> ## Documentation Index
> Fetch the complete documentation index at: https://docs.cogos.natureselect.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Configuration

> Configure LLM providers, persistence, templates, and runtime behavior.

CogOS resolves configuration from multiple sources (highest priority wins):

1. **Environment variables** (`API_KEY`, `MODEL`, `BASE_URL`)
2. **YAML config file** (`configs/cogos.yaml`, created by `cogos init`)
3. **Dataclass defaults**

## Config File

Generated by `cogos init`:

```yaml theme={null}
llm:
  api_key: ""                            # or use API_KEY env var
  model: "gpt-5.4"                       # any OpenAI-compatible model
  base_url: "https://api.openai.com/v1"  # endpoint URL
  request_delay: 0.5

agent:
  max_iterations: 5
  temperature: 0.0
  max_tokens: 3000
  disable_thinking: true
  schema_update_rounds: 0               # auto-update every N chat rounds (0 = disabled)

chatbot:
  max_tokens: 4096
  context_rounds: 10                    # recent chat rounds as context (0 = single-turn)

persistence:
  session_dir: "./sessions"
  schemas_dir: "./schemas"              # standalone schema files for cross-session sharing

schema:
  inspect_max_depth: 3                  # depth for schema overview in prompts
  inspect_show_values: false            # include values in overview (costs tokens)

templates:
  templates_dir: "./templates"           # user-defined template JSON files
  custom_templates_dir: "./templates/custom"  # user custom templates (git-ignored)
  schema_template: ""                    # auto-load on startup (e.g. "general")

listen:
  listen_mode: false                     # enable via CLI --listen or set to true
  build_every_n_turns: 5                 # run build CM every N conversation turns

helpers:
  enable_forget_handling: false          # strip forgotten phrases from recalled data
  enable_sensitive_handling: false        # add PII warning section to chatbot prompt

server:
  host: "0.0.0.0"
  port: 8000
```

## Config File Resolution

| Priority | Path                                      | Description                           |
| -------- | ----------------------------------------- | ------------------------------------- |
| 1        | Explicit path (`-c` / `from_file("...")`) | User-specified                        |
| 2        | `configs/cogos.yaml`                      | User config (created by `cogos init`) |
| 3        | `configs/cogos.default.yaml`              | Default template (tracked by git)     |

## Key Settings

| Config Key                          | Description                                                                                                                             | Default     |
| ----------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------- | ----------- |
| `chatbot.context_rounds`            | Number of recent chat rounds included as conversation context. When exceeded, schema memory is auto-injected. Set to 0 for single-turn. | `10`        |
| `agent.schema_update_rounds`        | Auto-update schema from chat context every N rounds. Set to 0 to disable.                                                               | `0`         |
| `persistence.schemas_dir`           | Directory for standalone schema files shared across sessions. Backups are stored in `backups/` subdirectory.                            | `./schemas` |
| `listen.build_every_n_turns`        | In listen mode, run the build CM every N conversation turns.                                                                            | `5`         |
| `schema.inspect_max_depth`          | Depth for schema overview in CM prompts.                                                                                                | `3`         |
| `helpers.enable_forget_handling`    | Strip forgotten phrases from recalled data in `chat()`.                                                                                 | `false`     |
| `helpers.enable_sensitive_handling` | Add PII warning section to the chatbot prompt.                                                                                          | `false`     |

## Supported LLM Providers

Any OpenAI-compatible API works:

| Provider   | `base_url`                     | `model` example                        |
| ---------- | ------------------------------ | -------------------------------------- |
| OpenAI     | `https://api.openai.com/v1`    | `gpt-5.4`                              |
| OpenRouter | `https://openrouter.ai/api/v1` | `google/gemini-3.1-flash-lite-preview` |
| vLLM       | `http://localhost:8000/v1`     | `meta-llama/Llama-3-8b`                |

## Loading Config in Python

```python theme={null}
from cogos import CogOSConfig

config = CogOSConfig.from_file()                      # auto-resolve + env vars
config = CogOSConfig.from_file("configs/cogos.yaml")   # explicit path
config = CogOSConfig.from_env()                        # env vars only
config = CogOSConfig(model="gpt-5.4")                  # direct construction
```