diff --git a/src/lembas/api/chats.py b/src/lembas/api/chats.py
index b8722e3..af578d6 100644
--- a/src/lembas/api/chats.py
+++ b/src/lembas/api/chats.py
@@ -55,6 +55,11 @@ KEEPALIVE_AFTER = 15.0
 # better than four hundred rows nobody meant to write.
 MAX_QUEUED = 10
 
+# How many things one chat may have switched off. There are a dozen families and
+# sixty skills at most, so this is not a limit anybody reaches by hand -- it is
+# there so a crafted POST cannot grow the column without bound.
+MAX_SCOPE_KEYS = 200
+
 
 def _owned_chat(db: DBSession, chat_id: str, user_id: str) -> Chat:
     chat = db.get(Chat, chat_id)
@@ -135,10 +140,19 @@ def _new_chat(
     if profile is not None and agent_mode.strip() in agent_policy.MODES:
         chat.agent_mode = agent_mode.strip()
     # After the model's defaults, so choosing one on the new-chat screen wins
-    # over the administrator's. Empty means "whatever the model said", not
-    # "none" -- clearing it is what the blank option on an existing chat does.
+    # over the administrator's.
+    #
+    # `"off"` is a sentinel, and it has to be: `reasoning_effort` arrives as
+    # `Form("")`, so an absent field and an empty one are indistinguishable --
+    # the FastAPI trap this codebase has already been bitten by once. With
+    # `value=""` on the off option, the reader would pick "off", the value would
+    # fall out of EFFORTS, the model's default seeded above would stay, and they
+    # would silently get "high". The picker shows what will be sent, so the two
+    # have to agree.
     wanted_effort = reasoning_effort.strip().lower()
-    if wanted_effort in chat_service.EFFORTS:
+    if wanted_effort == "off":
+        chat.params_json = {k: v for k, v in chat.params_json.items() if k != "reasoning_effort"}
+    elif wanted_effort in chat_service.EFFORTS:
         chat.params_json = {**chat.params_json, "reasoning_effort": wanted_effort}
     db.add(chat)
     db.commit()
@@ -518,6 +532,54 @@ async def attach_base(
     )
 
 
+@router.post("/{chat_id}/scope")
+async def set_scope(
+    db: Db,
+    user: RequiredUser,
+    chat_id: str,
+    kind: str = Form(""),
+    name: str = Form(""),
+    on: bool = Form(False),
+) -> Response:
+    """Turn one thing this chat may use on or off. **Narrowing only.**
+
+    Nothing here widens anything. `resolve_tools` applies this *after* the
+    model's capabilities, the reader's permissions and the instance
+    configuration, so a crafted POST turning something on reaches a tool those
+    gates have already removed -- there is a test for exactly that.
+
+    On is stored by **removing** the key rather than by writing True, so absent
+    stays the single representation of "on" and the column cannot grow a row per
+    family per chat. Bounded, so a crafted request cannot grow it either.
+
+    JSON reassignment rather than mutation: a plain dict assignment into a JSON
+    column is not detected.
+    """
+    chat = _owned_chat(db, chat_id, user.id)
+    bucket = {"family": "families", "skill": "skills"}.get(kind.strip())
+    wanted = name.strip()[:64]
+    if bucket is None or not wanted:
+        raise HTTPException(status.HTTP_400_BAD_REQUEST, "Say what to turn on or off.")
+
+    scope = dict(chat.scope_json or {})
+    entries = dict(scope.get(bucket) or {})
+    if on:
+        entries.pop(wanted, None)
+    else:
+        if len(entries) >= MAX_SCOPE_KEYS:
+            raise HTTPException(status.HTTP_409_CONFLICT, "Too many things switched off.")
+        entries[wanted] = False
+
+    if entries:
+        scope[bucket] = entries
+    else:
+        scope.pop(bucket, None)
+    chat.scope_json = scope
+    db.commit()
+
+    return Response(status_code=status.HTTP_204_NO_CONTENT)
+
+
 @router.post("/{chat_id}/keep")
 async def keep_chat(db: Db, user: RequiredUser, chat_id: str) -> Response:
     """Stop a temporary chat being temporary.
@@ -1373,20 +1435,33 @@ async def update_chat(request: Request, db: Db, user: RequiredUser, chat_id: str
             **_clean_params(**{k: str(v) for k, v in submitted_params.items()}),
         }
 
-    # Not a number, so it cannot go through _PARAM_RANGES. Empty means clear it,
-    # the same as every other parameter here; anything that is not one of the
-    # three is ignored rather than refused, so a typo does not cost a message.
+    # Not a number, so it cannot go through _PARAM_RANGES. `"off"` and empty
+    # both clear it -- the sentinel because that is what the picker sends now,
+    # empty because anything still posting the old value must keep working.
+    # Anything that is neither is ignored rather than refused, so a typo does
+    # not cost a message.
     if "reasoning_effort" in form:
         if not allowed.get("chat.params"):
             raise HTTPException(
                 status.HTTP_403_FORBIDDEN, "You may not change sampling parameters."
             )
         wanted = str(form["reasoning_effort"]).strip().lower()
-        if not wanted:
+        if not wanted or wanted == "off":
             chat.params_json = {**(chat.params_json or {}), "reasoning_effort": None}
         elif wanted in chat_service.EFFORTS:
             chat.params_json = {**(chat.params_json or {}), "reasoning_effort": wanted}
 
+    # Switching model re-seeds an effort that was never chosen, so "what the
+    # picker shows is what is sent" stays true afterwards. Only when the key is
+    # ABSENT: `None` means somebody cleared it deliberately, and resurrecting
+    # that would make "off" silently do nothing on the next model change.
+    if model_id and "reasoning_effort" not in (chat.params_json or {}):
+        seeded = ((match.params_json if match is not None else None) or {}).get(
+            "reasoning_effort"
+        )
+        if seeded in chat_service.EFFORTS:
+            chat.params_json = {**(chat.params_json or {}), "reasoning_effort": seeded}
+
     db.commit()
     return Response(status_code=status.HTTP_204_NO_CONTENT)
 
diff --git a/src/lembas/api/pages.py b/src/lembas/api/pages.py
index 7038006..b0115eb 100644
--- a/src/lembas/api/pages.py
+++ b/src/lembas/api/pages.py
@@ -62,11 +62,87 @@ def _chat_context(db: DBSession, user: User, chat: Chat | None) -> dict:
         # command, the control and the request builder cannot disagree about
         # what is a valid effort.
         "efforts": chat_service.EFFORTS,
+        # What the picker shows, and what `build_request` will send. One
+        # resolver so the two cannot disagree.
+        "resolved_effort": chat_service.resolved_effort(chat) if chat else "",
+        **_scope_context(db, user, chat),
         **_agent_context(db, user, chat),
         **audio_service.template_flags(db, user),
     }
 
 
+def _scope_context(db: DBSession, user: User, chat: Chat | None) -> dict:
+    """What this chat may use, for the menu that narrows it.
+
+    Only for an existing chat: there is no row to write to before one exists,
+    and a menu whose choices went nowhere would be worse than no menu. The
+    families listed are the ones actually offered *right now*, so the menu never
+    shows a switch for something the model, the reader's permissions or the
+    instance has already ruled out -- turning that on would do nothing, since
+    `resolve_tools` applies this after the gates.
+    """
+    from lembas.services import tool_labels
+    from lembas.services import tools as tools_service
+    from lembas.services.library import skills as skills_service
+
+    if chat is None:
+        return {"scope_families": [], "scope_skills": []}
+
+    off = tools_service.scoped_off(chat)
+    skills_off = tools_service.scoped_skills_off(chat)
+
+    # Gates rather than tool names: `notes` is one switch, not five, which is
+    # the same reasoning the per-model capability checkboxes carry.
+    seen: dict[str, str] = {}
+    for tool in tools_service.resolve_tools(db, chat, user).defs:
+        seen.setdefault(tools_service.gate_of(tool.family), tool.name)
+    # Anything already switched off is absent from the offered set, so it has to
+    # be put back or there would be no way to turn it on again.
+    for gate in off:
+        seen.setdefault(gate, "")
+
+    families = [
+        {
+            "gate": gate,
+            "label": _GATE_LABELS.get(gate) or tool_labels.label_for(example) or gate,
+            "on": gate not in off,
+        }
+        for gate, example in sorted(seen.items())
+    ]
+
+    skills = []
+    if permissions.has(db, user, "library.use"):
+        skills = [
+            {
+                "name": skill.name,
+                "description": skill.description,
+                "on": skill.name not in skills_off,
+            }
+            for skill in skills_service.enabled_for(db, user)
+        ]
+        for name in sorted(skills_off):
+            if name not in {s["name"] for s in skills}:
+                skills.append({"name": name, "description": "", "on": False})
+
+    return {"scope_families": families, "scope_skills": skills}
+
+
+# What a gate is called in the menu. A gate covers several tools, so no single
+# tool's label is the right name for it.
+_GATE_LABELS = {
+    "web_search": "Web search",
+    "fetch": "Fetching pages",
+    "knowledge": "Your knowledge library",
+    "notes": "Notes",
+    "memory": "Memory",
+    "skills": "Skills",
+    "ask": "Asking you questions",
+    "agent": "Running commands",
+    "custom": "Custom tools",
+    "mcp": "MCP servers",
+}
+
+
 def _agent_context(db: DBSession, user: User, chat: Chat | None) -> dict:
     """What the composer and the chat header need to know about agent chats.
 
