4096

The client always uses canonical POST /v2?key=... with a JSON body. It keeps non-payload query parameters such as provider, strips body-owned query fields such as prompt and model, and sends the prompt as a v2 user message. --system-prompt becomes a v2 system message. Optional model, web_search, and max_tokens values remain body fields. When --model is omitted, the body omits model so llm-proxy uses the selected provider's configured default model.

The reusable Go package under pkg/llmproxyclient is v2-only: construct a MessagesRequest with NewMessagesRequest and send it with Client.PostMessages.

Python client package

The same transport contract is available as an importable Python package:

uv pip install "llm-proxy-client @ git+https://github.com/tyemirov/llm-proxy.git"

from llm_proxy_client import Client, ClientConfig, ClientMessagesRequest, ClientMessage

client = Client(
    ClientConfig(
        base_url="http://localhost:8080/?provider=gemini",
        secret="mysecret",
    )
)

text = client.post_messages(
    ClientMessagesRequest(
        messages=(ClientMessage(role="user", content="Summarize this"),),
        model="gemini-2.5-flash",
        max_tokens=512,
    )
)

The Python package is v2-only. For chat-transcript callers, send the same post_messages request with multiple messages:

chat_text = client.post_messages(
    ClientMessagesRequest(
        messages=(
            ClientMessage(role="user", content="Summarize this", order=2),
            ClientMessage(role="system", content="Be concise.", order=1),
        ),
        model="deepseek-v4-flash",
    )
)

The optional order field is for callers that do not want to rely on array position. When any message includes order, every submitted message must include a unique non-negative integer order; the proxy sorts ascending before provider routing and echoes provided order values in JSON responses.

For local development:

uv pip install -e .
make python-test
make python-lint

Basic request (default provider and model, no web search)

curl --get \
  --data-urlencode "prompt=Hello, how are you?" \
  --data-urlencode "key=mysecret" \
  "http://localhost:8080/"

Choose a provider

curl --get \
  --data-urlencode "prompt=Summarize this cheaply" \
  --data-urlencode "key=mysecret" \
  --data-urlencode "provider=deepseek" \
  --data-urlencode "model=deepseek-v4-flash" \
  "http://localhost:8080/"

Gemini text generation:

curl --get \
  --data-urlencode "prompt=Summarize this with Gemini" \
  --data-urlencode "key=mysecret" \
  --data-urlencode "provider=gemini" \
  --data-urlencode "model=gemini-2.5-flash" \
  --data-urlencode "max_tokens=512" \
  "http://localhost:8080/"

Anthropic Claude text generation:

curl --get \
  --data-urlencode "prompt=Summarize this with Claude" \
  --data-urlencode "key=mysecret" \
  --data-urlencode "provider=anthropic" \
  --data-urlencode "model=claude-sonnet-4-6" \
  --data-urlencode "max_tokens=512" \
  "http://localhost:8080/"

Grok text generation:

curl --get \
  --data-urlencode "prompt=Summarize this with Grok" \
  --data-urlencode "key=mysecret" \
  --data-urlencode "provider=grok" \
  --data-urlencode "model=grok-4.3" \
  --data-urlencode "max_tokens=512" \
  "http://localhost:8080/"

Large text request

Use POST / with a JSON body when the prompt is too large for a URL query parameter or when the caller already has a chat transcript. Authentication still uses the key query parameter, which is the configured tenant secret. Provider selection also stays in the query parameter. Do not send upstream provider secrets in the request body; the proxy reads them from server-side configuration. The JSON body is capped by server.max_prompt_bytes.

curl -X POST \
  -H "Content-Type: application/json" \
  --data '{"prompt":"large text...","model":"gpt-5.5","web_search":false,"system_prompt":"optional","max_tokens":4096}' \
  "http://localhost:8080/?key=mysecret"

Compatibility chat transcript on /:

curl -X POST \
  -H "Content-Type: application/json" \
  --data '{"messages":[{"role":"user","content":"Summarize this","order":2},{"role":"system","content":"Be concise.","order":1}],"model":"deepseek-v4-flash","max_tokens":4096}' \
  "http://localhost:8080/?key=mysecret&provider=deepseek"

