> ## Documentation Index
> Fetch the complete documentation index at: https://chatcli.edilsonfreitas.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Devin Provider — the local Devin CLI as an LLM transport

> The DEVIN provider wraps Cognition's local Devin CLI as a pure LLM transport: ChatCLI keeps 100% of the context, memory, tools and harness; Devin is only the pipe to the model. No undocumented Cognition APIs involved.

ChatCLI's **DEVIN** provider drives the local `devin` binary in non-interactive mode and uses it purely as a **transport to reach the LLM behind it**. Everything else — conversation, context attachment, memory, compaction, sessions, the agent/coder tool protocol — stays in ChatCLI.

<Info>
  **Why a wrapper?** In enterprise deployments Devin is customized by Cognition (API + IDE integrations) and the HTTP API is not documented. The CLI is the **supported surface** and carries its own SSO authentication (`devin auth login`) — ChatCLI never speaks the private protocol, so Cognition-side changes are absorbed by their CLI, not by you.
</Info>

## Setup

1. Install the Devin CLI and authenticate once (corporate SSO):

```bash theme={"system"}
devin auth login
```

2. That's it — ChatCLI registers the provider automatically when the binary resolves (from `PATH`, or `DEVIN_CLI_PATH`):

```bash theme={"system"}
chatcli --provider DEVIN --model gpt-5.6-terra -p "hello"
# or interactively: /switch --provider DEVIN
```

No API key, no OAuth setup in ChatCLI: authentication belongs to the `devin` binary. Without the binary the provider simply doesn't appear — same UX as a provider without credentials.

## Models

The catalog mirrors what the enterprise CLI serves (29 models): the `claude-*` line (sonnet-5, opus 4.5–4.8, haiku), `gpt-5.x` including the **5.6 tiers** (sol/terra/luna), `gemini-3.x`, `glm-5.2`, `kimi-k2.x`, `deepseek-v4-pro`, and Cognition's own `swe-1.5`…`swe-1.7-lightning`. Any model string passes through — the catalog is bookkeeping, not a gate.

```bash theme={"system"}
/switch --model swe-1.7-lightning
/switch --model claude-sonnet-4.6      # note: Devin slugs use dots
```

## How the transport works

* **Stateless per turn** — the full flattened history goes on every call (never `--resume`), so conversation state never splits between ChatCLI and Devin's servers. Compaction, `/session load` and context edits keep working unchanged.
* **The inner agent can't act** — each call runs in a fresh empty directory with a transport preamble that forbids Devin's *native* tools while explicitly deferring to ChatCLI's own textual tool protocol. In agent/coder modes the model sees ChatCLI's full tool catalog and emits `<tool_call .../>` markup normally — ChatCLI executes, not Devin.
* **Clean replies** — the answer is extracted between sentinel markers so Devin's harness chrome is discarded; prompt files are always coerced to valid UTF-8 (the CLI rejects invalid bytes); invocations are serialized per process so background work (memory extraction) never races a live turn.

## Environment variables

| Variable                    | Purpose                                                | Default             |
| --------------------------- | ------------------------------------------------------ | ------------------- |
| `DEVIN_MODEL`               | Default model                                          | `claude-sonnet-4.6` |
| `DEVIN_CLI_PATH`            | Explicit binary path                                   | `devin` from `PATH` |
| `DEVIN_CLI_PERMISSION_MODE` | `--permission-mode` passed to the CLI                  | `auto`              |
| `DEVIN_CLI_AGENT_CONFIG`    | Declarative agent-config file (hardened tool lockdown) | —                   |
| `DEVIN_CLI_TIMEOUT`         | Per-turn ceiling                                       | `10m`               |
| `DEVIN_CLI_SANDBOX`         | Pass `--sandbox` (research preview)                    | `false`             |
| `DEVIN_CLI_EXTRA_ARGS`      | Extra CLI args escape hatch                            | —                   |

All exposed in `/config providers`.

## Limitations (honest ones)

* **No token/cost reporting** — the CLI doesn't expose usage, so the cost tracker records zero (cost lives in the Cognition subscription; the pricing layer never bills a routed `claude-*`/`gpt-*` model as if it were the direct API).
* **Spawn latency** — each turn pays a subprocess start plus Devin's harness overhead. If that matters for heavy coder use, an ACP-based persistent transport (`devin acp`) is the natural evolution.
* **Vision doesn't pass through** — the transport is flat text; image attachments never reach the backing model.

## See also

* [Supported Models](/reference/supported-models) — the DEVIN tab
* [Environment Variables](/reference/environment-variables)
* [MCP Server](/features/mcp-server) — combine both: expose ChatCLI over MCP and route `agent_task` to `provider: "DEVIN"`