diff --git a/docs/swarm/inference.md b/docs/swarm/inference.md
index 1b71df78..7c75b76e 100644
--- a/docs/swarm/inference.md
+++ b/docs/swarm/inference.md
@@ -26,7 +26,8 @@ swarmctl agent inference clear iris
   running on, each with where it comes from.
 - `clear` removes every field; the agent goes back to its own values.
 
-The full flag reference is [`swarmctl-cli.md`](../tools/swarmctl-cli.md).
+The full flag reference is [`swarmctl-cli.md`](../tools/swarmctl-cli.md). The
+swarm UI's agents page edits the same settings; see [UI](ui.md).
 
 ## What an agent runs on
 
diff --git a/docs/swarm/ui.md b/docs/swarm/ui.md
index 87fd4865..7924dbe3 100644
--- a/docs/swarm/ui.md
+++ b/docs/swarm/ui.md
@@ -7,15 +7,15 @@ domain, covers host-level detail for one hive.
 
 ## What it shows
 
-| route                                          | what                                                                                                |
-| ---------------------------------------------- | --------------------------------------------------------------------------------------------------- |
-| `/`                                            | the hive directory, each hive with its last reported status                                         |
-| `/agents`                                      | every agent: status, config PR, wanted state; create agents, link forge, matrix and GitHub accounts |
-| `/agents/<name>/terminal`                      | one agent's live terminal                                                                           |
-| `/agents/<name>/subagents/<subagent>/terminal` | one of that agent's subagents' live terminal                                                        |
-| `/jobs`                                        | the controller's job graph — where agent creation and credential mints show progress                |
-| `/schedules`                                   | the scheduled prompts: add, edit, pause, resume and remove                                          |
-| `/issues`                                      | a cross-repo issue report                                                                           |
+| route                                          | what                                                                                                                    |
+| ---------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------- |
+| `/`                                            | the hive directory, each hive with its last reported status                                                             |
+| `/agents`                                      | every agent: status, config PR, wanted state, inference settings; create agents, link forge, matrix and GitHub accounts |
+| `/agents/<name>/terminal`                      | one agent's live terminal                                                                                               |
+| `/agents/<name>/subagents/<subagent>/terminal` | one of that agent's subagents' live terminal                                                                            |
+| `/jobs`                                        | the controller's job graph — where agent creation and credential mints show progress                                    |
+| `/schedules`                                   | the scheduled prompts: add, edit, pause, resume and remove                                                              |
+| `/issues`                                      | a cross-repo issue report                                                                                               |
 
 Everything it shows comes from [`swarm-controller`](../../swarm-controller/README.md).
 An agent created here or with `swarmctl agent create` starts `paused`; set it
@@ -102,6 +102,19 @@ store identity, or no queue address, publishes no subagent terminals.
 
 </details>
 
+### Inference settings
+
+The agent's detail panel shows its model and effort under **inference**, each
+with where it comes from: the swarm, its agent.nix, its own pick, or the
+default. Below them is the subagent model list the swarm sets, or "its own"
+when it sets none. **edit** opens a dialog with the three fields, filled with
+what the swarm stores; saving does a `PUT /api/agents/{agent}/inference` of
+the whole value, and a field left empty is left out, so that field stays the
+agent's own. **clear the swarm's setting** sends the `DELETE`. The values
+shown come from `GET /api/agents/{agent}/inference`; before the agent's first
+report reaches the controller, the panel shows the swarm's stored values only.
+The settings themselves are described in [inference](inference.md).
+
 ### Linking external accounts
 
