feat(#2 ): consume GET /me + GET /capabilities via --whoami one-shot

v1 coverage-audit slice (capabilities+me). Both endpoints had no caller; add them as cheap boot-time debug primitives. - sessions.py: get_me (GET /me — identity/whoami) + get_capabilities (GET /capabilities — Echo ephemeral-template discovery). Mirror get_persona_state: 200 -> parsed dict verbatim, non-200 -> SessionApiFailed. Freeform dicts (frozen OpenAPI types both as objects). - cli.py: new --whoami one-shot mode (mirrors --send). Fetches both, prints an identity + capabilities report, exits. Standalone probe: mutually exclusive with --send/--session/--new/--agent; opens no session. New ParsedArgs.whoami field + main() dispatch. - Contract #2 amended (2 FNs) + validated. TDD: 5 wrapper tests + 5 cli tests (validation + mode + error). Coverage map: REST 9/40. Suite 538 green; touched code ruff-clean. Audit note: /capabilities is the Echo ephemeral-template discovery endpoint, not a generic server-caps endpoint (coverage-map framing corrected). TUI-surfacing of /me + /capabilities deferred.
2026-06-30 22:21:59 -07:00
9 changed files with 334 additions and 23 deletions
@@ -206,3 +206,48 @@ TESTS:
  limit_above_max [adversarial]: limit=300 → AssertionError; no HTTP issued
  empty_cursor [adversarial]: cursor="" → AssertionError; no HTTP issued
 ```
+
+## Amendment 2026-06-30 — boot-time introspection reads (v1 coverage-audit: capabilities+me)
+
+The v1 coverage-audit added two read-only server-introspection endpoints as
+cheap debug primitives (surfaced via a new `ratatoskr --whoami` one-shot). Both
+mirror `get_persona_state`: GET, 200 → parsed dict verbatim, any non-200 →
+`SessionApiFailed`. The frozen OpenAPI types both responses as freeform objects,
+so the wrappers return `dict[str, Any]` (not a typed dataclass).
+
+```contract
+FN get_me(client: httpx.AsyncClient) -> dict[str, Any]
+BRIEF: GET /me — the authenticated principal's identity + key metadata (spec §GET /me). Boot-time whoami: verify the key without agent-config side effects. Returns parsed JSON verbatim; spec documents {user_id, scopes, tier, display_name?, key_id?, key_label?, ...} with optional fields OMITTED (not null). Read-only, rate-exempt, no audit emission.
+PRE: [PRE-001 hard] client is not None -- assert client is not None
+POST: [POST-001 return_value] on 200 returns resp.json() unmodified -- assert result == resp.json()
+ERROR_ROUTING:
+  HTTP non-200 (incl. 401 bad/absent key when auth enabled):
+    local_handling: raise SessionApiFailed(status=resp.status_code, body=resp.content)
+    flow_control: abort
+    state_recovery: none (caller decides: bad key → re-key; degraded tier="unknown" is still a 200)
+STEPS:
+  1. [setup, prescriptive] assert client is not None
+  2. [sequential, prescriptive] resp = await client.get("/me")
+  3. [branch, prescriptive] IF resp.status_code == 200: RETURN resp.json(); ELSE RAISE SessionApiFailed
+TESTS:
+  happy_authenticated [happy,tracer]: 200 {user_id, scopes, tier, key_id} → dict returned verbatim
+  anonymous_dev_mode: 200 {user_id:"anonymous", tier:"anonymous"} → dict; no key_* fields (omitted)
+  401_raises [error]: 401 → SessionApiFailed(status=401)
+
+FN get_capabilities(client: httpx.AsyncClient) -> dict[str, Any]
+BRIEF: GET /capabilities — server capability discovery (spec §Ephemeral Templates). Returns {ephemeral_templates: {echo: {allowed_models, default_model, system_prompt_max_bytes}}}. Any authenticated caller may read it (no instantiate scope). Parsed dict verbatim; any non-200 → SessionApiFailed.
