# CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

## What this is

`familiar` is an [MCP](https://modelcontextprotocol.io) server giving a local AI a window into an EVE Online account and the New Eden universe — public market/universe lookups plus authenticated character **and corp** data, with opt-in write actions. Python + [FastMCP](https://github.com/jlowin/fastmcp), managed with `uv`.

Note: the project began "read-only by design" but is now **read + write** (writes gated behind safety, see below). The README's older read-only framing is superseded.

## Commands

```bash
uv sync                       # install deps (incl. dev group)
uv run pytest                 # full suite; FAILS under 80% coverage (configured in pyproject addopts)
uv run pytest tests/test_market.py::test_get_market_price   # single test
uv run ruff format .          # format
uv run ruff check .           # lint (run both before committing; CI enforces them)
uv run familiar               # run the MCP server over stdio (how Claude launches it)
uv run familiar serve         # run the streamable-HTTP transport (remote MCP; needs FAMILIAR_HTTP_TOKEN)
uv run familiar login         # browser EVE SSO login (adds a character; run once per character)
uv run familiar login --no-browser  # headless login: paste the callback URL on stdin
uv run familiar status        # list logged-in characters
uv run familiar writes disable # block write actions (default: enabled on stdio, disabled on HTTP)
```

There is no separate build step; `uv build` produces the wheel (CI does this on merge).

## Architecture

**Server assembly.** [src/familiar/server.py](src/familiar/server.py) creates the single `FastMCP` instance and calls `register(mcp)` on each tool module. Every tool module (market, universe, account, industry, trade, structures, killmails, profile, corp, corp_economy, misc, comms, contacts, fittings, fleet, ui, planets, writes) follows the same shape: **module-level async functions** + a `TOOLS` list + `register(mcp)` that loops `mcp.tool(fn)`. Tools are plain importable functions (so tests call them directly); registration is separate. To add tools: new module → import + register in server.py.

**Transport (stdio default, opt-in HTTP).** `familiar` (no args) runs `mcp.run()` over **stdio** (how Claude launches it) — local, no auth. `familiar serve` runs `server.serve_http()`: the FastMCP **streamable-HTTP** transport bound to loopback (`FAMILIAR_HTTP_HOST`/`FAMILIAR_HTTP_PORT`/`FAMILIAR_HTTP_PATH`, default `127.0.0.1:8080/mcp`) behind a TLS reverse proxy, for remote MCP clients (Mistral, Claude web/desktop/code, VS Code — see [doc/clients/](doc/clients/)). An unauthenticated `GET /healthz` liveness route (returns only status/server/version) is served for Docker/proxy probes. This transport-level auth is separate from the EVE-SSO/ESI auth in auth.py.

`configure_http(host=, token=, verifier=)` picks the auth provider from `FAMILIAR_AUTH_MODE`:

- **`bearer`** (default): a `StaticTokenVerifier` from `FAMILIAR_HTTP_TOKEN` (bad/missing bearer → 401 + `WWW-Authenticate: Bearer`). **Fail-closed** — no token → `SystemExit`, unless `FAMILIAR_ALLOW_INSECURE_BIND=true` explicitly permits a tokenless bind (the message distinguishes loopback vs a public interface via `config.is_loopback`).
- **`oauth`**: familiar is an OAuth 2.1 **resource server** only — a `JWTVerifier` (JWKS from `FAMILIAR_OAUTH_JWKS_URI` or discovered from `FAMILIAR_OAUTH_ISSUER`'s OIDC metadata, validating `issuer` + `audience`) wrapped in a `RemoteAuthProvider` that serves `/.well-known/oauth-protected-resource/<path>`. Config: `FAMILIAR_OAUTH_ISSUER`, `FAMILIAR_OAUTH_RESOURCE` (this server's public URL, required), `FAMILIAR_OAUTH_AUDIENCE` (defaults to resource). No DCR/authorization-server in familiar; needs an external IdP (Authentik/Keycloak) for the claude.ai web connector.

Either mode calls `writes.set_http_context(True)`, flipping the **write default to disabled** unless `FAMILIAR_ENABLE_WRITES` is explicitly truthy (only the default resolution changes; `writes.guard` is untouched).