diff --git a/src/lembas/db/models/chat.py b/src/lembas/db/models/chat.py
index 901d2ec..10d00c4 100644
--- a/src/lembas/db/models/chat.py
+++ b/src/lembas/db/models/chat.py
@@ -151,6 +151,12 @@ class Chat(UUIDPrimaryKey, Timestamps, Base):
     # message with a plan" -- `context_variables` is synchronous and on the
     # request path. A plan a model cannot see is a plan it cannot keep current.
     plan_message_id: Mapped[str | None] = mapped_column(String(32))
+    # What this chat has switched off, narrowing what it is already allowed.
+    # {"families": {"web_search": false}, "skills": {"weekly-report": false}}.
+    # **Absent means on**, for every key -- the same convention
+    # `McpServer.tool_overrides_json` uses, and for the same reason: two
+    # representations of "on" makes "why is this off?" unanswerable.
+    scope_json: Mapped[dict[str, Any]] = mapped_column(JSONDict, default=dict)
 
     # --- Compaction ----------------------------------------------------------
     # A summary of the turns up to `compacted_through_id`, sent in their place.
diff --git a/src/lembas/services/chat.py b/src/lembas/services/chat.py
index 69c81d9..e4e49a8 100644
--- a/src/lembas/services/chat.py
+++ b/src/lembas/services/chat.py
@@ -332,6 +332,25 @@ def build_request(
 EFFORTS = ("low", "medium", "high")
 
 
+def resolved_effort(chat) -> str:
+    """The effort this chat will actually send, or "" for none.
+
+    Its own value, and nothing else. The model's default is a **seed** applied
+    when the chat is created (`api/chats.py:_new_chat`) and on a model change,
+    and is deliberately not consulted here for two reasons. A chat's request
+    should be a function of the chat row alone -- the same rule that has PDF
+    text extracted once at upload and knowledge attachments copied. And a
+    fallback would break "off": `update_chat` stores `None` for a cleared
+    effort, a fallback would resurrect the model's default underneath it, and
+    the off option would silently do nothing.
+
+    The picker shows exactly this, which is the whole point of it existing:
+    "Effort: default" named no level and was true of nothing in particular.
+    """
+    value = (getattr(chat, "params_json", None) or {}).get("reasoning_effort")
+    return value if value in EFFORTS else ""
+
+
 def apply_effort(body: dict[str, Any], effort: str | None) -> None:
     """Put a chosen reasoning effort into a request body, in both forms."""
     if not effort or effort not in EFFORTS:
diff --git a/src/lembas/services/harness.py b/src/lembas/services/harness.py
index 5f86163..fe0254b 100644
--- a/src/lembas/services/harness.py
+++ b/src/lembas/services/harness.py
@@ -133,7 +133,11 @@ def context_variables(
         "memory_limit": str(memories_service.MAX_MEMORY_CHARS),
         "tool_names": _tool_names(offered),
         "memories": memories_service.block(db, user) if "memory" in families else "",
-        "skills": skills_service.index_block(db, user) if "skills" in families else "",
+        "skills": (
+            skills_service.index_block(db, user, exclude=tools_service.scoped_skills_off(chat))
+            if "skills" in families
+            else ""
+        ),
         "knowledge_bases": "",
         "document_names": "",
         "agent_target": "",
diff --git a/src/lembas/services/library/memories.py b/src/lembas/services/library/memories.py
index 6dcec30..6560df2 100644
--- a/src/lembas/services/library/memories.py
+++ b/src/lembas/services/library/memories.py
@@ -57,23 +57,45 @@ def get(db: DBSession, memory_id: str, user: User | None) -> Memory | None:
 
 
 def add(db: DBSession, *, owner: User, content: str, author: str = AUTHOR_MODEL) -> Memory:
-    """Record a fact. Raises ValueError when there is no room or nothing to say."""
+    """Record a fact. Raises ValueError when there is no room or nothing to say.
+
+    An exact repeat returns the record that already exists rather than making a
+    second one. The prompt asks the model to check before adding -- it is shown
+    every memory, so it can -- but the same preference saved four times in
+    slightly different words is the commonest failure here, and it is worse than
+    wasted tokens: it makes `memory_forget` ambiguous for every one of them.
+    Wording handles the near-duplicates; this handles the exact ones, which is
+    the half a prompt cannot be relied on for.
+    """
     content = " ".join((content or "").split())
     if not content:
         raise ValueError("A memory cannot be empty.")
+    content = content[:MAX_MEMORY_CHARS]
+
+    existing = db.scalars(
+        select(Memory).where(Memory.owner_id == owner.id, Memory.content == content)
+    ).first()
+    if existing is not None:
+        return existing
 
     count = db.scalar(
         select(func.count()).select_from(Memory).where(Memory.owner_id == owner.id)
     )
     if (count or 0) >= MAX_RECORDS:
+        # Deliberately does NOT say "remove one first". Past MAX_TOTAL_CHARS the
+        # injected block is truncated, so the model is not shown every memory
+        # and would be choosing blind -- and deleting the wrong one is not
+        # something anybody finds out about.
         raise ValueError(
-            f"There are already {MAX_RECORDS} memories. Remove one first, or put "
-            f"this in a note instead."
+            f"There are already {MAX_RECORDS} memories, which is the limit, so "
+            f"nothing was saved. Do not remove one to make room — you are not "
+            f"shown all of them and would be guessing. Say that the limit has "
+            f"been reached, and put this in a note instead."
         )
 
     memory = Memory(
         owner_id=owner.id,
-        content=content[:MAX_MEMORY_CHARS],
+        content=content,
         author=author if author in (AUTHOR_USER, AUTHOR_MODEL) else AUTHOR_MODEL,
     )
     db.add(memory)
diff --git a/src/lembas/services/library/skills.py b/src/lembas/services/library/skills.py
index 22c99dd..5acd45b 100644
--- a/src/lembas/services/library/skills.py
+++ b/src/lembas/services/library/skills.py
@@ -23,6 +23,7 @@ from __future__ import annotations
 
 import logging
 import re
+from collections.abc import Iterable
 
 from sqlalchemy import select
 from sqlalchemy.orm import Session as DBSession
@@ -72,18 +73,34 @@ def by_name(db: DBSession, name: str, user: User | None) -> Skill | None:
     return db.scalar(visible(db, user).where(Skill.name == slugify(name)))
 
 
-def enabled_for(db: DBSession, user: User | None) -> list[Skill]:
-    """Skills that should appear in the index, oldest first for a stable order."""
+def enabled_for(
+    db: DBSession, user: User | None, *, exclude: Iterable[str] = ()
+) -> list[Skill]:
+    """Skills that should appear in the index, oldest first for a stable order.
+
+    `exclude` is what one chat has switched off by name -- a narrowing of what
+    the library already allows, never a widening of it.
+    """
     if user is None:
         return []
-    return list(
-        db.scalars(
-            visible(db, user)
-            .where(Skill.enabled.is_(True))
-            .order_by(Skill.name)
-            .limit(MAX_INDEX_SKILLS)
-        )
+    hidden = {slugify(name) for name in exclude}
+    rows = db.scalars(
+        visible(db, user)
+        .where(Skill.enabled.is_(True))
+        .order_by(Skill.name)
+        .limit(MAX_INDEX_SKILLS + len(hidden))
     )
+    return [skill for skill in rows if skill.name not in hidden][:MAX_INDEX_SKILLS]
+
+
+def count_enabled(db: DBSession, user: User | None, *, exclude: Iterable[str] = ()) -> int:
+    """How many skills are available here at all.
+
+    Zero is what withdraws `skill_get` and `skill_edit`: reading and improving
+    are meaningless with nothing to read, and a model told to "read one with
+    skill_get" above a list that is not there spends a round finding out.
+    """
+    return len(enabled_for(db, user, exclude=exclude))
 
 
 def search(db: DBSession, user: User | None, needle: str, *, limit: int = 10) -> list[Skill]:
@@ -199,9 +216,9 @@ def delete(db: DBSession, skill: Skill) -> None:
     db.commit()
 