 Each agent on `/agents` opens three dialogs that write a credential for it
diff --git a/frontend/packages/swarm-ui/src/pages/agents/AgentInference.css b/frontend/packages/swarm-ui/src/pages/agents/AgentInference.css
new file mode 100644
index 00000000..f7f0a2b7
--- /dev/null
+++ b/frontend/packages/swarm-ui/src/pages/agents/AgentInference.css
@@ -0,0 +1,40 @@
+/* <AgentInference> — one setting per line: badge, then where it comes from. */
+.ui-agent-inference {
+  display: flex;
+  flex-direction: column;
+  align-items: flex-start;
+  gap: 0.3em;
+}
+.ui-agent-inference-list {
+  list-style: none;
+  margin: 0;
+  padding: 0;
+  display: grid;
+  gap: 0.3em;
+}
+.ui-agent-inference-list li {
+  display: flex;
+  align-items: center;
+  gap: 0.5em;
+  flex-wrap: wrap;
+}
+.ui-agent-inference-source,
+.ui-agent-inference-muted {
+  color: var(--muted);
+}
+.ui-agent-inference-form {
+  display: flex;
+  flex-direction: column;
+  align-items: flex-start;
+  gap: 0.75em;
+  margin-top: 1em;
+}
+.ui-agent-inference-problem {
+  margin: 0;
+  color: var(--red);
+}
+.ui-agent-inference-actions {
+  display: flex;
+  align-items: center;
+  gap: 0.75em;
+}
diff --git a/frontend/packages/swarm-ui/src/pages/agents/AgentInference.tsx b/frontend/packages/swarm-ui/src/pages/agents/AgentInference.tsx
new file mode 100644
index 00000000..f23936d3
--- /dev/null
+++ b/frontend/packages/swarm-ui/src/pages/agents/AgentInference.tsx
@@ -0,0 +1,301 @@
+// <AgentInference> — one agent's inference settings on the detail panel: the
+// model and effort it runs on now, with where each came from, and an editor
+// for the value the swarm sets.
+//
+// Reads `GET /api/agents/{name}/inference`, which answers
+// `{ configured, effective }`: `configured` is the swarm's stored value (null
+// when none), `effective` what the agent reported running on (null until its
+// first report reaches the controller). The editor PUTs the whole value and
+// the clear action DELETEs it; a cleared field puts the agent back on its own
+// value, which is why an empty field is left out of the body rather than sent.
+//
+// Its state belongs to one agent: callers key it by agent name, so switching
+// agents remounts it instead of showing the previous agent's settings.
+import { useEffect, useState } from "preact/hooks";
+import { ApiErrorPanel } from "@hive/shared/api-error-panel.js";
+import { readApiError, type ProblemDetails } from "@hive/shared/api-error.js";
+import { Badge } from "@hive/shared/badge.js";
+import { Dialog } from "../../ui/dialog/Dialog.js";
+import { Panel } from "../../ui/panel/Panel.js";
+import { SelectField } from "../../ui/select-field/SelectField.js";
+import { TextField } from "../../ui/text-field/TextField.js";
+import { Button } from "../../ui/button/Button.js";
+import "./AgentInference.css";
+
+type Source = "swarm" | "agent_nix" | "local_file" | "default";
+
+// Mirrors the swarm's `InferenceSettings`; every field is optional.
+interface Settings {
+  model?: string;
+  effort?: string;
+  subagent_models?: string[];
+}
+
+// Mirrors `EffectiveInference`.
+interface Effective {
+  model: string;
+  effort: string;
+  model_source: Source;
+  effort_source: Source;
+}
+
+interface View {
+  configured: Settings | null;
+  effective: Effective | null;
+}
+
+// The values the swarm accepts for `effort`.
+const EFFORTS = ["low", "medium", "high", "xhigh", "max"];
+const EFFORT_OPTIONS = [
+  { value: "", label: "the agent's own" },
+  ...EFFORTS.map((e) => ({ value: e, label: e })),
+];
+
+const SOURCE_LABEL: Record<Source, string> = {
+  swarm: "swarm",
+  agent_nix: "agent.nix",
+  local_file: "its own pick",
+  default: "default",
+};
+
+// The same checks the swarm makes on a model name, so an obviously bad one
+// is refused before the round trip; the swarm stays the real gate.
+function modelNameProblem(name: string): string | null {
+  if (/\s/.test(name)) return "a model name has no whitespace";
+  if (name.startsWith("-")) return "a model name does not start with -";
+  return null;
+}
+
+// Subagent models are typed as one list, split on commas and whitespace.