**ESI access.** [esi.py](src/familiar/esi.py) is a thin async httpx wrapper (`client()` singleton, `get/post/put/delete`, `get_all_pages` for `X-Pages` pagination, Bearer `token=` for authed calls, uniform `EsiError`). Base URL and datasource are env-overridable. [zkill.py](src/familiar/zkill.py) mirrors it for zKillboard. Both expose `set_client()` so tests inject an `httpx.MockTransport`.

**Auth is multi-character.** [auth.py](src/familiar/auth.py) does EVE SSO PKCE (no client secret), stores a **dict of characters keyed by id** in one Fernet-encrypted file (`load_store`/`_save_character`/`list_characters`/`remove_character`), and `get_auth(character_id)` returns a valid access token, refreshing via the rotating refresh token when near expiry. The legacy single-character file is migrated on load. Config (client id, callback `localhost:8765`, the 73 read+write scopes split into `READ_SCOPES`/`WRITE_SCOPES`) lives in [config.py](src/familiar/config.py), all env-overridable.

**Per-character / per-corp pattern.** [charutil.py](src/familiar/charutil.py) is the backbone of every authenticated tool. `run_per_character(character, fetch)` runs a fetcher for one named character or **all** logged-in ones (when `character` is None), returning a uniform `{"characters": [...]}`. `run_per_corp` additionally resolves each character's `corporation_id` (corp endpoints need the right corp role or ESI 403s). `one_token` picks a single token for thing-scoped lookups (e.g. a structure). `summarize(items, limit)` gives `{count, sample}`. account.py and all read modules build on these.

**Write safety — the choke point.** [writes.py](src/familiar/writes.py) `guard(action, params, confirm, execute)` is the single gate every mutating tool calls. `confirm=False` → dry-run preview (nothing happens); `confirm=True` but writes disabled → `WriteDisabled`; `confirm=True` + enabled → execute + append to an audit log. Writes are **on by default over stdio** (opt out via `familiar writes disable`; toggle via `familiar writes enable`/`disable` or `FAMILIAR_ENABLE_WRITES`) but **off by default over HTTP** (see the transport note — `set_http_context` flips the default; `FAMILIAR_ENABLE_WRITES` still overrides). Write tools take a *required* `character` and a `confirm` flag; reads take an *optional* `character`. When adding a write tool, route it through `writes.guard` — never call a mutating ESI endpoint directly.

## Testing conventions

Tests use [tests/conftest.py](tests/conftest.py): the `mock_esi` fixture installs a mock ESI client driven by a request handler, and `route(req, {substring: body})` dispatches by path substring. Async tools are driven with `asyncio.run(...)` (no async-test plugin). Authenticated-tool tests monkeypatch `auth.list_characters` / `auth.get_auth` / `auth.resolve_character` rather than touching the real token store; write tests set `FAMILIAR_DATA_DIR` to a tmp dir and `FAMILIAR_ENABLE_WRITES`. `make_jwt(claims)` builds fake access tokens.

## Git / CI workflow

- Work happens on `dev`. Feature branches → PR → fast-forward merge into `dev` → delete branch. Cut a release by bumping the version in `pyproject.toml` / `src/familiar/__init__.py` and opening a `dev → main` fast-forward PR (publishes the clean version).
- `main` and `dev` are protected: no direct pushes, **signed commits required** (the user's git auto-signs), merge via PR.
- Two workflows run lint + test on every PR/push. `.gitea/workflows/ci.yml` additionally builds + publishes the Python wheel to the Gitea PyPI registry on a merge to main/dev (auth via the `REGISTRY_TOKEN` secret; twine must NOT use `--skip-existing`; dev publishes a unique `.devN` pre-release). `.gitea/workflows/docker.yml` additionally builds + smoke-tests the Docker image (`docker/Dockerfile`, runs `familiar serve`; checks non-root, `/healthz` 200, MCP 401 without / 200 with a token) on every run and, on a merge to main/dev, pushes it to the Gitea container registry `git.hiddenden.cafe/hiddenden/familiar` (main → `:latest`/`:main`, dev → `:dev`, plus `:sha-<12>`) using the same `REGISTRY_TOKEN`. The two workflows are independent and must not interfere.
- **Do NOT attribute commits, merges, or PRs to Claude / Claude Code.** No `Co-Authored-By: Claude ...` trailer on commits and no "Generated with Claude Code" footer in PR descriptions. Keep messages plain and authored by the user.