Providers and Models

Use this page when the first reply fails because of provider/model mismatch, or when you want to adapt the concrete setup example to a different provider. If you already know which provider you want and only need a pasteable setup, use provider-cookbook.md.

For every setup, answer three questions:

Which provider owns the credential or endpoint?
What model name does that provider expect?
Does the provider need apiKey, apiBase, OAuth login, cloud credentials, or only a local server URL?

Prefer a named modelPresets entry for the model/provider pair, then select it with agents.defaults.modelPreset. Direct agents.defaults.provider and agents.defaults.model still work for existing configs, but presets make runtime /model switching and fallback chains clearer. Pin provider inside the preset while setting up; you can switch back to "auto" later.

Choose a Provider Without Guessing

The docs show concrete provider names so the JSON is copyable, not because nanobot ranks providers. Start from the service or endpoint you actually control:

If you have...	Configure...
An API key from a hosted provider or gateway	That provider's `providers.<name>.apiKey`, then a preset with that provider name and a model ID from that service.
A company proxy or regional endpoint	The matching provider block plus `apiBase` if the proxy gives you a URL.
A local OpenAI-compatible server	A local provider block such as `ollama`, `vllm`, `lmStudio`, or `custom`, usually with `apiBase`.
An OAuth-based account	Run the matching `nanobot provider login ...` command, then select that provider explicitly in a preset.
No provider yet	Pick one outside nanobot based on account access, pricing, regional availability, privacy requirements, and the model IDs you need. Then come back with its key and model ID.

Minimal Shape

{
  "providers": {
    "openrouter": {
      "apiKey": "sk-or-v1-xxx"
    }
  },
  "modelPresets": {
    "primary": {
      "provider": "openrouter",
      "model": "anthropic/claude-opus-4.5",
      "maxTokens": 8192,
      "contextWindowTokens": 65536,
      "temperature": 0.1
    }
  },
  "agents": {
    "defaults": {
      "modelPreset": "primary"
    }
  }
}

The provider config gives nanobot credentials and endpoint details. The model preset names the provider/model pair. The agent defaults choose which named preset to use for normal turns. Replace the example provider and model together; mixing an API key from one provider with a model ID from another is the most common first-run failure.

Provider, Model, API Key, and Base URL

These fields answer different questions:

Field	Where it lives	Meaning
`provider`	`modelPresets.<name>.provider`	Which nanobot provider adapter should send the request.
`model`	`modelPresets.<name>.model`	The model ID expected by that provider or gateway.
`apiKey`	`providers.<provider>.apiKey`	Credential for that provider. Use `${ENV_VAR}` for secrets.
`apiBase`	`providers.<provider>.apiBase`	HTTP base URL of the provider endpoint.

You usually omit apiBase for hosted built-in providers such as OpenRouter, Anthropic direct, OpenAI direct, Groq, or Bedrock because nanobot knows their default endpoints. Set apiBase for custom, local OpenAI-compatible servers, provider proxies, regional endpoints, or subscription endpoints. Include the API version path when the endpoint requires it, for example https://api.example.com/v1 or http://localhost:11434/v1.

Common Provider Patterns

OpenRouter Gateway

Gateway-style setup for model IDs served through OpenRouter.

{
  "providers": {
    "openrouter": {
      "apiKey": "${OPENROUTER_API_KEY}"
    }
  },
  "modelPresets": {
    "primary": {
      "provider": "openrouter",
      "model": "anthropic/claude-opus-4.5",
      "maxTokens": 8192,
      "contextWindowTokens": 65536
    }
  },
  "agents": {
    "defaults": {
      "modelPreset": "primary"
    }
  }
}

Use the model ID exactly as OpenRouter lists it.

Anthropic Direct

{
  "providers": {
    "anthropic": {
      "apiKey": "${ANTHROPIC_API_KEY}"
    }
  },
  "modelPresets": {
    "primary": {
      "provider": "anthropic",
      "model": "claude-opus-4-5",
      "maxTokens": 8192,
      "contextWindowTokens": 200000
    }
  },
  "agents": {
    "defaults": {
      "modelPreset": "primary"
    }
  }
}

Anthropic direct uses the native Anthropic provider. Do not use an OpenRouter model ID unless the provider is OpenRouter.