+function parseModels(text: string): string[] {
+  return text.split(/[\s,]+/).filter((m) => m !== "");
+}
+
+function inferenceUrl(agent: string): string {
+  return `/api/agents/${encodeURIComponent(agent)}/inference`;
+}
+
+export function AgentInference({ agent }: { agent: string }) {
+  const [view, setView] = useState<View | null>(null);
+  const [error, setError] = useState<ProblemDetails | null>(null);
+  // Bumped after a save or a clear, so the settings are fetched again.
+  const [reload, setReload] = useState(0);
+  const [editing, setEditing] = useState(false);
+
+  useEffect(() => {
+    let cancelled = false;
+    (async () => {
+      const r = await fetch(inferenceUrl(agent));
+      if (!r.ok) {
+        if (!cancelled) setError(await readApiError(r));
+        return;
+      }
+      const body = (await r.json()) as Partial<View>;
+      if (cancelled) return;
+      setView({
+        configured: body.configured ?? null,
+        effective: body.effective ?? null,
+      });
+      setError(null);
+    })().catch((e: unknown) => {
+      if (!cancelled) setError({ detail: String(e) });
+    });
+    return () => {
+      cancelled = true;
+    };
+  }, [agent, reload]);
+
+  if (error) {
+    return (
+      <Badge
+        tone="negative"
+        value="inference unavailable"
+        title={error.detail ?? "reading the inference settings failed"}
+      />
+    );
+  }
+  if (view === null) return <span class="ui-agent-inference-muted">…</span>;
+
+  const { configured, effective } = view;
+  const swarmModels = configured?.subagent_models ?? [];
+  return (
+    <div class="ui-agent-inference">
+      <ul class="ui-agent-inference-list">
+        <li>
+          {effective ? (
+            <>
+              <Badge label="model" value={effective.model} />
+              <span class="ui-agent-inference-source">
+                {SOURCE_LABEL[effective.model_source]}
+              </span>
+            </>
+          ) : (
+            <Badge
+              label="model"
+              value={configured?.model ?? "its own"}
+              title="the agent has not reported what it runs on yet"
+            />
+          )}
+        </li>
+        <li>
+          {effective ? (
+            <>
+              <Badge label="effort" value={effective.effort} />
+              <span class="ui-agent-inference-source">
+                {SOURCE_LABEL[effective.effort_source]}
+              </span>
+            </>
+          ) : (
+            <Badge
+              label="effort"
+              value={configured?.effort ?? "its own"}
+              title="the agent has not reported what it runs on yet"
+            />
+          )}
+        </li>
+        <li>
+          <Badge
+            label="subagent models"
+            value={swarmModels.length > 0 ? swarmModels.join(", ") : "its own"}
+          />
+        </li>
+      </ul>
+      <Badge
+        variant="quiet"
+        value="edit"
+        title={`set the swarm's model, effort and subagent models for ${agent}`}
+        onClick={() => setEditing(true)}
+      />
+      <Dialog
+        open={editing}
+        onClose={() => setEditing(false)}
+        label="edit inference settings"
+        plain
+      >
+        {/* Remounted per open, so a cancelled edit leaves nothing behind. */}
+        {editing ? (
+          <InferenceForm
+            agent={agent}
+            configured={configured}
+            onClose={() => setEditing(false)}
+            onSaved={() => {
+              setEditing(false);
+              setReload((n) => n + 1);
+            }}
+          />
+        ) : null}
+      </Dialog>
+    </div>
+  );
+}
+
+function InferenceForm({
+  agent,
+  configured,
+  onClose,
+  onSaved,
+}: {
+  agent: string;
+  configured: Settings | null;
+  onClose: () => void;
+  onSaved: () => void;
+}) {
+  const [model, setModel] = useState(configured?.model ?? "");
+  const [effort, setEffort] = useState(configured?.effort ?? "");
+  const [subagents, setSubagents] = useState(
+    (configured?.subagent_models ?? []).join(", "),
+  );