 
-def index_block(db: DBSession, user: User | None) -> str:
+def index_block(db: DBSession, user: User | None, *, exclude: Iterable[str] = ()) -> str:
     """The one-line-per-skill listing that goes into the prompt."""
-    skills = enabled_for(db, user)
+    skills = enabled_for(db, user, exclude=exclude)
     if not skills:
         return ""
     return "\n".join(f"- {skill.name}: {skill.description}" for skill in skills)
diff --git a/src/lembas/services/prompts.py b/src/lembas/services/prompts.py
index 3cedcdf..c844221 100644
--- a/src/lembas/services/prompts.py
+++ b/src/lembas/services/prompts.py
@@ -801,7 +801,8 @@ BUILTIN: tuple[Fragment, ...] = (
             "would be tedious to work out again: a procedure, a decision and its reasons, "
             "a summary of a long document. Correct one with notes_edit when it turns out "
             "to be wrong, and remove it with notes_delete when it is no longer true — a "
-            "stale note is worse than no note."
+            "stale note is worse than no note. Anything short and durable about the "
+            "person themselves is a memory rather than a note."
         ),
     ),
     Fragment(
@@ -813,32 +814,58 @@ BUILTIN: tuple[Fragment, ...] = (
         variables=("memory_limit",),
         hint="Appears when memory_add and memory_forget are offered. What is "
         "remembered costs tokens on every request forever, which is why the "
-        "wording is about restraint.",
+        "wording is about restraint — and why it says to read what is already "
+        "there first: the same fact stored twice in different words costs the "
+        "window twice and makes either one ambiguous to remove afterwards.",
         default=(
             "- You can remember durable facts about this person — a preference, a "
             "constraint, a name, how they like to be addressed. Use memory_add for those: "
-            "one fact each, under {{memory_limit}} characters. Do not remember the details "
-            "of a single task, anything that will be untrue next month, or anything "
-            "secret — keys, passwords, or health details they have not asked you to keep. "
+            "one fact each, under {{memory_limit}} characters. Everything remembered is "
+            "already in this message, so read it before adding: saying the same thing "
+            "again in different words costs the window twice and makes either one hard "
+            "to remove afterwards. Do not remember the details of a single task, anything "
+            "that will be untrue next month, or anything secret — keys, passwords, or "
+            "health details they have not asked you to keep. Anything longer than a "
+            "sentence, or about the work rather than about them, does not belong here. "
             "When something you remembered turns out to be wrong, remove it with "
-            "memory_forget rather than adding a correction beside it."
+            "memory_forget, quoting it in full, rather than adding a correction beside it."
         ),
     ),
     Fragment(
         key="tool.skills",
-        label="Skills",
+        label="Skills: reading one",
         group=GROUP_TOOLS,
         order=240,
         families=("skills",),
-        hint="Appears when the skill tools are offered.",
+        requires=("skills",),
+        hint="Only once there is at least one skill. This used to be one "
+        "fragment gated on the family alone, so a person with no skills got "
+        "'the list below gives each one's name' above no list, and skill_get "
+        "in the tools array — which is exactly why models hunt for skills that "
+        "do not exist. The writing half is its own fragment below, because "
+        "that half is most useful precisely when there are none.",
         default=(
             "- Skills are procedures you have saved. The list below gives only each one's "
             "name and when to use it; read the full instructions with skill_get before "
-            "following one. If you work out a repeatable way to do something, save it with "
-            "skill_create. If following one shows it to be wrong or incomplete, improve it "
+            "following one. If following one shows it to be wrong or incomplete, improve it "
             "with skill_edit and say why — the previous version is kept and can be restored."
         ),
     ),
+    Fragment(
+        key="tool.skills_write",
+        label="Skills: saving one",
+        group=GROUP_TOOLS,
+        order=241,
+        families=("skills",),
+        hint="The other half, and deliberately NOT gated on there being any: "
+        "somebody with no skills is exactly who most needs to be told they can "
+        "save the first one.",
+        default=(
+            "- If you work out a repeatable way to do something you expect to be asked for "
+            "again, save it with skill_create. The description has to say when to use it, "
+            "since that is all you will see next time."
+        ),
+    ),
     # --- Context -------------------------------------------------------------
     Fragment(
         key="context.knowledge_scope",
@@ -864,11 +891,15 @@ BUILTIN: tuple[Fragment, ...] = (
         variables=("memories",),
         requires=("memories",),
         hint="The remembered facts themselves, injected whole on every turn. "
-        "Skipped entirely when there are none.",
+        "Skipped entirely when there are none. It used to say these 'still "
+        "apply', which nothing checks — and which taught a model to trust a "
+        "stale memory over what the person had just said.",
         default=(
             "### What you know about this person\n"
             "\n"
-            "The following was remembered in earlier conversations and still applies.\n"
+            "These were remembered in earlier conversations. If something here is "
+            "contradicted by what they say now, believe them and remove it with "
+            "memory_forget.\n"
             "\n"
             "{{memories}}"
         ),
diff --git a/src/lembas/services/tools.py b/src/lembas/services/tools.py
index 2d06bc4..5460dce 100644
--- a/src/lembas/services/tools.py
+++ b/src/lembas/services/tools.py
@@ -160,6 +160,11 @@ class ToolContext:
     # the decrypted credential. None everywhere else, which is what every agent
     # runner checks first. `generation` clears it when the reply ends.
     agent: Any = None
+    # Skills this chat has switched off, by name. Enforced in `_run_skill_get`
+    # and not only in the listing: without that the narrowing is advisory, since
+    # a model can name a skill it was never shown and the runner would fetch it
+    # anyway. Same rule as "what may be run is what was offered".
+    skills_off: frozenset[str] = field(default_factory=frozenset)
 
 
 @dataclass
@@ -530,18 +535,46 @@ async def _run_memory_add(context: ToolContext, args: dict[str, Any]) -> ToolOut
 
 
 async def _run_memory_forget(context: ToolContext, args: dict[str, Any]) -> ToolOutcome:
+    """Remove one memory, or refuse and say why.
+
+    Exact match first, then substring, and an ambiguous substring removes
+    nothing. This used to be a case-insensitive substring FIRST-match delete
+    with nothing warning about it, so `memory_forget("coffee")` against "Drinks
+    coffee black" and "Allergic to coffee" silently deleted whichever was older
+    -- a wrong deletion nobody would ever find out about, from a tool whose
+    description invited exactly the short fragment that misfires.
+
+    Exact-first is not a nicety: without it, quoting a memory in full still
+    fails whenever that text happens to be a substring of another one.
+    """
     wanted = str(args.get("content") or "").strip().lower()
     with session_scope() as db:
         user = db.get(User, context.owner_id)
         records = memories_service.all_for(db, user)
-        match = next((m for m in records if wanted and wanted in m.content.lower()), None)
-        if match is None:
+        if not wanted:
+            return ToolOutcome(
+                "Say which memory to remove, quoting its text.",
+                {"name": "memory_forget", "status": "error", "error": "Nothing given."},
+            )
+
+        exact = [m for m in records if m.content.strip().lower() == wanted]
+        matches = exact or [m for m in records if wanted in m.content.lower()]
+
+        if not matches:
             return ToolOutcome(
                 "No memory matches that. The full list is in the prompt already.",
                 {"name": "memory_forget", "status": "error", "error": "No match."},
             )
-        content = match.content
-        memories_service.delete(db, match)
+        if len(matches) > 1:
+            listed = "\n".join(f"- {m.content}" for m in matches[:10])
+            return ToolOutcome(
+                f"That matches {len(matches)} memories, so nothing was removed. "
+                f"Quote the whole text of the one you mean:\n{listed}",
+                {"name": "memory_forget", "status": "error", "error": "Ambiguous."},
+            )
+
+        content = matches[0].content
+        memories_service.delete(db, matches[0])
         return ToolOutcome(
             f"Forgotten: {content}",
             {"name": "memory_forget", "query": content, "status": "ok", "results": []},
@@ -554,6 +587,13 @@ async def _run_skill_get(context: ToolContext, args: dict[str, Any]) -> ToolOutc
     with session_scope() as db:
         user = db.get(User, context.owner_id)
         skill = skills_service.by_name(db, name, user)
+        # Enforced here and not only in the listing. Without this the per-chat
+        # narrowing is advisory: a model can name a skill it was never shown --
+        # from an earlier turn, from a note -- and the runner would fetch it.
+        if skill is not None and skill.name in {
+            skills_service.slugify(off) for off in context.skills_off
+        }:
+            skill = None
         if skill is None:
             return ToolOutcome(
                 f"There is no skill called {name!r}.",
@@ -778,9 +818,13 @@ REGISTRY: dict[str, ToolDef] = {
             family=FAMILY_MEMORY,
             description=(
                 "Remember one short, durable fact about the user — a preference, a "
-                "constraint, how they like to be addressed. You are shown every "
-                "memory on every turn, so keep them few and short, and never store "
-                "passwords, keys or anything else secret."
+                "constraint, a name, how they like to be addressed. Every memory is "
+                "put in front of you on every turn, up to a budget, so keep them few "
+                "and keep them short; text over the limit is shortened rather than "
+                "refused, and you are told. Check what is already remembered before "
+                "adding: a fact you have stored already in slightly different words "
+                "costs the same again and makes both of them harder to remove. Never "
+                "store a password, a key or anything else secret."
             ),
             parameters=_object(
                 {"content": {**_STRING, "description": "One fact, in one sentence."}},
@@ -793,10 +837,16 @@ REGISTRY: dict[str, ToolDef] = {
             name="memory_forget",
             family=FAMILY_MEMORY,
             description=(
-                "Remove a memory that has become wrong. Give enough of its text to "
-                "identify it."
+                "Remove a memory that is no longer true. Quote it in full — the "
+                "whole sentence as it appears in your prompt. A fragment that "
+                "matches more than one removes nothing and tells you which ones it "
+                "matched, because deleting the wrong memory is not something anyone "
+                "would find out about."
+            ),
+            parameters=_object(
+                {"content": {**_STRING, "description": "The memory's whole text."}},
+                ["content"],
             ),
-            parameters=_object({"content": _STRING}, ["content"]),
             run=_run_memory_forget,
             risk=RISK_WRITE,
         ),
@@ -1035,6 +1085,17 @@ def resolve_tools(db: DBSession, chat: Chat, user: User | None) -> ToolSet:
     # Resolved against what this reader may see, not against everything that
     # exists: a tool restricted to a group is not offered outside it.
     book = _book([*_row_defs(db, user), *_agent_defs(db, chat, user)])
+
+    # What this chat has switched off, applied AFTER the gates and never
+    # instead of them. A chat can only ever *narrow* what the model's
+    # capabilities, the reader's permissions and the instance configuration
+    # already allow -- exactly as `chat.knowledge_bases` narrows
+    # `knowledge_search` and can never widen it. A crafted request that turned
+    # something on here would still be reaching for a tool the gates had
+    # already removed.
+    off = scoped_off(chat)
+    empty_library = not skills_service.count_enabled(db, user, exclude=scoped_skills_off(chat))
+
     return ToolSet(
         tuple(
             tool
@@ -1042,10 +1103,42 @@ def resolve_tools(db: DBSession, chat: Chat, user: User | None) -> ToolSet:
             if _family_allowed(
                 tool.family, config=config, capabilities=capabilities, allowed=allowed
             )
+            and gate_of(tool.family) not in off
+            # Nothing to read and nothing to improve. Offering `skill_get` with
+            # no skills is what makes a model spend a round looking one up and
+            # being told it does not exist -- and `context.skills` already
+            # vanishes, so the prompt says "read one with skill_get" above a
+            # list that is not there. `skill_create` stays: writing the first
+            # one is exactly what somebody with none needs.
+            and not (empty_library and tool.name in _NEEDS_A_SKILL)
         )
     )
 