+PRE: [PRE-001 hard] client is not None -- assert client is not None
+POST: [POST-001 return_value] on 200 returns resp.json() unmodified -- assert result == resp.json()
+ERROR_ROUTING:
+  HTTP non-200:
+    local_handling: raise SessionApiFailed(status=resp.status_code, body=resp.content)
+    flow_control: abort
+    state_recovery: none
+STEPS:
+  1. [setup, prescriptive] assert client is not None
+  2. [sequential, prescriptive] resp = await client.get("/capabilities")
+  3. [branch, prescriptive] IF resp.status_code == 200: RETURN resp.json(); ELSE RAISE SessionApiFailed
+TESTS:
+  happy [happy]: 200 {ephemeral_templates:{echo:{...}}} → dict returned verbatim
+  non_200_raises [error]: 500 → SessionApiFailed(status=500)
+```
@@ -48,7 +48,7 @@ resolved (§ Surface 1, scope-resolution table).

 | Surface | Points | ✅ covered-live | ⬜ gap (in-scope) | 🚫 excluded-by-design |
 |---|---|---|---|---|
-| REST (OpenAPI 2.2.0, path groups) | 40 | 7 | 11 | 22 |
+| REST (OpenAPI 2.2.0, path groups) | 40 | 9 | 9 | 22 |
 | SSE events | 11 | 11 | 0 | 0 |
 | Bifrost provider planes | 8 verbs | 8 | 0 | (10 gated verbs deferred) |

@@ -75,6 +75,8 @@ sub-gap).
 | `POST /agents/define` | ✅ | `tier3.py:175` → `_run_define` | Tier-3 create |
 | `PATCH /agents/{id}` | ✅ | `tier3.py:219` → `_run_patch` | Tier-3 mutate (system_prompt/model) |
 | `DELETE /agents/{id}` | ✅ | `tier3.py:242` → `_run_delete` | Tier-3 hard-delete |
+| `GET /me` | ✅ | `sessions.py:411` `get_me` → `cli.py` `--whoami` | identity/whoami probe; 401→SessionApiFailed |
+| `GET /capabilities` | ✅ | `sessions.py:428` `get_capabilities` → `cli.py` `--whoami` | Echo ephemeral-template discovery |

 **Sub-gaps inside ✅ path groups** (the method we use is live; a sibling method
 on the same path is an unwired frontier item — see frontier Tier 1):
@@ -95,8 +97,6 @@ on the same path is an unwired frontier item — see frontier Tier 1):
 | `GET /admin/events` | ⬜ | design-brief §5 v1 **AdminEvents pane**; = issue **#11**, **blocked** on `admin.events.read` scope (infra-ops) |
 | `GET /admin/sessions/{id}/bifrost` | ⬜ | design-brief §5 v1 **BifrostState widget** — never built; admin-key-gated |
 | `GET /admin/sessions/{id}/tools` | ⬜ | design-brief §5 v1 **Tools widget** — never built; admin-key-gated |
-| `GET /capabilities` | ⬜ | server capability discovery — a turn flows through what's advertised |
-| `GET /me` | ⬜ | whoami / key-identity — "which key am I against" is a debug primitive |
 | (`GET /sessions` picker · resume) | ⬜ | sub-gaps above — presenter-wiring only, wrappers exist |

 **Tier 2 — rounds out I/O coverage under A (postdates the design-brief):**
@@ -153,6 +153,8 @@ decision. Captures rationale that won't be obvious from code alone.

