LLM Provider Overview: 30 Backends Supported by Cynative

Cynative supports 30+ LLM providers via the Bifrost SDK. Configure your provider with two environment variables or a YAML file for advanced options.

Cynative routes every LLM call through the embedded Bifrost SDK, which provides a uniform chat interface over all supported backends. This means you bring your own model (BYOM): point Cynative at any provider you already have access to — a cloud API, a managed inference endpoint, or a GPU on your desk — and Cynative adapts to it. No provider is hard-wired; the model selection is entirely yours.

Quick start

Three environment variables are all you need for the most common case:

export CYNATIVE_LLM_PROVIDER=openai           # provider id — see the catalog below
export CYNATIVE_LLM_MODEL=gpt-5               # model id string, passed verbatim to the provider
export OPENAI_API_KEY=sk-...                  # canonical API key env var (provider-specific; see table)
cynative -p "list IAM users in my AWS account that have console access"

No ~/.cynative/config.yaml file is needed for the simple path. Write YAML only when you need fields the env-var surface does not cover (e.g. extra_headers, multi-key load balancing, or advanced provider configs).

Provider catalog

Provider id	Canonical env var	Guide
openai	OPENAI_API_KEY	/providers/openai
anthropic	ANTHROPIC_API_KEY	/providers/anthropic
azure	AZURE_OPENAI_API_KEY	azure
bedrock	(AWS credential chain)	/providers/bedrock
bedrock_mantle	(AWS credential chain or api_key)	/providers/bedrock
vertex	(none — needs project_id + region)	/providers/vertex
gemini	GEMINI_API_KEY	/providers/vertex
cohere	COHERE_API_KEY	cohere
mistral	MISTRAL_API_KEY	mistral
groq	GROQ_API_KEY	groq
perplexity	PERPLEXITY_API_KEY	perplexity
cerebras	CEREBRAS_API_KEY	cerebras
openrouter	OPENROUTER_API_KEY	openrouter
xai	XAI_API_KEY	xai
huggingface	HUGGINGFACE_API_KEY	huggingface
nebius	NEBIUS_API_KEY	nebius
parasail	PARASAIL_API_KEY	parasail
fireworks	FIREWORKS_API_KEY	fireworks
replicate	REPLICATE_API_TOKEN	replicate
runware	RUNWARE_API_KEY	runware
deepseek	DEEPSEEK_API_KEY	deepseek
sarvam	SARVAM_API_KEY	sarvam
wafer	WAFER_API_KEY	wafer
databricks	DATABRICKS_TOKEN	databricks
opencode-go	OPENCODE_API_KEY	opencode-go
opencode-zen	OPENCODE_API_KEY	opencode-zen
ollama	(none — local endpoint)	/providers/local
vllm	(none — local endpoint)	/providers/local
sgl	(none — local endpoint)	/providers/local
github-copilot	(none — needs api_key + base_url)	github-copilot

Shared YAML reference

Every provider uses the same flat llm: block in ~/.cynative/config.yaml. Fields marked optional may be omitted; Cynative and Bifrost supply sensible defaults.

llm:
  provider: <provider-id>          # required — one of the ids in the catalog above
  model: <model-id>                # required — passed verbatim to the provider
  api_key: env.YOUR_KEY            # optional; falls back to the canonical env var for the provider
  reasoning_effort: high           # optional; none | minimal | low | medium | high
  reasoning_max_tokens: 2048       # optional; explicit reasoning/thinking token budget
  network_config:                  # optional; any field on Bifrost's NetworkConfig schema
    base_url: https://...                          # optional; override the provider's default endpoint
    default_request_timeout_in_seconds: 60         # optional; integer seconds (default 300)
    max_retries: 3                                 # optional; default 3 (0 disables retries)
    extra_headers:                                 # optional; map — must be set in YAML, no env form
      x-custom: value
    insecure_skip_verify: false                    # optional; skip TLS verification
  openai_config: {...}             # optional; top-level provider config (OpenAI-family options)
  azure: {...}                     # optional; per-provider identity block
  vertex: {...}                    # optional; per-provider identity block
  bedrock: {...}                   # optional; per-provider identity block
  bedrock_mantle: {...}            # optional; per-provider identity block
  vllm: {...}                      # optional; per-provider identity block
  ollama: {...}                    # optional; per-provider identity block
  sgl: {...}                       # optional; per-provider identity block
  replicate: {...}                 # optional; per-provider identity block
  databricks: {...}                # optional; per-provider identity block
  github_copilot: {...}            # optional; per-provider identity block
  keys: [...]                      # optional; advanced: multi-key load balancing

Reasoning fields are provider-portable: providers without reasoning support silently ignore them, though a model that doesn’t support reasoning may still reject the parameter upstream on providers that forward it for every model (e.g. OpenAI-style APIs). reasoning_effort maps to the provider’s native effort knob; reasoning_max_tokens sets an explicit thinking budget (Anthropic-style providers use it directly; OpenAI-style providers convert it to an estimated effort level). Gemini additionally validates an explicit budget against a per-model range at request time. Setting reasoning_effort: none together with reasoning_max_tokens is rejected at config validation.

Common environment variables

Every YAML config field is settable via a CYNATIVE_* environment variable. Maps and slices require YAML (e.g. network_config.extra_headers, keys[]). Everything else — including all identity selectors — is env-bindable.

Core selectors

Environment variable	Description
CYNATIVE_LLM_PROVIDER	Required. Provider id string (e.g. openai, anthropic).
CYNATIVE_LLM_MODEL	Required. Model id, passed verbatim to the provider.
CYNATIVE_LLM_API_KEY	Generic API key; equivalent to llm.api_key in YAML. Falls back to the provider’s canonical var if unset.