 
+# Skills tools that are meaningless with an empty library.
+_NEEDS_A_SKILL = frozenset({"skill_get", "skill_edit"})
+
+
+def scoped_off(chat: Chat | None) -> frozenset[str]:
+    """Gates this chat has switched off. **Absent means on**, always.
+
+    One representation of "on" -- the key not being there -- so that "why is
+    this off?" has one answer rather than two.
+    """
+    if chat is None:
+        return frozenset()
+    wanted = (getattr(chat, "scope_json", None) or {}).get("families") or {}
+    return frozenset(str(name) for name, on in wanted.items() if on is False)
+
+
+def scoped_skills_off(chat: Chat | None) -> frozenset[str]:
+    """Individual skills this chat has switched off, by name."""
+    if chat is None:
+        return frozenset()
+    wanted = (getattr(chat, "scope_json", None) or {}).get("skills") or {}
+    return frozenset(str(name) for name, on in wanted.items() if on is False)
+
+
 def enabled_tools(db: DBSession, chat: Chat, user: User | None) -> list[dict[str, Any]]:
     """The tool schemas to offer for this chat.
 
@@ -1070,6 +1163,7 @@ def context_for(
         owner_id=user.id if user else "",
         search_config=settings_store.search(db),
         base_ids=[base.id for base in chat.knowledge_bases] if chat is not None else [],
+        skills_off=scoped_skills_off(chat),
         tools=tools.by_name if tools is not None else None,
         interaction_timeout=float(settings_store.agents(db)["approval_timeout"]),
     )
diff --git a/src/lembas/web/static/css/app.css b/src/lembas/web/static/css/app.css
index fa9ceec..7268f22 100644
--- a/src/lembas/web/static/css/app.css
+++ b/src/lembas/web/static/css/app.css
@@ -1053,6 +1053,27 @@ body.is-resizing .terminal__screen { pointer-events: none; }
   right: auto;
 }
 .picker__menu--compact { width: min(18rem, calc(100vw - var(--sp-8))); padding: var(--sp-1); }
+
+/* "What this chat can use": a list of switches rather than a list of actions.
+   Wider than the compact menu because a skill's description has to fit, and
+   scrollable because a library of sixty skills would otherwise run off the top
+   of the window -- this menu opens upward. */
+.picker__menu--scope {
+  width: min(22rem, calc(100vw - var(--sp-8)));
+  max-height: min(26rem, 60vh);
+  overflow-y: auto;
+  padding: var(--sp-1);
+}
+.picker__lede {
+  margin: 0;
+  padding: var(--sp-2) var(--sp-3);
+  font-size: var(--text-xs);
+  color: var(--ink-faint);
+}
+/* A label, not a button, so several can be set without the menu closing --
+   ui.js closes on `[role="menuitem"]`, and these deliberately have none. */
+.picker__option--toggle { align-items: center; }
+.picker__option--toggle input { flex: none; margin: 0; }
 .picker__option-note {
   font-size: var(--text-xs);
   color: var(--ink-faint);
diff --git a/src/lembas/web/static/css/chat.css b/src/lembas/web/static/css/chat.css
index 04eb597..cd42aa1 100644
--- a/src/lembas/web/static/css/chat.css
+++ b/src/lembas/web/static/css/chat.css
@@ -846,25 +846,54 @@
   font-size: 0.95em;
 }
 
-/* Everything that acts on the message, on one line under it. It wraps rather
-   than scrolls: on a narrow window the context controls drop to their own row
-   and attach/send stay where the thumb expects them. */
+/* Everything that acts on the message, on one line under it. ONE line, always.
+
+   It used to wrap, and .composer__actions is last in the DOM with
+   margin-left:auto -- so the moment an agent chat added a connection, a
+   directory and a mode to this row, Send and the microphone were what dropped
+   to a second line. There are no media queries in this file, deliberately, and
+   the fix is not to add one: it is to say which child gives. */
 .composer__toolbar {
   display: flex;
   align-items: center;
-  flex-wrap: wrap;
-  gap: var(--sp-2);
-}
-.composer__tools { display: flex; align-items: center; gap: var(--sp-1); flex: none; }
-.composer__actions { display: flex; align-items: center; gap: var(--sp-1); margin-left: auto; }
-.composer__context {
-  display: flex;
-  align-items: center;
-  flex-wrap: wrap;
+  flex-wrap: nowrap;
   gap: var(--sp-2);
   min-width: 0;
 }
-.composer__agent { display: flex; align-items: center; gap: var(--sp-2); min-width: 0; }
+.composer__tools { display: flex; align-items: center; gap: var(--sp-1); flex: none; }
+
+/* Never shrinks, never wraps, always at the end of the line. This is where the
+   hand is going. */
+.composer__actions {
+  display: flex;
+  align-items: center;
+  gap: var(--sp-1);
+  flex: none;
+  margin-left: auto;
+}
+[data-effort] { flex: none; }
+
+/* The one thing allowed to give. It shrinks past its content and scrolls
+   sideways rather than wrapping. The scrollbar is hidden: the controls are
+   already visibly cut off, and a scrollbar under a --control-h row would change
+   the row's height, which is the one thing --control-h exists to prevent. */
+.composer__context {
+  display: flex;
+  align-items: center;
+  flex-wrap: nowrap;
+  gap: var(--sp-2);
+  flex: 1 1 auto;
+  min-width: 0;
+  overflow-x: auto;
+  scrollbar-width: none;
+}
+.composer__context::-webkit-scrollbar { display: none; }
+.composer__agent { display: flex; align-items: center; gap: var(--sp-2); flex-wrap: nowrap; }
+
+/* Floors, not fixed widths: a select narrower than this shows no text at all,
+   which is worse than the scrolling it was avoiding. */
+.composer__context .select { flex: 0 1 auto; min-width: 6rem; }
+/* `.segmented` already declares flex: none further down, where it is defined. */
 
 /* Round, and the same size as each other: attach and send read as one pair
    bracketing the row. */
@@ -872,7 +901,12 @@
 
 /* The directory, on a new chat. Monospace because it is a path, and it grows
    to fit rather than being pinned to a width that truncates every real one. */
-.composer__dir { max-width: 16rem; font-family: var(--font-mono); font-weight: 400; }
+.composer__dir {
+  flex: 0 1 16rem;
+  min-width: 5rem;
+  font-family: var(--font-mono);
+  font-weight: 400;
+}
 .composer__dir-path { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
 
 .composer__hint {
diff --git a/src/lembas/web/static/js/commands.js b/src/lembas/web/static/js/commands.js
index c50b6b3..a2dde4e 100644
--- a/src/lembas/web/static/js/commands.js
+++ b/src/lembas/web/static/js/commands.js
@@ -37,6 +37,9 @@
   /* --- Shortcuts ---------------------------------------------------------- */
   var SHORTCUTS = [
     { keys: "Ctrl/⌘ + K", what: "Open the command menu" },
+    { keys: "Ctrl/⌘ + Enter", what: "Send, from anywhere on the page" },
+    { keys: "Alt + M", what: "Dictate" },
+    { keys: "Alt + R", what: "Read the last reply aloud" },
     { keys: "Alt + 1 … 4", what: "Manual, Edit, Auto, Plan" },
     { keys: "Alt + T", what: "Terminal" },
     { keys: "Alt + I", what: "Inspector" },
@@ -74,7 +77,7 @@
     {
       name: "effort",
       summary: "How hard a reasoning model should think",
-      argument: "low | medium | high",
+      argument: "low | medium | high | off",
       /* Offered wherever there is a model, not only where the control is.
          `available()` filters `find()` and `run()` as well as the menu, so a
          command hidden here is not merely unlisted -- typing it in full stops
@@ -216,21 +219,25 @@
     var wanted = (rest || "").trim().toLowerCase();
     if (!wanted) {
       return note(
-        select.value
-          ? "Effort is " + select.value + ". /effort low, medium, high, or default."
-          : "Effort is whatever the model does by default. Try low, medium or high."
+        EFFORTS.indexOf(select.value) === -1
+          ? "No effort is being sent. Try low, medium or high."
+          : "Effort is " + select.value + ". /effort low, medium, high, or off."
       );
     }
-    if (wanted === "default" || wanted === "none") wanted = "";
-    else if (EFFORTS.indexOf(wanted) === -1) {
-      return note("“" + wanted + "” is not an effort. Try low, medium or high.", "error");
+    /* "off" is the option's real value, not an empty string: the new-chat form
+       cannot tell an absent field from an empty one, so the picker sends a
+       sentinel and this has to match it. "default" and "none" still work,
+       because somebody's fingers will type them. */
+    if (wanted === "default" || wanted === "none") wanted = "off";
+    else if (wanted !== "off" && EFFORTS.indexOf(wanted) === -1) {
+      return note("“" + wanted + "” is not an effort. Try low, medium, high or off.", "error");
     }
     select.value = wanted;
     select.dispatchEvent(new Event("change", { bubbles: true }));
     note(
-      wanted
-        ? "Effort set to " + wanted + "."
-        : "Effort cleared; the model decides."
+      wanted === "off"
+        ? "Effort cleared; nothing is sent."
+        : "Effort set to " + wanted + "."
     );
   }
 