 - `[2026-06-30]` **(b2) session-picker SHIPPED (`v0.18.7`) — bare TUI mode → startup picker (design-brief §4).** `list_sessions` had NO caller; now bare TUI mode (no `--session`/`--new`) resolves via `list_sessions` in `_resolve_then_run`: **0 sessions → `[no_sessions]` error, exit 14** (resume-only, honors §4 "no in-app session creation — `--new` flag only"); **exactly 1 → auto-resume** (§4 "picker only when >1"); **≥2 → new `SessionPickerApp`** (Textual `App[str|None]`, mirrors `AgentPickerApp`; ListView of sessions) → resume the pick (Esc/Ctrl-D → exit 0). cli `_parse` relaxed: bare TUI now VALID (was "pass exactly one" error); `--send` still requires one flag (non-interactive, no picker); `--agent` forbidden in bare mode; `run_tui` PRE-002 XOR→"not both". Direct in-session TDD (contract #6 amendment, validated OK): 3 widget pilot tests + 5 `_resolve_then_run` resolution tests + 3 cli validation tests. Suite **528 green**; touched code ruff-clean (mypy: only the `BINDINGS` list-invariance warning every App in tui.py already carries — consistent). **DESIGN NOTE — bare+0-sessions → error (clause-consistent). The friendlier auto-fall-through-to-new alternative is DEFERRED pending operator preference (it would create a session without `--new`, against the §4 negative clause).** **Frontier now: `GET /capabilities`+`GET /me` → BifrostState/Tools widgets (`GET /admin/sessions/{id}/{bifrost,tools}`, admin-key) → #11 AdminEvents (BLOCKED on `admin.events.read`).** heid-code-review NOT run on b1 or b2 (offered).

+- `[2026-06-30]` **capabilities+me slice SHIPPED (`v0.18.8`) — `GET /me` + `GET /capabilities` consumed via a new `--whoami` one-shot.** `get_me`/`get_capabilities` added to sessions.py (mirror `get_persona_state`: 200→dict verbatim, non-200→`SessionApiFailed`; freeform dicts per the frozen OpenAPI). New `ratatoskr --whoami` CLI mode (mirrors `--send`'s non-interactive shape) fetches both + prints an identity+capabilities report; standalone probe (mutually exclusive with `--send`/`--session`/`--new`/`--agent`, opens no session; new `ParsedArgs.whoami` field + main() dispatch). **`/capabilities` is the Echo EPHEMERAL-TEMPLATE discovery endpoint** (`{ephemeral_templates:{echo:{allowed_models,default_model,system_prompt_max_bytes}}}`), NOT a generic server-caps endpoint (audit finding — the coverage-map's earlier "server capability discovery" framing was imprecise). `/me` = whoami (`{user_id,scopes,tier,key_id?,...}`, optionals omitted-not-null). Contract-skip privilege invoked (low-effort GET wrappers) but contract #2 amended (2 FNs, validated OK) to keep the sessions spec canonical + honest test citations. TDD: 5 wrapper tests + 5 cli tests (validation + mode + error). Suite **538 green**; touched code ruff-clean (mypy: only `no-any-return` on `resp.json()`→dict, identical to the pre-existing `get_persona_state`). **Coverage: REST 9/40 ✅ (up from 7).** TUI-surfacing of /me (footer identity line) + /capabilities DEFERRED — the one-shot is the minimal tracer. **Frontier now: BifrostState + Tools widgets (`GET /admin/sessions/{id}/{bifrost,tools}`, admin-key-gated) → #11 AdminEvents (BLOCKED on `admin.events.read`).**
+
 _41 older entries (2026-05-* — the original debug-TUI/web build era) archived to archival-memory.md._

 _For per-issue TDD implementation notes, Volva findings, and contract amendments, see the git log — every per-issue commit carries a structured message capturing the trail._
@@ -4,7 +4,7 @@ build-backend = "hatchling.build"

 [project]
 name = "ratatoskr"
-version = "0.18.7"
+version = "0.18.8"
 description = "Worldtree Conversation API debug TUI — multi-pane observability dashboard"
 readme = "README.md"
 requires-python = ">=3.12"
@@ -12,7 +12,7 @@ import signal
 import sys
 from dataclasses import dataclass, field
 from importlib.metadata import PackageNotFoundError, version
-from typing import TextIO
+from typing import Any, TextIO

 import httpx

@@ -24,6 +24,8 @@ from ratatoskr.sessions import (
    SessionApiFailed,
    create_session,
    endpoint_for_plane,
+    get_capabilities,
+    get_me,
 )
 from ratatoskr.sse_client import (
    AffectUpdate,
@@ -97,6 +99,9 @@ class ParsedArgs:
    bifrost: BifrostBinding | None = None
    bifrost_plane: str | None = None
    consumer_key: str | None = None
+    # Standalone boot-time orientation probe: GET /me + GET /capabilities, print,
+    # exit. Mutually exclusive with the session/turn flags (opens no session).
