# DeerFlow

DeerFlow is an agent harness: a LangGraph-based backend with thread-isolated
sandboxes, memory, subagents, skills and MCP tools, and a Next.js frontend. IM
channels connect through the Gateway. `CLAUDE.md` imports this file; edit
guidance here, not in the shim.

## How guidance is organized

Rules live in the `AGENTS.md` nearest to the code. Before you edit a directory,
read every `AGENTS.md` from that directory up to this file. Some coding agents do
not load the nested files on their own.

| Area | Guide |
| --- | --- |
| Backend: harness, Gateway, channels, tests | [backend/AGENTS.md](backend/AGENTS.md) |
| Frontend | [frontend/AGENTS.md](frontend/AGENTS.md) |
| nginx, Compose, provisioner | [docker/AGENTS.md](docker/AGENTS.md) |
| Orchestration scripts, `scripts/pnpm.py` | [scripts/AGENTS.md](scripts/AGENTS.md) |
| Skill review, skill tests | [skills/AGENTS.md](skills/AGENTS.md) |
| Extension examples | `examples/*/AGENTS.md` |

Humans start at [README.md](README.md), [CONTRIBUTING.md](CONTRIBUTING.md) and
[docs/guide/](docs/guide/).

## Service topology

| Service | Port | Role |
| --- | --- | --- |
| Nginx | 2026 | The single entry point; open this in the browser |
| Gateway | 8001 | FastAPI REST API and the embedded agent runtime |
| Frontend | 3000 | Next.js web interface |
| Provisioner | 8002 | Optional; only for provisioner or Kubernetes sandboxes |

Nginx serves the frontend, proxies `/api/*` to the Gateway and rewrites
`/api/langgraph/*` to the Gateway's native routes.

## Repository map

| Path | Content |
| --- | --- |
| `backend/packages/harness/` | `deerflow-harness`, import `deerflow.*`: the agent framework |
| `backend/packages/extension-api/` | `deerflow-extension-api`: the public extension contract |
| `backend/app/` | The Gateway and the IM channels, import `app.*` |
| `frontend/` | The Next.js app (pnpm) |
| `docker/`, `deploy/helm/` | Compose files, nginx config, provisioner, Helm chart |
| `skills/public/`, `skills/custom/` | Committed skills and local, gitignored skills |
| `contracts/` | JSON contracts shared across components |
| `examples/` | Installable extension examples |
| `scripts/`, `tests/` | Root orchestration scripts, and tests for public skills |

`config.yaml` and `extensions_config.json` are copied from the example files at
the repository root. Both are gitignored and the Gateway can write them. Do not
commit them.

## Commands

`make help` lists the root targets. First setup is `make config`, then
`make install`, then `make dev`, which serves the stack on `localhost:2026` and
writes `logs/gateway.log` and `logs/frontend.log`.

```bash
cd backend && make test && make test-blocking-io   # offline suites
cd backend && make format                          # CI runs ruff format --check
cd backend && python -m pytest tests/path/test_x.py::test_name -q
cd frontend && pnpm check && pnpm test
cd frontend && pnpm rstest run <pattern>
make check-agent-guidance                          # size budget of these guides
```

## Rules for every change

- **Evaluate an extension first.** Before you add a feature to core code, check
  whether it can ship as a packaged extension. Core is the place for bug fixes
  and for changes to the agent loop, memory, context compaction and
  authentication. When the existing hooks cannot express a feature, add a
  generic hook to the extension contract and an extension that uses it; business
  logic is not hard-coded into core. Contract and examples:
  [extensions guide](backend/packages/harness/deerflow/extensions/AGENTS.md),
  `examples/`.
- **Extensions are operator-controlled code.** They load from `plugins:` in
  `config.yaml`. The list stays out of the API-writable `extensions_config.json`,
  because loading an extension imports code with Gateway privileges. Install
  from trusted sources only, and restart the Gateway after every extension
  change.
- **Ship tests with every feature and bug fix.**
- **Document behavior next to its topic, in the same change**: user-facing
  behavior in `docs/guide/` or `backend/docs/`. `README.md` is an index; change
  it only to add or re-point a link.
- **Keep the version fields identical**: `backend/pyproject.toml`,
  `backend/packages/harness/pyproject.toml`, `frontend/package.json`, and
  `version` and `appVersion` in `deploy/helm/deer-flow/Chart.yaml`.
  `scripts/bump_version.sh <ver>` updates them and `backend/uv.lock`, and
  `scripts/verify_versions.sh <ver>` checks the result. Tag CI blocks publishing
  on drift. See [RELEASING.md](RELEASING.md).

## What belongs in an `AGENTS.md`

An agent reads these files on every task, so each line costs attention. A guide
holds four kinds of content:

1. Scope: what the directory owns, in one or two sentences.
2. Verification: the exact commands.
3. Traps: where the code misleads, or where a plausible change breaks something
   that a local test run does not show.
4. Decisions and their reasons that the code cannot state, and links to docs.

Values, defaults, field lists, function inventories, test names, issue numbers
and history stay in the code, the tests and git. Write full sentences in the
positive form and give the reason. `make check-agent-guidance` enforces the size
budget.