Canonical v2 chat transcript:

curl -X POST \
  -H "Content-Type: application/json" \
  --data '{"messages":[{"role":"user","content":"Summarize this","order":2},{"role":"system","content":"Be concise.","order":1}],"model":"deepseek-v4-flash","max_tokens":4096}' \
  "http://localhost:8080/v2?key=mysecret&provider=deepseek"

JSON body fields:

Field	Required	Default	Description
prompt	Yes, unless messages is provided	none	Full text to send to the LLM. Use this body field for large or non-ASCII prompts.
messages	Yes, unless prompt is provided	none	Chat messages using role and string content. Supported roles are system, user, and assistant; at least one user message is required. Each item may include numeric order; if any item includes it, every submitted item must include a unique non-negative order, and messages are sorted ascending before routing.
model	No	tenant or configured provider default	Model identifier from the selected provider's configured model list. Omitted model uses the tenant default when provider is omitted; otherwise it uses the selected provider's configured default.
web_search	No	false	Enables OpenAI web search when the selected provider/model supports it.
system_prompt	No	authenticated tenant default	Per-request system prompt override. With messages, it is prepended as a system message only when the body does not already contain a system message.
max_tokens	No	provider default	Positive integer output-token cap for this request. The proxy maps it to OpenAI max_output_tokens, OpenAI-compatible max_tokens, Anthropic max_tokens, or Gemini generationConfig.maxOutputTokens.

For POST /, provider remains a query parameter. Query model may override the JSON body only when the body omits model or provides the same value; conflicting values return 400 Bad Request. Bodies that provide both prompt and messages, empty messages, unsupported message roles, empty message content, partially specified order, duplicate or negative order, or both system_prompt and a system message return 400 Bad Request before any upstream call. Gemini max_tokens values above 65536 return 400 Bad Request before the proxy calls Gemini. Anthropic max_tokens values above the configured Claude model output limit return 400 Bad Request before the proxy calls Anthropic.

POST /v2 is the canonical chat endpoint. It accepts the same messages, model, web_search, and max_tokens body fields, but rejects prompt and body system_prompt; send a system role message instead. The tenant default system prompt is still prepended when the submitted messages do not include a system message.

Choose an OpenAI model

curl --get \
  --data-urlencode "prompt=Summarize quantum error correction" \
  --data-urlencode "key=mysecret" \
  --data-urlencode "model=gpt-4o" \
  "http://localhost:8080/"

Enable web search

curl --get \
  --data-urlencode "prompt=What changed in the 2025 child tax credit?" \
  --data-urlencode "key=mysecret" \
  --data-urlencode "web_search=1" \
  "http://localhost:8080/"

You can enable web search with GPT-5 by specifying the model:

curl --get \
  --data-urlencode "prompt=Latest research on quantum gravity" \
  --data-urlencode "key=mysecret" \
  --data-urlencode "model=gpt-5" \
  --data-urlencode "web_search=1" \
  "http://localhost:8080/"

Dictation request

curl -X POST \
  -F "audio=@./recording.webm" \
  "http://localhost:8080/dictate?key=mysecret"

SiliconFlow dictation:

curl -X POST \
  -F "audio=@./recording.webm" \
  "http://localhost:8080/dictate?key=mysecret&provider=siliconflow"

Optional model override:

curl -X POST \
  -F "audio=@./recording.webm" \
  "http://localhost:8080/dictate?key=mysecret&model=gpt-4o-mini-transcribe"

Response formats

You can request alternative formats using either the format query parameter or the Accept header. Supported values are:

• text/csv - the reply as a single CSV cell with internal quotes doubled and a trailing newline
• application/json - JSON object containing request and response fields, plus usage when upstream token usage is available
• application/xml - XML document <response request="...">...</response>

If no supported value is provided, text/plain is returned.