+    whoami: bool = False


 class _ArgparseError(Exception):
@@ -121,6 +126,7 @@ def _parse_args(argv: list[str] | None) -> ParsedArgs:
    parser.add_argument("--api-key", dest="api_key")
    parser.add_argument("--server")
    parser.add_argument("--raw", action="store_true")
+    parser.add_argument("--whoami", action="store_true")
    # Issue #5: required for per-end-user agents (lofn etc.); optional otherwise (mimir).
    parser.add_argument("--end-user-id", dest="end_user_id", default=None)
    # Issue #17: bind the created session to our own Bifrost provider plane.
@@ -141,23 +147,32 @@ def _parse_args(argv: list[str] | None) -> ParsedArgs:
    # Issue #5 INV-001: --end-user-id, if passed, MUST be non-empty (mirrors --send).
    if ns.end_user_id is not None and not ns.end_user_id:
        raise UsageError("--end-user-id must be non-empty when passed")
-    if ns.session and ns.new:
-        raise UsageError("--session and --new are mutually exclusive")
-    if not ns.session and not ns.new:
-        # Bare TUI mode → startup session picker (design-brief §4). --send is
-        # non-interactive (no picker can open), so it still requires one flag;
-        # --agent belongs with --new (bare mode resumes, it doesn't create).
-        if ns.send is not None:
-            raise UsageError("--send requires --session or --new (no interactive picker)")
-        if ns.agent:
-            raise UsageError("--agent belongs with --new; bare TUI mode opens the session picker")
-    if ns.session and ns.agent:
-        raise UsageError("--agent is required with --new and forbidden with --session")
-    if ns.new and not ns.agent and ns.send is not None:
-        # Issue #8: --agent stays required for --send --new (non-interactive,
-        # cannot prompt). Bare --new (TUI mode) accepts None — picker drives
-        # the choice via list_agents in _resolve_then_run.
-        raise UsageError("--agent is required when --new is passed in --send mode")
+    if ns.whoami:
+        # Standalone boot-time probe (GET /me + /capabilities): opens no session.
+        if ns.send is not None or ns.session or ns.new or ns.agent:
+            raise UsageError(
+                "--whoami is a standalone probe (no --send/--session/--new/--agent)"
+            )
+    else:
+        if ns.session and ns.new:
+            raise UsageError("--session and --new are mutually exclusive")
+        if not ns.session and not ns.new:
+            # Bare TUI mode → startup session picker (design-brief §4). --send is
+            # non-interactive (no picker can open), so it still requires one flag;
+            # --agent belongs with --new (bare mode resumes, it doesn't create).
+            if ns.send is not None:
+                raise UsageError("--send requires --session or --new (no interactive picker)")
+            if ns.agent:
+                raise UsageError(
+                    "--agent belongs with --new; bare TUI mode opens the session picker"
+                )
+        if ns.session and ns.agent:
+            raise UsageError("--agent is required with --new and forbidden with --session")
+        if ns.new and not ns.agent and ns.send is not None:
+            # Issue #8: --agent stays required for --send --new (non-interactive,
+            # cannot prompt). Bare --new (TUI mode) accepts None — picker drives
+            # the choice via list_agents in _resolve_then_run.
+            raise UsageError("--agent is required when --new is passed in --send mode")

    api_key = ns.api_key or os.environ.get("WORLDTREE_API_KEY") or ""
    if not api_key:
@@ -206,6 +221,7 @@ def _parse_args(argv: list[str] | None) -> ParsedArgs:
        bifrost=bifrost,
        bifrost_plane=bifrost_plane,
        consumer_key=consumer_key,
+        whoami=ns.whoami,
    )


@@ -556,6 +572,56 @@ async def _amain(args: ParsedArgs) -> int:
            loop.remove_signal_handler(signal.SIGINT)


+def _format_whoami(me: dict[str, Any], caps: dict[str, Any]) -> str:
+    """Render the --whoami report: identity (GET /me) + server capabilities."""