@@ -467,8 +474,51 @@
       return;
     }
 
+    /* Send, from anywhere on the page.
+
+       Enter already sends, but only with the caret inside the box (app.js), and
+       deliberately not at all on a touch device. This covers both: after
+       clicking a message to copy it, after using the model picker, after
+       answering an approval card, or with a hardware keyboard on a tablet.
+
+       Never Stop. Send and Stop are the same element, so Ctrl+Enter meaning
+       "abandon the reply" would be a trap -- and Esc already stops. */
+    if ((event.ctrlKey || event.metaKey) &&
+        (event.code === "Enter" || event.code === "NumpadEnter")) {
+      var action = el("[data-composer-action]");
+      var box = el("[data-composer-input]");
+      if (action && action.dataset.composerAction === "send" && box && box.value.trim()) {
+        event.preventDefault();
+        action.click();
+      }
+      return;
+    }
+
     if (!event.altKey || event.ctrlKey || event.metaKey) return;
 
+    /* Dictation and read-aloud both work by clicking the button that already
+       does the job, so audio.js keeps its one delegated click listener and
+       there is no second copy of the recording state machine. Alt+M rather than
+       Alt+D: Alt+D is the address bar in Chrome and Firefox. */
+    if (event.code === "KeyM") {
+      var mic = el("[data-mic]");
+      if (mic) {
+        event.preventDefault();
+        mic.click();
+      }
+      return;
+    }
+    if (event.code === "KeyR") {
+      var speakers = document.querySelectorAll("#thread .msg--assistant [data-speak]");
+      if (speakers.length) {
+        event.preventDefault();
+        /* A second press stops it: audio.js already toggles a message that is
+           speaking, so this costs nothing and is the obvious second press. */
+        speakers[speakers.length - 1].click();
+      }
+      return;
+    }
+
     if (event.code === "KeyT" && el("#terminal")) {
       event.preventDefault();
       return toggle("#terminal", "side");
diff --git a/src/lembas/web/templates/admin/model_detail.html b/src/lembas/web/templates/admin/model_detail.html
index 77f6e7d..47dbd84 100644
--- a/src/lembas/web/templates/admin/model_detail.html
+++ b/src/lembas/web/templates/admin/model_detail.html
@@ -107,7 +107,7 @@
     <div class="field">
       <label class="field__label" for="default-effort">Default reasoning effort</label>
       <select class="select" id="default-effort" name="default_effort">
-        <option value="">Whatever the model does</option>
+        <option value="">None — send nothing</option>
         {% for value in efforts %}
         <option value="{{ value }}"
                 {{ 'selected' if model.params_json.get('reasoning_effort') == value }}>
@@ -116,7 +116,12 @@
         {% endfor %}
       </select>
       <p class="field__hint">
-        Where new chats on this model start. Anyone can change it per chat with
+        A <em>seed</em>, not a per-request setting: it is copied onto a chat when
+        the chat is created and when somebody switches to this model, and from
+        then on the chat's own value is what is sent. Changing it here therefore
+        does nothing to chats that already exist. The composer's picker shows
+        whichever level is actually in force, so what somebody sees there is
+        what goes out. Anyone can change it per chat with
         <span class="mono">/effort</span>, and the control only appears on a
         model marked <strong>Reasoning</strong> above.
         <br>
diff --git a/src/lembas/web/templates/chat/_composer.html b/src/lembas/web/templates/chat/_composer.html
index 60d7ea2..0a87333 100644
--- a/src/lembas/web/templates/chat/_composer.html
+++ b/src/lembas/web/templates/chat/_composer.html
@@ -140,13 +140,100 @@
             </div>
           </div>
 
-          {# The same menu the `@` key opens, for anyone who would rather press
-             than type. It inserts the character and gets out of the way. #}
-          <button class="btn btn--icon composer__btn" type="button" data-mention-open
-                  aria-label="Mention a file or a document"
-                  title="Mention a file or a document">
-            {{ icon("at") }}
-          </button>
+          {% endif %}
+
+          {#
+            What this chat may use.
+
+            This slot used to be an `@` button that inserted the character and
+            got out of the way -- which the `@` key already does, from the
+            keyboard, without a button. Typing `@` is untouched; composer.js
+            recognises the token on its own and knows nothing about this menu.
+
+            The rows are `<label>`s wrapping a checkbox and deliberately carry
+            no `role="menuitem"`: ui.js closes a picker when a menuitem is
+            clicked, which is right for an action menu and wrong for a list of
+            switches you want to set several of. That is the whole reason this
+            needs no JavaScript at all.
+
+            The verb is on the CHECKBOX, not on the label and not on a form: the
+            element carrying `name` has to be the element carrying the request,
+            which is what tests/conftest.py:control_named exists to pin.
+
+            Only on an existing chat -- there is no row to write to before one
+            exists, and a switch that went nowhere is worse than no switch.
+          #}
+          {% set has_scope = chat and (scope_families or scope_skills) %}
+          {% if has_scope or can.get("files.upload") %}
+          <div class="picker picker--up" data-picker>
+            <button class="btn btn--icon composer__btn" type="button" data-picker-toggle
+                    aria-haspopup="menu" aria-expanded="false"
+                    aria-label="{{ 'What this chat can use' if has_scope else 'Mention a file' }}"
+                    title="{{ 'What this chat can use' if has_scope else 'Mention a file' }}">
+              {{ icon("sliders" if has_scope else "at") }}
+            </button>
+
+            <div class="picker__menu picker__menu--scope" data-picker-menu role="menu"
+                 hidden aria-label="What this chat can use">
+              {% if has_scope %}
+              <p class="picker__lede">
+                Switched off here only. Everything is on unless you say otherwise.
+              </p>
+              {% endif %}
+
+              {% if scope_families %}
+              <p class="picker__group">Tools</p>
+              {% for family in scope_families %}
+              <label class="picker__option picker__option--toggle">
+                <input type="checkbox" name="on" value="true"
+                       {{ 'checked' if family.on }}
+                       hx-post="/api/chats/{{ chat.id }}/scope" hx-swap="none"
+                       hx-vals='{"kind": "family", "name": "{{ family.gate }}"}'>
+                <span class="picker__option-body">
+                  <span class="picker__option-name">{{ family.label }}</span>
+                </span>
+              </label>
+              {% endfor %}
+              {% endif %}
+
+              {% if scope_skills %}
+              <p class="picker__group">Skills</p>
+              {% for skill in scope_skills %}
+              <label class="picker__option picker__option--toggle">
+                <input type="checkbox" name="on" value="true"
+                       {{ 'checked' if skill.on }}
+                       hx-post="/api/chats/{{ chat.id }}/scope" hx-swap="none"
+                       hx-vals='{"kind": "skill", "name": "{{ skill.name }}"}'>
+                <span class="picker__option-body">
+                  <span class="picker__option-name">{{ skill.name }}</span>
+                  {% if skill.description %}
+                  <span class="picker__option-note">{{ skill.description }}</span>
+                  {% endif %}
+                </span>
+              </label>
+              {% endfor %}
+              {% endif %}
+
+              {# The affordance the `@` button used to be, kept as one row so
+                 nothing is lost by replacing the button -- and it is what this
+                 menu holds on a chat that does not exist yet, where there is no
+                 scope to narrow.
+
+                 This one DOES carry role="menuitem", unlike the switches above:
+                 it is an action, so ui.js closing the picker after it is
+                 exactly right. #}
+              {% if can.get("files.upload") %}
+              <button class="picker__option" type="button" role="menuitem"
+                      data-mention-open>
+                {{ icon("at", "icon--sm") }}
+                <span class="picker__option-body">
+                  <span class="picker__option-name">Mention a file or a document</span>
+                  <span class="picker__option-note">Or just type @</span>
+                </span>
+              </button>
+              {% endif %}
+            </div>
+          </div>
           {% endif %}
         </div>
 