When upstream text providers return token usage, the proxy also sets these response headers without changing the plain text, XML, or CSV response bodies:

Header	Description
X-LLM-Proxy-Request-Tokens	Normalized request/input token count
X-LLM-Proxy-Response-Tokens	Normalized response/output token count
X-LLM-Proxy-Total-Tokens	Normalized total token count

JSON-format LLM responses include the same normalized counts:

{
  "request": "Hello",
  "response": "Hi",
  "object": "chat.completion",
  "model": "gpt-4.1",
  "choices": [
    {
      "index": 0,
      "finish_reason": "stop",
      "message": {
        "role": "assistant",
        "content": "Hi"
      }
    }
  ],
  "messages": [
    {
      "role": "user",
      "content": "Hello"
    }
  ],
  "usage": {
    "request_tokens": 1,
    "response_tokens": 1,
    "total_tokens": 2
  }
}

The response messages field echoes only caller-visible request messages. Server-injected tenant default system prompts are sent upstream when applicable, but are not returned in response metadata.

Endpoint

LLM endpoint

GET /
  ?prompt=STRING            # required
  &key=SERVICE_SECRET       # required
  &provider=PROVIDER        # optional; tenant default
  &model=MODEL_NAME         # optional; tenant or configured provider default
  &web_search=1|true|yes    # optional; requires configured model support
  &max_tokens=N             # optional positive integer per-request cap
  &format=CONTENT_TYPE      # optional; or use Accept header

POST /
  ?key=SERVICE_SECRET       # required
  &provider=PROVIDER        # optional; tenant default
  &model=MODEL_NAME         # optional; overrides JSON body if absent or equal
  &format=CONTENT_TYPE      # optional; or use Accept header
Content-Type: application/json
{
  "prompt": "STRING",       # required unless messages is provided
  "messages": [             # required unless prompt is provided
    {"role": "user", "content": "STRING", "order": 1}
  ],
  "model": "MODEL_NAME",    # optional; tenant or configured provider default
  "web_search": false,      # optional; defaults to false
  "system_prompt": "STRING",# optional; tenant default
  "max_tokens": 512         # optional positive integer per-request cap
}

POST /v2
  ?key=SERVICE_SECRET       # required
  &provider=PROVIDER        # optional; tenant default
  &model=MODEL_NAME         # optional; overrides JSON body if absent or equal
  &format=CONTENT_TYPE      # optional; or use Accept header
Content-Type: application/json
{
  "messages": [             # required
    {"role": "user", "content": "STRING", "order": 1}
  ],
  "model": "MODEL_NAME",    # optional; tenant or configured provider default
  "web_search": false,      # optional; defaults to false
  "max_tokens": 512         # optional positive integer per-request cap
}

The POST JSON body carries only LLM request parameters. The tenant secret remains in the key query parameter, and upstream provider API keys are never accepted from client requests.

Dictation endpoint

POST /dictate
  ?key=SERVICE_SECRET       # required
  &provider=PROVIDER        # optional; tenant default
  &model=MODEL_NAME         # optional; tenant or configured provider default
Content-Type: multipart/form-data
  audio=<file>              # required (alias: file)

Success response:

{ "text": "..." }

The default model catalog in configs/config.yml declares the LLM endpoint models below. The /dictate endpoint defaults to OpenAI's audio transcriptions API and also supports SiliconFlow, Zhipu, and Grok/xAI through their provider selectors. Not all configured models support tools; use a model marked Yes below for web search. A dash in the proxy max_tokens limit column means the proxy validates only that max_tokens is positive and lets the upstream provider enforce any provider-side model limit.