If you use an Anthropic-compatible proxy, keep the provider as anthropic and override apiBase:

{
  "providers": {
    "anthropic": {
      "apiKey": "${ANTHROPIC_API_KEY}",
      "apiBase": "https://anthropic-proxy.example.com"
    }
  },
  "modelPresets": {
    "primary": {
      "provider": "anthropic",
      "model": "claude-sonnet-4-5"
    }
  }
}

Arbitrary custom provider names are OpenAI-compatible only; they do not use the Anthropic Messages API request format.

OpenAI Direct

{
  "providers": {
    "openai": {
      "apiKey": "${OPENAI_API_KEY}"
    }
  },
  "modelPresets": {
    "primary": {
      "provider": "openai",
      "model": "gpt-5",
      "maxTokens": 8192,
      "contextWindowTokens": 128000
    }
  },
  "agents": {
    "defaults": {
      "modelPreset": "primary"
    }
  }
}

providers.openai.apiType may be set when you need to force a specific OpenAI API surface. Other providers reject apiType; leave it unset outside providers.openai. Replace the model with a model ID available to your OpenAI account.

Custom OpenAI-Compatible Endpoint

The custom provider fits one OpenAI-compatible endpoint that is not represented by a named provider.

{
  "providers": {
    "custom": {
      "apiKey": "${CUSTOM_API_KEY}",
      "apiBase": "https://example.com/v1"
    }
  },
  "modelPresets": {
    "primary": {
      "provider": "custom",
      "model": "provider-model-name",
      "maxTokens": 8192,
      "contextWindowTokens": 65536
    }
  },
  "agents": {
    "defaults": {
      "modelPreset": "primary"
    }
  }
}

custom does not infer a default base URL. Set apiBase.

If you have more than one custom OpenAI-compatible endpoint, give each endpoint its own provider key under providers and use that same key in the model preset. The key can be a name that makes sense in your environment, such as companyProxy, tenant-a, or dev-local.

{
  "providers": {
    "companyProxy": {
      "apiKey": "${COMPANY_PROXY_API_KEY}",
      "apiBase": "https://llm-proxy.example.com/v1"
    },
    "tenant-a": {
      "apiBase": "https://tenant-a.example.com/v1"
    }
  },
  "modelPresets": {
    "company": {
      "provider": "companyProxy",
      "model": "gpt-4o-mini",
      "maxTokens": 8192,
      "contextWindowTokens": 65536
    },
    "tenantA": {
      "provider": "tenant-a",
      "model": "served-model-name",
      "maxTokens": 8192,
      "contextWindowTokens": 65536
    }
  },
  "agents": {
    "defaults": {
      "modelPreset": "company"
    }
  }
}

Custom provider keys are treated as direct OpenAI-compatible providers. apiBase is required because nanobot cannot know the endpoint URL. apiKey is optional for local servers or private proxies that do not require one. Choose a name that does not conflict with a built-in provider name or alias, such as openai, openai-codex, github-copilot, or lm-studio. Do not set apiType on custom provider keys; apiType is only for providers.openai.

This named custom provider path is not for Anthropic-compatible endpoints. For Anthropic-compatible proxies, use providers.anthropic.apiBase and set the preset provider to anthropic.

Ollama

Start Ollama separately, then point nanobot at the OpenAI-compatible endpoint.