@@ -256,9 +343,23 @@
                 form="chat-params-form"
                 hx-patch="/api/chats/{{ chat.id }}" hx-swap="none"
                 {% endif %}>
-          {% set chosen = chat.params_json.get('reasoning_effort') if chat
+          {#
+            It shows the level actually in force, never the word "default".
+
+            On an existing chat that is `resolved_effort`, which is the chat's
+            own value and nothing else -- `build_request` reads the same field,
+            so what is shown is what is sent, by construction. Before there is a
+            chat it is the model's configured level, which `_new_chat` seeds
+            onto the row, so the same holds.
+
+            "off" is a sentinel and NOT an empty value. `start_chat` declares
+            `reasoning_effort: str = Form("")`, so absent and empty are
+            indistinguishable there -- with `value=""` the reader would pick off
+            and silently get the model's default.
+          #}
+          {% set chosen = resolved_effort if chat
                           else (current_model.params_json or {}).get('reasoning_effort') %}
-          <option value="">Effort: default</option>
+          <option value="off" {{ 'selected' if chosen not in efforts }}>Effort: off</option>
           {% for value in efforts %}
           <option value="{{ value }}" {{ 'selected' if chosen == value }}>
             Effort: {{ value }}
diff --git a/tests/test_agent_tools.py b/tests/test_agent_tools.py
index f2850da..e6dc964 100644
--- a/tests/test_agent_tools.py
+++ b/tests/test_agent_tools.py
@@ -686,7 +686,7 @@ async def test_an_ordinary_chat_is_told_none_of_it(db, user_id, machine):
 
 
 async def test_an_agent_chat_is_told_its_real_round_budget(db, user_id, machine):
-    """MAX_ROUNDS is three. An agent chat gets forty, and telling it three would
+    """MAX_ROUNDS is one. An agent chat gets hundreds, and telling it one would
     be a false fact about its own budget on every turn."""
     from lembas.services import harness
 