+    lines = ["identity:"]
+    lines.append(f"  user_id: {me.get('user_id', '?')}")
+    lines.append(f"  tier: {me.get('tier', '?')}")
+    lines.append(f"  scopes: {', '.join(me.get('scopes', [])) or '(none)'}")
+    for k in ("display_name", "key_id", "key_label"):
+        if k in me:
+            lines.append(f"  {k}: {me[k]}")
+    lines.append("capabilities:")
+    templates = caps.get("ephemeral_templates", {})
+    if templates:
+        for name, spec in templates.items():
+            models = ", ".join(spec.get("allowed_models", []))
+            lines.append(
+                f"  ephemeral_template {name}: default={spec.get('default_model', '?')} "
+                f"max_bytes={spec.get('system_prompt_max_bytes', '?')} models=[{models}]"
+            )
+    else:
+        lines.append("  (no ephemeral templates advertised)")
+    return "\n".join(lines) + "\n"
+
+
+async def _whoami(args: ParsedArgs) -> int:
+    """--whoami one-shot: GET /me + GET /capabilities, print a compact report, exit.
+
+    A boot-time orientation probe (mirrors --send's non-interactive shape):
+    "who am I against this server, and what does it offer." Opens no session.
+    Errors land on stderr with the same [session_api_failed] / [network_error]
+    vocab + exit codes as the other modes.
+    """
+    assert isinstance(args, ParsedArgs)
+    async with httpx.AsyncClient(
+        base_url=args.server_url,
+        headers={"Authorization": f"Bearer {args.api_key}", "User-Agent": USER_AGENT},
+        timeout=httpx.Timeout(connect=10.0, read=10.0, write=10.0, pool=10.0),
+    ) as client:
+        try:
+            me = await get_me(client)
+            caps = await get_capabilities(client)
+        except SessionApiFailed as exc:
+            sys.stderr.write(f"[session_api_failed] status={exc.status} body={exc.body!r}\n")
+            return 20
+        except (httpx.ConnectError, httpx.ReadTimeout, httpx.TransportError) as exc:
+            sys.stderr.write(f"[network_error] {type(exc).__name__}: {exc}\n")
+            return 21
+        sys.stdout.write(_format_whoami(me, caps))
+    return 0
+
+
 def main(argv: list[str] | None = None) -> int:
    """Sync entry point. Maps UsageError/_AuthError to exit codes BEFORE the event loop."""
    assert argv is None or all(isinstance(a, str) for a in argv)
@@ -571,6 +637,8 @@ def main(argv: list[str] | None = None) -> int:
        # argparse's --help / --version short-circuit via SystemExit(0). Pass the code
        # through verbatim — argparse already printed help to stdout.
        return int(exc.code) if exc.code is not None else 0
+    if args.whoami:
+        return asyncio.run(_whoami(args))
    if args.send_content is None:
        # TUI mode — lazy import preserves INV-001 (no textual in cli at module scope).
        from ratatoskr.tui import run_tui
@@ -406,3 +406,35 @@ async def get_persona_state(
    if resp.status_code == 403 and error_code == "auth_scope_denied":
        raise AuthScopeDenied(scope="persona.read")
    raise SessionApiFailed(status=resp.status_code, body=resp.content)
+
+
+async def get_me(client: httpx.AsyncClient) -> dict[str, Any]:
+    """GET /me — the authenticated principal's identity + key metadata (spec §GET /me).
+
+    Boot-time whoami: verify the key without agent-config side effects. Returns
+    the parsed dict verbatim (freeform per the frozen OpenAPI; the spec documents
+    `{user_id, scopes, tier, display_name?, key_id?, key_label?, ...}`, optional
+    fields omitted-not-null). 401 (bad/absent key when auth is enabled) — like
+    every other non-200 — surfaces as SessionApiFailed (get_persona_state
+    precedent). Read-only, rate-exempt, no audit emission.