Network and timeout

Environment variable	Description
CYNATIVE_LLM_NETWORK_CONFIG_BASE_URL	Override the provider’s default API endpoint.
CYNATIVE_LLM_NETWORK_CONFIG_DEFAULT_REQUEST_TIMEOUT_IN_SECONDS	Per-request timeout in seconds (integer). Cynative default: 300.
CYNATIVE_LLM_NETWORK_CONFIG_MAX_RETRIES	Number of retry attempts. Cynative default: 3. Set to 0 to disable retries.
CYNATIVE_LLM_NETWORK_CONFIG_INSECURE_SKIP_VERIFY	Skip TLS certificate verification (true/false).

Reasoning

Environment variable	Description
CYNATIVE_LLM_REASONING_EFFORT	Reasoning effort level: none, minimal, low, medium, or high.
CYNATIVE_LLM_REASONING_MAX_TOKENS	Explicit reasoning/thinking token budget (integer).

Provider-specific identity fields

Environment variable	Provider	Description
CYNATIVE_LLM_AZURE_ENDPOINT	Azure	Azure OpenAI resource endpoint URL.
CYNATIVE_LLM_VERTEX_PROJECT_ID	Vertex	GCP project id.
CYNATIVE_LLM_VERTEX_REGION	Vertex	GCP region (e.g. us-central1).
CYNATIVE_LLM_BEDROCK_REGION	Bedrock	AWS region (e.g. us-east-1).
CYNATIVE_LLM_BEDROCK_MANTLE_REGION	Bedrock Mantle	AWS region for the Bedrock Mantle endpoint.
CYNATIVE_LLM_OLLAMA_URL	Ollama	Base URL of the Ollama server (e.g. http://localhost:11434).
CYNATIVE_LLM_VLLM_URL	vLLM	Base URL of the vLLM server (e.g. http://localhost:8000).
CYNATIVE_LLM_VLLM_MODEL_NAME	vLLM	Per-key model name for vLLM routing.
CYNATIVE_LLM_SGL_URL	SGLang	Base URL of the SGLang server (e.g. http://localhost:30000).
CYNATIVE_LLM_DATABRICKS_WORKSPACE_URL	Databricks	Databricks workspace URL.
CYNATIVE_LLM_DATABRICKS_API_FORMAT	Databricks	API format for the Databricks endpoint.
CYNATIVE_LLM_DATABRICKS_CLIENT_ID	Databricks	OAuth client id.
CYNATIVE_LLM_DATABRICKS_CLIENT_SECRET	Databricks	OAuth client secret.

Any nested Bifrost field is reachable by upper-snake-casing its JSON path: CYNATIVE_LLM_<PATH> — for example, CYNATIVE_LLM_NETWORK_CONFIG_MAX_CONNS_PER_HOST or CYNATIVE_LLM_OPENAI_CONFIG_DISABLE_STORE.

Prompt caching

Cynative always marks the stable prefix of every request with ephemeral cache breakpoints — the tool schemas, the system prompt, and the last two conversation turns.

Anthropic-family providers (anthropic, bedrock, vertex with Claude) cache that prefix and bill cached reads at a large discount. The cache window is Anthropic’s default five-minute ephemeral TTL, so back-to-back calls (e.g. --auto-approve runs) benefit most; long human-approval pauses between tool calls may let the cache expire and re-pay the write cost.

All other providers: Bifrost’s converters strip or ignore the cache markers. Providers that auto-cache server-side (OpenAI, Gemini) continue to do so regardless — Cynative’s markers don’t interfere.

There is nothing to configure. Prompt caching is on for all providers and inert where unsupported.

Bifrost exposes two additional knobs — CYNATIVE_LLM_PROMPT_CACHE_AUTO_INJECT and CYNATIVE_LLM_PROMPT_CACHE_TTL — which synthesize breakpoints for clients that emit none. Both are off by default and do nothing for Cynative, because Bifrost skips auto-injection once the caller has already marked the request, which Cynative always does.

Troubleshooting

Request timeouts

Non-streaming LLM calls default to a 300-second per-request timeout — Cynative’s default, replacing Bifrost’s 30-second default, which is too short for the long, reasoning-heavy completions a research run produces.

Override the timeout with the YAML field:

llm:
  network_config:
    default_request_timeout_in_seconds: 120   # integer seconds

Or via environment variable:

export CYNATIVE_LLM_NETWORK_CONFIG_DEFAULT_REQUEST_TIMEOUT_IN_SECONDS=120

On a timeout, the underlying error message comes from Bifrost and references default_request_timeout_in_seconds, network_config, and a “Providers > Provider Name > Network Config” UI. That wording is Bifrost’s internal copy (it even hard-codes “30 seconds” regardless of the effective timeout). Cynative has no such UI — the knob you want is network_config.default_request_timeout_in_seconds as shown above.

Rate limits and retries

LLM calls automatically retry retryable failures — HTTP 429/500/502/503/504, provider-level rate-limit errors, and transient network errors — up to 3 times with exponential backoff (500 ms initial delay, 5 s maximum). This is Cynative’s default, replacing Bifrost’s 0-retry default, under which a single rate-limit blip fails the whole turn.

Request timeouts are not retried.

Override the retry count:

llm:
  network_config:
    max_retries: 5              # integer; 0 disables retries entirely
    retry_backoff_initial: 1s   # optional; duration string
    retry_backoff_max: 10s      # optional; duration string

Or via environment variable:

export CYNATIVE_LLM_NETWORK_CONFIG_MAX_RETRIES=5

If a run still ends with a “rate limited / out of quota (HTTP 429)” error after retries, the provider account’s quota or billing limit was reached. Check your provider dashboard, or wait and retry later.