Model capabilities

Model	Provider	Provider default	Proxy max_tokens limit	Web search
gpt-4.1	OpenAI	Yes	-	Yes
gpt-4o	OpenAI	No	-	Yes
gpt-4o-mini	OpenAI	No	-	No
gpt-5	OpenAI	No	-	Yes
gpt-5-mini	OpenAI	No	-	No
gpt-5.5	OpenAI	No	-	Yes
gpt-5.5-pro	OpenAI	No	-	Yes
deepseek-v4-flash	DeepSeek	Yes	-	No
deepseek-v4-pro	DeepSeek	No	-	No
deepseek-chat	DeepSeek	No	-	No
deepseek-reasoner	DeepSeek	No	-	No
qwen-plus	DashScope/Qwen	Yes	-	No
kimi-k2-0905-preview	Moonshot/Kimi	Yes	-	No
deepseek-ai/DeepSeek-R1	SiliconFlow	Yes	-	No
glm-5.1	Zhipu/GLM	Yes	-	No
gemini-3.5-flash	Gemini	No	65536	No
gemini-3.1-flash-lite	Gemini	No	65536	No
gemini-2.5-flash	Gemini	Yes	65536	No
gemini-2.5-flash-lite	Gemini	No	65536	No
gemini-2.5-pro	Gemini	No	65536	No
claude-opus-4-8	Anthropic/Claude	No	128000	No
claude-sonnet-4-6	Anthropic/Claude	Yes	64000	No
claude-haiku-4-5-20251001	Anthropic/Claude	No	64000	No
claude-haiku-4-5	Anthropic/Claude	No	64000	No
claude-sonnet-4-5-20250929	Anthropic/Claude	No	64000	No
claude-sonnet-4-5	Anthropic/Claude	No	64000	No
claude-opus-4-1-20250805	Anthropic/Claude	No	32000	No
claude-opus-4-1	Anthropic/Claude	No	32000	No
grok-4.3	Grok/xAI	Yes	-	No
grok-4.3-latest	Grok/xAI	No	-	No
grok-latest	Grok/xAI	No	-	No
grok-build-0.1	Grok/xAI	No	-	No
grok-code-fast	Grok/xAI	No	-	No
grok-code-fast-1	Grok/xAI	No	-	No
grok-code-fast-1-0825	Grok/xAI	No	-	No

Dictation capabilities

Provider selector	Models	Credential field	Transcription URL field	Notes
openai	gpt-4o-mini-transcribe, gpt-4o-transcribe	providers.openai.api_key	providers.openai.transcriptions_url	Default dictation provider and default model gpt-4o-mini-transcribe.
siliconflow	FunAudioLLM/SenseVoiceSmall	providers.siliconflow.api_key	providers.siliconflow.transcriptions_url	OpenAI-compatible audio transcription.
zhipu / glm	glm-asr-2512	providers.zhipu.api_key	providers.zhipu.transcriptions_url	Z.AI GLM-ASR; sends model=glm-asr-2512.
grok / xai	xai-stt	providers.grok.api_key	providers.grok.transcriptions_url	xAI STT; the proxy model name selects the provider but is not sent as a multipart model field.

Status codes

• 200 OK - success
• 400 Bad Request - missing/invalid parameters, invalid multipart audio form, unknown provider/model, or unsupported provider capability
• 403 Forbidden - missing or invalid key
• 413 Payload Too Large - JSON prompt body exceeds max_prompt_bytes
• 429 Too Many Requests - upstream provider rate limit
• 503 Service Unavailable - selected provider credential is unavailable because that non-default provider is disabled or missing its API key
• 504 Gateway Timeout - the overall proxy request timed out before the selected upstream provider returned a final result
• 502 Bad Gateway - upstream provider API returned an error

Security

• All requests must include a configured tenant secret via key=....
• Client requests must not include upstream provider API keys; configure them on the server.
• Do not expose this service to the public internet without appropriate network controls.

Implementation Plans

Current scoped implementation plans are tracked under docs/implementation/.

MPR Integration Verification

For Marco Polo Research Lab integration workflows, use the Codex mpr-integration skill when a change needs contract/profile/task-based black-box verification against an MPR app or fixture. Keep app-specific hostnames, cookie names, ports, OAuth callbacks, and environment literals in the selected integration profile or deployment docs, not in this README.

Releasing

Use make release from a clean, up-to-date master branch. It runs make ci, updates CHANGELOG.md if the selected version is missing, creates the release commit when needed, and pushes the v* tag. Tags that begin with v trigger the release workflow, which builds and publishes release artifacts and uses the matching changelog section as release notes.

Use make publish only when you need to publish the release image manually. Use make deploy after the release image is published and :latest points at the same digest as the release tag.

License

This project is licensed under the MIT License. See LICENSE for details.