+    """
+    assert client is not None
+    resp = await client.get("/me")
+    if resp.status_code == 200:
+        return resp.json()
+    raise SessionApiFailed(status=resp.status_code, body=resp.content)
+
+
+async def get_capabilities(client: httpx.AsyncClient) -> dict[str, Any]:
+    """GET /capabilities — server capability discovery (spec §Ephemeral Templates).
+
+    Returns `{ephemeral_templates: {echo: {allowed_models, default_model,
+    system_prompt_max_bytes}}}` — what the server offers before a client decides
+    to instantiate. Any authenticated caller may read it (no scope). Parsed dict
+    verbatim; any non-200 → SessionApiFailed.
+    """
+    assert client is not None
+    resp = await client.get("/capabilities")
+    if resp.status_code == 200:
+        return resp.json()
+    raise SessionApiFailed(status=resp.status_code, body=resp.content)
@@ -1564,3 +1564,72 @@ class TestBifrostBindCli:
        )
        rc = await _amain(args)
        assert rc == 22
+
+
+class TestWhoami:
+    """--whoami one-shot probe (slice: capabilities+me): GET /me + GET /capabilities."""
+
+    def test_whoami_standalone_accepted(self) -> None:
+        """whoami_standalone_accepted: --whoami alone → valid; whoami=True, no turn flags."""
+        args = _parse_args(["--whoami", "--api-key", "k"])
+        assert args.whoami is True
+        assert args.send_content is None
+        assert args.session_id is None
+        assert args.new is False
+
+    def test_whoami_with_send_rejected(self) -> None:
+        """whoami_with_send_rejected [adversarial]: --whoami + --send → UsageError."""
+        with pytest.raises(UsageError, match="standalone probe"):
+            _parse_args(["--whoami", "--send", "hi", "--api-key", "k"])
+
+    def test_whoami_with_new_rejected(self) -> None:
+        """whoami_with_new_rejected [adversarial]: --whoami + --new → UsageError."""
+        with pytest.raises(UsageError, match="standalone probe"):
+            _parse_args(["--whoami", "--new", "--agent", "m", "--api-key", "k"])
+
+    @respx.mock
+    def test_whoami_mode_prints_report(self, capsys: pytest.CaptureFixture[str]) -> None:
+        """whoami_mode_prints_report [happy,tracer]: /me + /capabilities → stdout report; exit 0."""
+        respx.get("https://w.example/me").mock(
+            return_value=httpx.Response(
+                200,
+                json={
+                    "user_id": "alice",
+                    "scopes": ["conversations.read", "conversations.write"],
+                    "tier": "user",
+                    "key_id": "a1b2c3d4",
+                },
+            )
+        )
+        respx.get("https://w.example/capabilities").mock(
+            return_value=httpx.Response(
+                200,
+                json={
+                    "ephemeral_templates": {
+                        "echo": {
+                            "allowed_models": ["glm5-turbo"],
+                            "default_model": "glm5-turbo",
+                            "system_prompt_max_bytes": 32768,
+                        }
+                    }
+                },
+            )
+        )
+        rc = main(["--whoami", "--api-key", "k", "--server", "https://w.example"])
+        assert rc == 0
+        out = capsys.readouterr().out
+        assert "user_id: alice" in out
+        assert "tier: user" in out
+        assert "key_id: a1b2c3d4" in out
+        assert "ephemeral_template echo" in out
+        assert "glm5-turbo" in out
+
+    @respx.mock
+    def test_whoami_me_auth_failure_exits_20(self, capsys: pytest.CaptureFixture[str]) -> None:
+        """whoami_me_auth_failure [error]: /me 401 → exit 20 [session_api_failed]."""
+        respx.get("https://w.example/me").mock(
+            return_value=httpx.Response(401, json={"detail": "auth_invalid"})
+        )
+        rc = main(["--whoami", "--api-key", "k", "--server", "https://w.example"])
+        assert rc == 20
+        assert "[session_api_failed]" in capsys.readouterr().err
@@ -18,6 +18,8 @@ from ratatoskr.sessions import (
    SessionPage,
    create_session,
    endpoint_for_plane,
+    get_capabilities,
+    get_me,
    get_persona_state,
    list_agents,
    list_sessions,
@@ -896,3 +898,96 @@ class TestGetPersonaState:
            with pytest.raises(PersonaNotConfigured) as exc_info:
                await get_persona_state(client, "domari")
        assert exc_info.value.agent_id == "domari"
+
+
+class TestGetMe:
+    """docs/contracts/issues/2.contract.md FN get_me (slice: capabilities+me)."""