diff --git a/tests/test_chat.py b/tests/test_chat.py
index a69c9ee..d2320ce 100644
--- a/tests/test_chat.py
+++ b/tests/test_chat.py
@@ -699,3 +699,79 @@ def test_the_sidebar_shows_an_unread_dot(client: TestClient, db, registered, mak
     page = client.get("/chat").text
     assert f'id="unread-{chat_id}" class="unread-dot"' in page
     assert 'hx-get="/api/chats/unread"' in page
+
+
+# --- The composer's one row --------------------------------------------------
+def test_the_send_button_is_the_last_thing_in_the_toolbar(client: TestClient, db, registered):
+    """What the layout depends on. `.composer__actions` is pushed right by
+    `margin-left: auto` and refuses to shrink, and both only work while it is
+    the last child -- when the row wrapped instead, it was the last child that
+    dropped to a second line, so an agent chat pushed Send and the microphone
+    off the row entirely."""
+    _add_connection(db)
+    html = client.get("/chat").text
+    toolbar = html.split('class="composer__toolbar"', 1)[1]
+
+    assert 'class="composer__actions"' in toolbar
+    assert toolbar.index("composer__actions") > toolbar.index("composer__tools")
+    assert "data-composer-action" in toolbar
+
+
+def test_the_agent_controls_shrink_rather_than_pushing_send_off_the_row(
+    client: TestClient, db, registered
+):
+    """They live in `.composer__context`, which is the only flex child allowed
+    to shrink and scroll. Anything moved out of it stops shrinking and starts
+    pushing Send onto a second line again -- which is what this whole row was
+    rearranged to stop."""
+    from lembas.db.models import SshProfile
+    from lembas.services import settings_store
+
+    _add_connection(db)
+    settings_store.update(db, {"enabled": True}, key=settings_store.AGENTS)
+    db.add(
+        SshProfile(
+            owner_id=_user_id(db),
+            name="Test box",
+            host="127.0.0.1",
+            port=22,
+            username="t",
+            host_key="k",
+            host_fingerprint="f",
+            default_dir="/work",
+        )
+    )
+    db.commit()
+
+    html = client.get("/chat").text
+    if "composer__context" not in html:
+        pytest.skip("agent chats are unavailable here")
+
+    # The three that appear when Agent is chosen sit between the start of
+    # `.composer__context` and the start of `.composer__actions` -- which is
+    # what puts them inside the one child that is allowed to give, and keeps
+    # the actions last.
+    opens = html.index('class="composer__context"')
+    actions = html.index('class="composer__actions"')
+    for control in ("ssh_profile_id", "data-dir-browse", 'name="agent_mode"'):
+        assert opens < html.index(control) < actions, control
+
+
+def test_the_chat_stylesheet_has_no_media_queries(client: TestClient):
+    """A stated design constraint, pinned so nobody 'fixes' a layout with a
+    breakpoint later. The composer fits at every width by saying which child
+    gives, not by rearranging itself at a threshold."""
+    from pathlib import Path
+
+    import lembas
+
+    css = Path(lembas.__file__).parent / "web/static/css/chat.css"
+    assert "@media" not in css.read_text()
+
+
+def _user_id(db):
+    from sqlalchemy import select
+
+    from lembas.db.models import User
+
+    return db.scalar(select(User.id))
diff --git a/tests/test_chat_scope.py b/tests/test_chat_scope.py
new file mode 100644
index 0000000..acfda3c
--- /dev/null
+++ b/tests/test_chat_scope.py
@@ -0,0 +1,284 @@
+"""What one chat may use, and the rule that it can only ever be less.
+
+The security-shaped test here is `test_a_chat_cannot_widen_what_it_was_not_given`.
+The scope is applied inside `resolve_tools` *after* the model's capabilities,
+the reader's permissions and the instance configuration, so a crafted POST
+turning something on reaches a tool those gates have already removed. Asserting
+that against the UI path alone would prove nothing, so it is asserted against a
+directly-written column.
+"""
+
+from __future__ import annotations
+
+import pytest
+from fastapi.testclient import TestClient
+
+from lembas.db.models import Chat, Connection, Model, User
+from lembas.services import settings_store
+from lembas.services import tools as tools_service
+from lembas.services.library import skills as skills_service
+
+
+@pytest.fixture
+def chat(db, user_id):
+    connection = Connection(name="c", base_url="http://127.0.0.1:1", api_key_encrypted="")
+    db.add(connection)
+    db.commit()
+    db.add(Model(connection_id=connection.id, model_id="m", capabilities_json={"tools": True}))
+    db.commit()
+    row = Chat(user_id=user_id, model_id="m", connection_id=connection.id)
+    db.add(row)
+    db.commit()
+    return row
+
+
+def _names(db, chat, user) -> set[str]:
+    return set(tools_service.resolve_tools(db, chat, user).by_name)
+
+
+# --- The route ------------------------------------------------------------------
+def test_switching_a_family_off_writes_it_to_the_row(client: TestClient, db, chat, registered):
+    response = client.post(
+        f"/api/chats/{chat.id}/scope", data={"kind": "family", "name": "web_search"}
+    )
+    assert response.status_code == 204
+
+    db.expire_all()
+    assert db.get(Chat, chat.id).scope_json["families"]["web_search"] is False
+
+
+def test_switching_it_back_on_removes_the_key(client: TestClient, db, chat, registered):
+    """On is stored by *removing* the key, so absent stays the single
+    representation of on and the column cannot grow a row per family per chat."""
+    client.post(f"/api/chats/{chat.id}/scope", data={"kind": "family", "name": "notes"})
+    client.post(
+        f"/api/chats/{chat.id}/scope",
+        data={"kind": "family", "name": "notes", "on": "true"},
+    )
+
+    db.expire_all()
+    assert "families" not in db.get(Chat, chat.id).scope_json
+
+
+def test_the_route_refuses_a_kind_it_does_not_know(client: TestClient, chat, registered):
+    response = client.post(
+        f"/api/chats/{chat.id}/scope", data={"kind": "everything", "name": "x"}
+    )
+    assert response.status_code == 400
+
+
+def test_the_route_refuses_the_wrong_verb(client: TestClient, chat, registered):
+    """The half of `tests/test_agent_mode.py`'s lesson that actually caught the
+    bug: a control wired to a method a route does not serve fails silently."""
+    assert client.get(f"/api/chats/{chat.id}/scope").status_code == 405
+
+
+def test_somebody_elses_chat_is_not_reachable(client: TestClient, db, chat, registered):
+    from lembas.security.passwords import hash_password
+
+    other = User(name="Sam", email="s@shire.test", password_hash=hash_password("secret123"))
+    db.add(other)
+    db.commit()
+    chat.user_id = other.id
+    db.commit()
+
+    response = client.post(
+        f"/api/chats/{chat.id}/scope", data={"kind": "family", "name": "notes"}
+    )
+    assert response.status_code == 404
+
+
+# --- What it does to the offer ------------------------------------------------------
+def test_a_family_switched_off_is_not_offered(db, chat, user_id):
+    settings_store.update(db, {"enabled": True}, key=settings_store.SEARCH)
+    user = db.get(User, user_id)
+    assert "web_search" in _names(db, chat, user)
+
+    chat.scope_json = {"families": {"web_search": False}}
+    db.commit()
+
+    assert "web_search" not in _names(db, chat, user)
+
+
+def test_switching_a_gate_off_takes_every_tool_in_it(db, chat, user_id):
+    """A gate is one switch, not five. `notes` covers search, get, create, edit
+    and delete -- which is the same reasoning the per-model capability
+    checkboxes carry."""
+    user = db.get(User, user_id)
+    chat.scope_json = {"families": {"notes": False}}
+    db.commit()
+
+    offered = _names(db, chat, user)
+    assert not [name for name in offered if name.startswith("notes_")]
+
+
+def test_a_chat_cannot_widen_what_it_was_not_given(db, chat, user_id):
+    """The one that matters. Scope is applied AFTER the gates and never instead
+    of them, so writing `True` into the column reaches a tool the model's
+    capabilities had already removed."""
+    user = db.get(User, user_id)
+    model = db.scalar(tools_service.select(Model))
+    model.capabilities_json = {"tools": True, "tool_notes": False}
+    chat.scope_json = {"families": {"notes": True}}
+    db.commit()
+
+    assert "notes_search" not in _names(db, chat, user)
+
+
+def test_an_unknown_family_in_the_column_changes_nothing(db, chat, user_id):
+    user = db.get(User, user_id)
+    before = _names(db, chat, user)
+    chat.scope_json = {"families": {"not-a-family": False}}
+    db.commit()
+
+    assert _names(db, chat, user) == before
+
+
+# --- Skills -------------------------------------------------------------------------
+@pytest.fixture
+def skill(db, user_id):
+    return skills_service.create(
+        db,
+        owner=db.get(User, user_id),
+        name="weekly-report",
+        description="When asked for the weekly report.",
+        body="Do the thing.",
+    )
+
+
+def test_a_skill_switched_off_leaves_the_index(db, chat, user_id, skill):
+    user = db.get(User, user_id)
+    assert "weekly-report" in skills_service.index_block(db, user)
+    assert "weekly-report" not in skills_service.index_block(
+        db, user, exclude=["weekly-report"]
+    )
+
+
+def test_a_skill_switched_off_cannot_be_fetched_anyway(db, chat, user_id, skill):
+    """Without this the narrowing is advisory: a model can name a skill it was
+    never shown -- from an earlier turn, from a note -- and the runner would
+    happily fetch it. Same rule as "what may be run is what was offered"."""
+    import asyncio
+
+    user = db.get(User, user_id)
+    chat.scope_json = {"skills": {"weekly-report": False}}
+    db.commit()
+
+    context = tools_service.context_for(db, user, chat)
+    outcome = asyncio.run(
+        tools_service.run_tool(context, "skill_get", '{"name": "weekly-report"}')
+    )
+    assert outcome.event["status"] == "error"
+
+
+def test_the_last_skill_switched_off_withdraws_skill_get(db, chat, user_id, skill):
+    user = db.get(User, user_id)
+    assert "skill_get" in _names(db, chat, user)
+
+    chat.scope_json = {"skills": {"weekly-report": False}}
+    db.commit()
+
+    offered = _names(db, chat, user)
+    assert "skill_get" not in offered
+    assert "skill_create" in offered, "writing the first one is still possible"
+
+
+# --- The zero-skills asymmetry --------------------------------------------------------
+def test_with_no_skills_nothing_tells_the_model_to_read_one(db, chat, user_id):
+    """The complaint this fixes. `tool.skills` was gated on the family alone, so
+    a person with no skills got "read the full instructions with skill_get"
+    above a list that was not there -- and got skill_get in the tools array, so
+    the model spent a round finding out."""
+    from lembas.services import harness
+
+    user = db.get(User, user_id)
+    offered = tools_service.resolve_tools(db, chat, user).schemas
+    text = harness.compose(db, user, offered, chat)
+
+    assert "skill_get" not in _names(db, chat, user)
+    assert "skill_get" not in text
+    assert "Skills available" not in text
+    # The half that is most useful with none: you can save the first one.
+    assert "save it with skill_create" in text
+
+
+def test_with_a_skill_the_reading_guidance_comes_back(db, chat, user_id, skill):
+    from lembas.services import harness
+
+    user = db.get(User, user_id)
+    offered = tools_service.resolve_tools(db, chat, user).schemas
+    text = harness.compose(db, user, offered, chat)
+
+    assert "skill_get" in text
+    assert "weekly-report" in text
+    assert "save it with skill_create" in text
+
+
+# --- The tool list --------------------------------------------------------------------
+def test_the_model_is_told_what_it_actually_has(db, chat, user_id):
+    """`tool_names` was resolved and documented with no fragment reading it. A
+    model that has to discover its own list by calling something and being told
+    it does not exist spends a round finding out -- and with one round, that is
+    the whole reply."""
+    from lembas.services import harness
+
+    user = db.get(User, user_id)
+    offered = tools_service.resolve_tools(db, chat, user).schemas
+    text = harness.compose(db, user, offered, chat)
+
+    assert "The tools you have on this request are:" in text
+    for name in tools_service.resolve_tools(db, chat, user).by_name:
+        assert name in text
+
+
+def test_a_family_switched_off_disappears_from_the_list_too(db, chat, user_id):
+    from lembas.services import harness
+
+    settings_store.update(db, {"enabled": True}, key=settings_store.SEARCH)
+    user = db.get(User, user_id)
+    chat.scope_json = {"families": {"web_search": False}}
+    db.commit()
+
+    offered = tools_service.resolve_tools(db, chat, user).schemas
+    text = harness.compose(db, user, offered, chat)
+
+    assert "web_search" not in text
+
+
+def test_no_tools_means_no_list(db, chat, user_id):
+    from lembas.services import harness
+
+    text = harness.compose(db, db.get(User, user_id), [])
+    assert "The tools you have on this request" not in text
+
+
+# --- The control that writes ------------------------------------------------------------
+def test_the_verb_is_on_every_checkbox(client: TestClient, db, chat, registered):
+    """The element carrying `name` has to be the element carrying the request.
+    Two selects lost an entire release to getting this wrong -- their verb was
+    on a form the event never reached, and the tests passed throughout because
+    they asserted the markup rather than the property.
+
+    `conftest.control_named` is the helper for this and wants exactly one match;
+    there is one checkbox per family here, so the same check is made over all of
+    them, which is the stronger claim anyway.
+    """
+    from html.parser import HTMLParser
+
+    settings_store.update(db, {"enabled": True}, key=settings_store.SEARCH)
+    html = client.get(f"/chat/{chat.id}").text
+
+    found: list[dict[str, str]] = []
+
+    class Finder(HTMLParser):
+        def handle_starttag(self, tag, attrs):
+            got = {key: (value or "") for key, value in attrs}
+            if got.get("name") == "on":
+                found.append(got)
+
+    Finder().feed(html)
+
+    assert found, "the scope menu rendered no switches"
+    for box in found:
+        assert box.get("hx-post") == f"/api/chats/{chat.id}/scope"
+        assert "kind" in box.get("hx-vals", ""), "and says which thing it is"
diff --git a/tests/test_commands_js.py b/tests/test_commands_js.py
new file mode 100644
index 0000000..b9ea00a
--- /dev/null
+++ b/tests/test_commands_js.py
@@ -0,0 +1,60 @@
+"""The keyboard, checked without a runtime.
+
+There is no JavaScript test runner here and hard rule 1 keeps Node out of the
+project, so the behaviour is driven by hand under a DOM stub before committing.
+What can be pinned in the suite is the invariant the file states about itself:
+`/help` reads `SHORTCUTS`, so a shortcut that is not in that list is a shortcut
+nobody can discover. That is the direction this actually rots -- a key gets
+added to the handler and the sheet is forgotten.
+"""
+
+from __future__ import annotations
+
+import re
+from pathlib import Path
+
+import lembas
+
+SOURCE = (
+    Path(lembas.__file__).parent / "web/static/js/commands.js"
+).read_text(encoding="utf-8")
+
+# The declared list, up to where the command table starts.
+SHORTCUTS = SOURCE[SOURCE.index("var SHORTCUTS") : SOURCE.index("/* --- The table")]
+
+
+def test_every_letter_key_the_handlers_match_is_described():
+    letters = {match[-1] for match in re.findall(r'event\.code === "Key([A-Z])"', SOURCE)}
+    assert letters, "no letter shortcuts found at all, which means the regex is wrong"
+
+    missing = [letter for letter in sorted(letters) if f"+ {letter}" not in SHORTCUTS]
+    assert not missing, f"not in /help: {missing}"
+
+
+def test_the_three_new_ones_are_there():
+    """Named rather than only counted, because the point of them is being
+    findable: Enter already sends *inside the box*, and dictation and read-aloud
+    were click-only."""
+    assert "Ctrl/⌘ + Enter" in SHORTCUTS
+    assert "Alt + M" in SHORTCUTS
+    assert "Alt + R" in SHORTCUTS
+
+
+def test_dictation_is_not_bound_to_alt_d():
+    """Alt+D is the address bar in Chrome and Firefox on Windows and Linux. A
+    shortcut the browser wins is a shortcut that looks broken."""
+    assert 'event.code === "KeyD"' not in SOURCE
+
+
+def test_the_shortcuts_are_matched_on_the_physical_key():
+    """The file's own stated rule: `event.code`, so a Dvorak or Slovak layout
+    gets the same shortcuts rather than whichever letters sit there."""
+    assert "event.key ===" not in SOURCE
+
+
+def test_send_from_anywhere_never_means_stop():
+    """Send and Stop are the same element. Ctrl+Enter reaching it while it is
+    Stop would abandon a reply on a key people press to send -- and Esc already
+    stops."""
+    window = SOURCE[SOURCE.index('event.code === "Enter"') :][:600]
+    assert 'composerAction === "send"' in window
diff --git a/tests/test_effort.py b/tests/test_effort.py
index 7c951b7..44d58e6 100644
--- a/tests/test_effort.py
+++ b/tests/test_effort.py
@@ -230,3 +230,139 @@ def test_a_nonsense_effort_at_the_start_falls_back(client: TestClient, db, regis
     )
 