+  const [busy, setBusy] = useState(false);
+  const [problem, setProblem] = useState<ProblemDetails | null>(null);
+
+  const subagentList = parseModels(subagents);
+  const modelProblem =
+    modelNameProblem(model.trim()) ??
+    subagentList.map(modelNameProblem).find((p) => p !== null) ??
+    null;
+  const empty =
+    model.trim() === "" && effort === "" && subagentList.length === 0;
+
+  async function send(init: RequestInit) {
+    setBusy(true);
+    try {
+      const r = await fetch(inferenceUrl(agent), init);
+      if (!r.ok) {
+        setProblem(await readApiError(r));
+        return;
+      }
+      onSaved();
+    } catch (e: unknown) {
+      setProblem({ detail: String(e) });
+    } finally {
+      setBusy(false);
+    }
+  }
+
+  function save(e: Event) {
+    e.preventDefault();
+    const body: Settings = {};
+    if (model.trim() !== "") body.model = model.trim();
+    if (effort !== "") body.effort = effort;
+    if (subagentList.length > 0) body.subagent_models = subagentList;
+    void send({
+      method: "PUT",
+      headers: { "content-type": "application/json" },
+      body: JSON.stringify(body),
+    });
+  }
+
+  return (
+    <Panel title={`inference — ${agent}`} icon="🧠" onClose={onClose}>
+      <p>
+        Sets what the swarm makes {agent} run on. A field left empty stays the
+        agent's own value. The agent picks a change up within seconds; a turn
+        already running finishes on what it started with.
+      </p>
+      <form class="ui-agent-inference-form" onSubmit={save}>
+        <TextField
+          id="inference-model"
+          label="model"
+          value={model}
+          placeholder="e.g. opus"
+          onInput={setModel}
+        />
+        <SelectField
+          id="inference-effort"
+          label="effort"
+          value={effort}
+          options={EFFORT_OPTIONS}
+          onChange={setEffort}
+        />
+        <TextField
+          id="inference-subagent-models"
+          label="subagent models"
+          value={subagents}
+          placeholder="e.g. haiku, sonnet"
+          onInput={setSubagents}
+        />
+        {modelProblem ? (
+          <p class="ui-agent-inference-problem">{modelProblem}</p>
+        ) : null}
+        {problem ? (
+          <ApiErrorPanel context="saving failed" problem={problem} />
+        ) : null}
+        <div class="ui-agent-inference-actions">
+          <Button
+            variant="primary"
+            type="submit"
+            disabled={busy || empty || modelProblem !== null}
+          >
+            {busy ? "saving…" : "save"}
+          </Button>
+          <Button
+            disabled={busy || configured === null}
+            onClick={() => void send({ method: "DELETE" })}
+          >
+            clear the swarm's setting
+          </Button>
+        </div>
+      </form>
+    </Panel>
+  );
+}
diff --git a/frontend/packages/swarm-ui/src/pages/agents/AgentsPage.tsx b/frontend/packages/swarm-ui/src/pages/agents/AgentsPage.tsx
index 28faff3f..3328cebd 100644
--- a/frontend/packages/swarm-ui/src/pages/agents/AgentsPage.tsx
+++ b/frontend/packages/swarm-ui/src/pages/agents/AgentsPage.tsx
@@ -34,6 +34,7 @@ import { AgentCard } from "./AgentCard.js";
 import { AgentTermPreview } from "./AgentTermPreview.js";
 import { SubagentTerms } from "./SubagentTerms.js";
 import { FRESHNESS, type AgentRow } from "./AgentTypes.js";
+import { AgentInference } from "./AgentInference.js";
 import { LinkedAccounts } from "./LinkedAccounts.js";
 import { LinkAccountMenu } from "./LinkAccountMenu.js";
 import { Button } from "../../ui/button/Button.js";
@@ -588,6 +589,13 @@ export function AgentsPage() {
                       "—"
                     )}
                   </dd>
+                  <dt>inference</dt>
+                  <dd>
+                    <AgentInference
+                      key={detailTarget.name}
+                      agent={detailTarget.name}
+                    />
+                  </dd>
                   <dt>accounts</dt>
                   <dd>
                     {detailTarget.hive ? (