{
  "providers": {
    "ollama": {
      "apiBase": "http://localhost:11434/v1"
    }
  },
  "modelPresets": {
    "primary": {
      "provider": "ollama",
      "model": "llama3.2",
      "maxTokens": 4096,
      "contextWindowTokens": 32768
    }
  },
  "agents": {
    "defaults": {
      "modelPreset": "primary"
    }
  }
}

Most Ollama setups do not require an API key.

vLLM or Other Local OpenAI-Compatible Server

{
  "providers": {
    "vllm": {
      "apiBase": "http://127.0.0.1:8000/v1",
      "apiKey": "EMPTY"
    }
  },
  "modelPresets": {
    "primary": {
      "provider": "vllm",
      "model": "served-model-name",
      "maxTokens": 8192,
      "contextWindowTokens": 65536
    }
  },
  "agents": {
    "defaults": {
      "modelPreset": "primary"
    }
  }
}

Some OpenAI-compatible local servers require any non-empty API key even when they do not validate it.

LM Studio

{
  "providers": {
    "lmStudio": {
      "apiBase": "http://localhost:1234/v1"
    }
  },
  "modelPresets": {
    "primary": {
      "provider": "lm_studio",
      "model": "local-model",
      "maxTokens": 4096,
      "contextWindowTokens": 32768
    }
  },
  "agents": {
    "defaults": {
      "modelPreset": "primary"
    }
  }
}

Config keys may be camelCase or snake_case. Provider names in model presets should use the registry name, such as lm_studio.

AWS Bedrock

Bedrock can use the AWS credential chain, profile, region, or Bedrock bearer token depending on your AWS setup.

{
  "providers": {
    "bedrock": {
      "region": "us-east-1",
      "profile": "default"
    }
  },
  "modelPresets": {
    "primary": {
      "provider": "bedrock",
      "model": "bedrock/anthropic.claude-sonnet-4-5-20250929-v1:0",
      "maxTokens": 8192,
      "contextWindowTokens": 200000
    }
  },
  "agents": {
    "defaults": {
      "modelPreset": "primary"
    }
  }
}

See configuration.md#providers for Bedrock-specific notes.

OAuth Providers

Some providers do not use API keys in config.json.

nanobot provider login openai-codex
nanobot provider login github-copilot

Then explicitly select the provider and model in a preset. OAuth providers are not valid automatic fallbacks.

Provider Resolution

The recommended path is a named preset selected by agents.defaults.modelPreset. The effective model parameters come from:

the named modelPresets entry referenced by agents.defaults.modelPreset;
otherwise the implicit default preset built from agents.defaults.model, provider, maxTokens, contextWindowTokens, temperature, and related fields.

Provider selection follows this practical rule:

Explicit provider in the active preset or implicit default config wins.
provider: "auto" tries model-name keywords, configured keys, local base URLs, and gateway providers.
Gateway providers such as OpenRouter and AiHubMix can route many model families, so the model name must be valid for that gateway.
Local providers should normally be explicit because generic local model names such as llama3.2 do not always contain provider keywords.

Model Name Prefixes

family/model-name does not always select provider family. Prefix-based provider inference only runs when the active provider is "auto".

Explicit provider wins: provider: "openrouter" with model: "anthropic/claude-sonnet-4.5" calls OpenRouter, not Anthropic.
With provider: "auto", a prefix matching a configured built-in or named custom provider can select that provider. Named custom prefixes are stripped before request, so companyProxy/gpt-4o-mini is sent upstream as gpt-4o-mini.
With an explicit named custom provider, the model is sent as written; provider: "companyProxy" with model: "openai/gpt-4o-mini" sends openai/gpt-4o-mini to companyProxy.

Pin provider in presets when using gateway catalog IDs such as anthropic/claude-sonnet-4.5.

Model Presets

Model presets are the recommended model configuration surface. Use them when you want named model choices, runtime /model switching, or reusable fallback targets.

{
  "modelPresets": {
    "fast": {
      "label": "Fast",
      "provider": "openrouter",
      "model": "anthropic/claude-sonnet-4.5",
      "maxTokens": 4096,
      "contextWindowTokens": 65536,
      "temperature": 0.1
    },
    "deep": {
      "label": "Deep",
      "provider": "anthropic",
      "model": "claude-opus-4-5",
      "maxTokens": 8192,
      "contextWindowTokens": 200000,
      "temperature": 0.1
    }
  },
  "agents": {
    "defaults": {
      "modelPreset": "fast"
    }
  }
}

The preset name default is reserved for the implicit agents.defaults settings. Do not define modelPresets.default; use /model default to return to the direct agents.defaults.* fields in older configs.