+
+    @respx.mock
+    async def test_happy_authenticated(self) -> None:
+        """happy_authenticated [happy,tracer]: 200 → parsed identity dict verbatim."""
+        respx.get("https://w.example/me").mock(
+            return_value=httpx.Response(
+                200,
+                json={
+                    "user_id": "alice",
+                    "scopes": ["conversations.read", "conversations.write"],
+                    "tier": "user",
+                    "key_id": "a1b2c3d4",
+                    "key_label": "alice phone",
+                },
+            )
+        )
+        async with httpx.AsyncClient(base_url="https://w.example") as client:
+            me = await get_me(client)
+        assert me["user_id"] == "alice"
+        assert me["tier"] == "user"
+        assert me["key_id"] == "a1b2c3d4"
+        assert me["scopes"] == ["conversations.read", "conversations.write"]
+
+    @respx.mock
+    async def test_anonymous_dev_mode(self) -> None:
+        """anonymous_dev_mode: 200 anonymous shape → dict with tier=anonymous."""
+        respx.get("https://w.example/me").mock(
+            return_value=httpx.Response(
+                200,
+                json={
+                    "user_id": "anonymous",
+                    "scopes": ["conversations.read"],
+                    "tier": "anonymous",
+                },
+            )
+        )
+        async with httpx.AsyncClient(base_url="https://w.example") as client:
+            me = await get_me(client)
+        assert me["tier"] == "anonymous"
+        assert "key_id" not in me  # optional fields omitted, not null
+
+    @respx.mock
+    async def test_401_raises_session_api_failed(self) -> None:
+        """401_raises [error]: bad/absent key → SessionApiFailed(status=401)."""
+        respx.get("https://w.example/me").mock(
+            return_value=httpx.Response(401, json={"detail": "auth_invalid"})
+        )
+        async with httpx.AsyncClient(base_url="https://w.example") as client:
+            with pytest.raises(SessionApiFailed) as exc:
+                await get_me(client)
+        assert exc.value.status == 401
+
+
+class TestGetCapabilities:
+    """docs/contracts/issues/2.contract.md FN get_capabilities (slice: capabilities+me)."""
+
+    @respx.mock
+    async def test_happy(self) -> None:
+        """happy [happy]: 200 → ephemeral_templates dict verbatim."""
+        respx.get("https://w.example/capabilities").mock(
+            return_value=httpx.Response(
+                200,
+                json={
+                    "ephemeral_templates": {
+                        "echo": {
+                            "allowed_models": ["glm5-turbo", "glm4.7"],
+                            "default_model": "glm5-turbo",
+                            "system_prompt_max_bytes": 32768,
+                        }
+                    }
+                },
+            )
+        )
+        async with httpx.AsyncClient(base_url="https://w.example") as client:
+            caps = await get_capabilities(client)
+        echo = caps["ephemeral_templates"]["echo"]
+        assert echo["default_model"] == "glm5-turbo"
+        assert echo["system_prompt_max_bytes"] == 32768
+
+    @respx.mock
+    async def test_non_200_raises(self) -> None:
+        """non_200_raises [error]: 500 → SessionApiFailed(status=500)."""
+        respx.get("https://w.example/capabilities").mock(
+            return_value=httpx.Response(500, content=b"boom")
+        )
+        async with httpx.AsyncClient(base_url="https://w.example") as client:
+            with pytest.raises(SessionApiFailed) as exc:
+                await get_capabilities(client)
+        assert exc.value.status == 500
@@ -1052,7 +1052,7 @@ wheels = [

 [[package]]
 name = "ratatoskr"
-version = "0.18.7"
+version = "0.18.8"
 source = { editable = "." }
 dependencies = [
    { name = "httpx" },