     assert db.scalars(select(Chat)).one().params_json["reasoning_effort"] == "high"
+
+
+# --- What the picker says is what is sent ---------------------------------------
+def test_the_resolver_is_what_the_request_carries(client: TestClient, db, registered):
+    """One resolver, so the control and the request cannot disagree. That
+    disagreement is the whole reason the picker said "default": it named no
+    level, and was true of nothing in particular."""
+    chat = _chat(db, "high")
+
+    assert chat_service.resolved_effort(chat) == "high"
+    assert chat_service.build_request(db, chat)["reasoning_effort"] == "high"
+
+
+def test_a_cleared_effort_is_not_resurrected_by_the_models_default(
+    client: TestClient, db, registered
+):
+    """What the no-fallback decision buys. If `build_request` fell back to the
+    model, `update_chat` storing None for a cleared effort would be undone
+    underneath it and the off option would silently do nothing."""
+    model = _model(db)
+    model.params_json = {"reasoning_effort": "high"}
+    user = db.scalars(select(User)).first()
+    chat = Chat(
+        user_id=user.id,
+        model_id=model.model_id,
+        connection_id=model.connection_id,
+        params_json={"reasoning_effort": None},
+    )
+    db.add(chat)
+    db.commit()
+
+    assert chat_service.resolved_effort(chat) == ""
+    body = chat_service.build_request(db, chat)
+    assert "reasoning_effort" not in body
+    assert "chat_template_kwargs" not in body
+
+
+def test_choosing_off_before_the_chat_exists_sends_nothing(
+    client: TestClient, db, registered
+):
+    """The one that would otherwise ship broken. `start_chat` declares
+    `Form("")`, so an absent field and an empty one are the same thing there --
+    with `value=""` on the off option the reader picks off, the value falls out
+    of EFFORTS, and the model's default seeded onto the row stays. They get
+    "high"."""
+    model = _model(db)
+    model.params_json = {"reasoning_effort": "high"}
+    db.commit()
+
+    client.post(
+        "/api/chats/start",
+        data={"content": "hello", "model_id": "m", "reasoning_effort": "off"},
+    )
+    chat = db.scalars(select(Chat)).first()
+
+    assert not (chat.params_json or {}).get("reasoning_effort")
+    assert "reasoning_effort" not in chat_service.build_request(db, chat)
+
+
+def test_patching_off_clears_it(client: TestClient, db, registered):
+    chat = _chat(db, "high")
+    client.patch(f"/api/chats/{chat.id}", data={"reasoning_effort": "off"})
+
+    db.expire_all()
+    assert chat_service.resolved_effort(db.get(Chat, chat.id)) == ""
+
+
+def test_switching_model_seeds_an_effort_that_was_never_chosen(
+    client: TestClient, db, registered
+):
+    """So "what the picker shows is what is sent" stays true after a switch."""
+    chat = _chat(db)
+    second = Model(
+        connection_id=chat.connection_id,
+        model_id="m2",
+        capabilities_json={"reasoning": True},
+        params_json={"reasoning_effort": "medium"},
+    )
+    db.add(second)
+    db.commit()
+
+    client.patch(f"/api/chats/{chat.id}", data={"model_id": "m2"})
+
+    db.expire_all()
+    assert chat_service.resolved_effort(db.get(Chat, chat.id)) == "medium"
+
+
+def test_switching_model_does_not_overwrite_a_chosen_effort(
+    client: TestClient, db, registered
+):
+    chat = _chat(db, "low")
+    second = Model(
+        connection_id=chat.connection_id,
+        model_id="m2",
+        capabilities_json={"reasoning": True},
+        params_json={"reasoning_effort": "high"},
+    )
+    db.add(second)
+    db.commit()
+
+    client.patch(f"/api/chats/{chat.id}", data={"model_id": "m2"})
+
+    db.expire_all()
+    assert chat_service.resolved_effort(db.get(Chat, chat.id)) == "low"
+
+
+def test_switching_model_does_not_resurrect_a_cleared_effort(
+    client: TestClient, db, registered
+):
+    """`None` means somebody cleared it deliberately. Only an ABSENT key is
+    seeded, or "off" would silently undo itself on the next model change."""
+    chat = _chat(db, "high")
+    client.patch(f"/api/chats/{chat.id}", data={"reasoning_effort": "off"})
+    second = Model(
+        connection_id=chat.connection_id,
+        model_id="m2",
+        capabilities_json={"reasoning": True},
+        params_json={"reasoning_effort": "high"},
+    )
+    db.add(second)
+    db.commit()
+
+    client.patch(f"/api/chats/{chat.id}", data={"model_id": "m2"})
+
+    db.expire_all()
+    assert chat_service.resolved_effort(db.get(Chat, chat.id)) == ""
+
+
+def test_the_picker_never_says_default(client: TestClient, db, registered):
+    """The one markup assertion. It named no level and was true of nothing."""
+    chat = _chat(db, "medium")
+    html = client.get(f"/chat/{chat.id}").text
+
+    assert "Effort: default" not in html
+    assert "Effort: off" in html
+    assert '<option value="medium" selected>' in html.replace("\n", "").replace("  ", "")
diff --git a/tests/test_memory.py b/tests/test_memory.py
new file mode 100644
index 0000000..54f6ecc
--- /dev/null
+++ b/tests/test_memory.py
@@ -0,0 +1,116 @@
+"""Memory: the two ways it used to lose somebody's facts quietly.
+
+`memory_forget` was a case-insensitive substring FIRST-match delete with nothing
+warning about it, so a short fragment removed whichever memory happened to be
+older -- and a wrong deletion here is not something anybody finds out about.
+`memory_add` had no defence against the same fact being stored four times in
+slightly different words, which costs the window forever *and* makes every
+forget after it ambiguous.
+
+Both are asserted on the rows, not on the wording.
+"""
+
+from __future__ import annotations
+
+import pytest
+from sqlalchemy import func, select
+
+from lembas.db.models import Memory, User
+from lembas.security.passwords import hash_password
+from lembas.services import tools as tools_service
+from lembas.services.library import memories as memories_service
+
+
+@pytest.fixture
+def owner(db):
+    user = User(name="Frodo", email="f@shire.test", password_hash=hash_password("x"))
+    db.add(user)
+    db.commit()
+    return user
+
+
+def _count(db, owner) -> int:
+    return db.scalar(
+        select(func.count()).select_from(Memory).where(Memory.owner_id == owner.id)
+    )
+
+
+def _forget(owner, text: str):
+    import asyncio
+
+    context = tools_service.ToolContext(owner_id=owner.id)
+    return asyncio.run(tools_service.run_tool(context, "memory_forget", f'{{"content": "{text}"}}'))
+
+
+# --- Forgetting ----------------------------------------------------------------
+def test_an_ambiguous_forget_removes_nothing(db, owner):
+    """Two memories about coffee; "coffee" names neither of them."""
+    memories_service.add(db, owner=owner, content="Drinks coffee black.")
+    memories_service.add(db, owner=owner, content="Allergic to coffee.")
+
+    outcome = _forget(owner, "coffee")
+
+    assert _count(db, owner) == 2
+    assert outcome.event["status"] == "error"
+    assert "Drinks coffee black." in outcome.content
+    assert "Allergic to coffee." in outcome.content
+
+
+def test_quoting_a_memory_in_full_removes_that_one(db, owner):
+    """Exact-first is what makes this work. "Drinks coffee." is a substring of
+    "Drinks coffee. Never tea." too, so a substring-only match would call the
+    unambiguous case ambiguous and refuse to do anything at all."""
+    short = memories_service.add(db, owner=owner, content="Drinks coffee.")
+    long = memories_service.add(db, owner=owner, content="Drinks coffee. Never tea.")
+    short_id, long_id = short.id, long.id
+
+    _forget(owner, "Drinks coffee.")
+
+    db.expire_all()
+    assert db.get(Memory, short_id) is None
+    assert db.get(Memory, long_id) is not None
+
+
+def test_forgetting_something_that_is_not_there_says_so(db, owner):
+    memories_service.add(db, owner=owner, content="Drinks coffee black.")
+    outcome = _forget(owner, "tea")
+    assert _count(db, owner) == 1
+    assert outcome.event["status"] == "error"
+
+
+def test_an_unambiguous_fragment_still_works(db, owner):
+    """Quoting in full is what the description asks for, but a fragment that
+    genuinely names one memory should not be made to fail."""
+    memories_service.add(db, owner=owner, content="Drinks coffee black.")
+    memories_service.add(db, owner=owner, content="Lives in Bree.")
+
+    _forget(owner, "Bree")
+
+    db.expire_all()
+    assert _count(db, owner) == 1
+
+
+# --- Adding --------------------------------------------------------------------
+def test_an_exact_duplicate_creates_nothing(db, owner):
+    first = memories_service.add(db, owner=owner, content="Prefers metric units.")
+    again = memories_service.add(db, owner=owner, content="  Prefers   metric units.  ")
+
+    assert _count(db, owner) == 1
+    assert again.id == first.id
+
+
+def test_the_limit_refuses_and_does_not_tell_the_model_to_guess(db, owner, monkeypatch):
+    """Past MAX_TOTAL_CHARS the injected block is truncated, so the model is not
+    shown every memory. Telling it to remove one to make room asks it to choose
+    blind -- and the forget path above is exactly where blind guessing bites."""
+    monkeypatch.setattr(memories_service, "MAX_RECORDS", 3)
+    for index in range(3):
+        memories_service.add(db, owner=owner, content=f"Fact {index}")
+
+    with pytest.raises(ValueError) as caught:
+        memories_service.add(db, owner=owner, content="One too many")
+
+    assert _count(db, owner) == 3
+    message = str(caught.value)
+    assert "note instead" in message
+    assert "Remove one first" not in message