Fallback Models

Fallbacks are useful for transient provider failures, rate limits, or model availability issues. Keep fallbacks compatible with the task size and tool use. Prefer fallback presets so each candidate has a name and a complete provider, model, generation, and context-window configuration.

{
  "modelPresets": {
    "fast": {
      "label": "Fast",
      "provider": "openrouter",
      "model": "anthropic/claude-sonnet-4.5",
      "maxTokens": 4096,
      "contextWindowTokens": 65536,
      "temperature": 0.1
    },
    "deep": {
      "label": "Deep",
      "provider": "anthropic",
      "model": "claude-opus-4-5",
      "maxTokens": 8192,
      "contextWindowTokens": 200000,
      "temperature": 0.1
    },
    "localSmall": {
      "label": "Local Small",
      "provider": "ollama",
      "model": "llama3.2",
      "maxTokens": 4096,
      "contextWindowTokens": 32768,
      "temperature": 0.2
    }
  },
  "agents": {
    "defaults": {
      "modelPreset": "fast",
      "fallbackModels": ["deep", "localSmall"]
    }
  }
}

String entries in fallbackModels are preset names, not raw model names. nanobot tries them in order after the active preset. Each fallback preset uses its own provider, model, maxTokens, contextWindowTokens, temperature, and optional reasoningEffort.

Use inline fallback objects only when a model is not worth naming as a preset:

{
  "modelPresets": {
    "fast": {
      "provider": "openrouter",
      "model": "anthropic/claude-sonnet-4.5",
      "maxTokens": 4096,
      "contextWindowTokens": 65536
    }
  },
  "agents": {
    "defaults": {
      "modelPreset": "fast",
      "fallbackModels": [
        {
          "provider": "deepseek",
          "model": "deepseek-v4-pro",
          "maxTokens": 4096,
          "contextWindowTokens": 262144
        }
      ]
    }
  }
}

fallbackModels belongs under agents.defaults, not inside each preset. If fallback candidates use smaller context windows, nanobot builds context using the smallest window in the active chain so every candidate can receive the same prompt. See configuration.md#model-fallbacks for failure conditions.

Quick Checks

Run these before debugging a chat app:

nanobot status
nanobot agent -m "Hello!"

If nanobot agent -m "Hello!" fails:

Symptom	Likely cause
401, unauthorized, invalid API key	Key is missing, expired, copied with whitespace, or stored under the wrong provider
model not found	Model ID does not exist for the selected provider or gateway
connection refused	Local provider server is not running or `apiBase` points to the wrong port
provider not found	The active preset uses a misspelled provider; use registry names such as `openrouter`, `anthropic`, `ollama`, `vllm`, `lm_studio`
works in CLI but not chat app	Provider is fine; debug gateway/channel setup in `chat-apps.md` or `troubleshooting.md`

For the complete provider table and advanced provider-specific notes, see configuration.md#providers.

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Providers and Models

Choose a Provider Without Guessing

Minimal Shape

Provider, Model, API Key, and Base URL

Common Provider Patterns

OpenRouter Gateway

Anthropic Direct

OpenAI Direct

Custom OpenAI-Compatible Endpoint

Ollama

vLLM or Other Local OpenAI-Compatible Server

LM Studio

AWS Bedrock

OAuth Providers

Provider Resolution

Model Name Prefixes

Model Presets

Fallback Models

Quick Checks

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providers.md

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providers.md

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Providers and Models

Choose a Provider Without Guessing

Minimal Shape

Provider, Model, API Key, and Base URL

Common Provider Patterns

OpenRouter Gateway

Anthropic Direct

OpenAI Direct

Custom OpenAI-Compatible Endpoint

Ollama

vLLM or Other Local OpenAI-Compatible Server

LM Studio

AWS Bedrock

OAuth Providers

Provider Resolution

Model Name Prefixes

Model Presets

Fallback Models

Quick Checks