diff --git a/README.md b/README.md
index 76093d1..ff4a451 100644
--- a/README.md
+++ b/README.md
@@ -1434,7 +1434,7 @@ When the embedded query (`card.dataset_query`, `transform.source.query` for `sou
 
 Pass `--skip-validate` to bypass the pre-flight on any of `card create`, `card update`, `transform create`, `transform update`, `measure create`, `measure update`, `segment create`, or `segment update` — the body is sent as-is and the server is the authority. Same escape hatch as on `mb query`; use only when the bundled schema disagrees with what the server actually accepts.
 
-Agent discovery path: `mb <command> --help --json` lists a command's args and output schema; the description for `card create`/`update`, `transform create`/`update`, `measure create`/`update`, and `segment create`/`update` references `mb query --print-schema` so an agent can fetch the validating schema directly.
+Agent discovery path: `mb <command> --help --json` lists a command's args, JSON-body input schema, and output schema; the description for `card create`/`update`, `transform create`/`update`, `measure create`/`update`, and `segment create`/`update` references `mb query --print-schema` so an agent can fetch the validating schema directly.
 
 The bundled query schema is synced from a pinned `@metabase/representations` release via `bun run sync:representations`; CI guards against drift.
 
@@ -1566,12 +1566,13 @@ The former `METABASE_`-prefixed names (`METABASE_URL`, `METABASE_API_KEY`, `META
 
 Every node of the command tree answers `--help --json` with machine-readable help, mirroring what text help shows at that level:
 
-- A leaf command emits its full entry — name, description, `details`, examples, citty args with types/defaults/enums, `capabilities` (min server version / token feature), and the output Zod schema rendered as JSON Schema.
+- A leaf command emits its full entry — name, description, `details`, examples, citty args with types/defaults/enums, `capabilities` (min server version / token feature), and the input and output Zod schemas rendered as JSON Schema (`inputSchema` is the exact validator `readBody` enforces on the JSON body, `null` for commands that take none).
 - A command group (and the root) emits a flat `{ commands: [{ command, description }] }` index of every leaf in its subtree, with full-path names.
 
 ```sh
 mb --help --json | jq -r '.commands[].command'    # every command
 mb card query --help --json | jq .outputSchema    # one command's output schema
+mb card create --help --json | jq .inputSchema    # the JSON-body contract it validates
 ```
 
 The entry and index schemas (`CommandHelpEntry`, `CommandHelpIndex`) are exported from `src/runtime/command-help.ts`.
diff --git a/skill-data/core/SKILL.md b/skill-data/core/SKILL.md
index 018eaaf..dbda329 100644
--- a/skill-data/core/SKILL.md
+++ b/skill-data/core/SKILL.md
@@ -105,11 +105,12 @@ Cheapest source that answers the question wins:
 
 - What groups/verbs exist? → `mb --help`, then `mb <group> --help`. Add `--json` for a machine-readable `{command, description}` index (`mb --help --json` lists every command).
 - What flags does a command take? → `mb <command> --help` — flags with enums and defaults, examples, ~1 KB.
-- Output JSON Schema before parsing, machine-readable arg types, min server version? → `mb <command> --help --json` — that command's full entry.
+- Output JSON Schema before parsing, JSON-body input schema before authoring, machine-readable arg types, min server version? → `mb <command> --help --json` — that command's full entry (`inputSchema` is the exact validator the command runs on the body; `null` when it takes none).
 
 ```bash
 mb card query --help                                    # flags, enums, defaults, examples
 mb card list --help --json | jq .outputSchema           # output schema before parsing
+mb card create --help --json | jq .inputSchema          # body schema before authoring
 mb transform --help --json | jq -r '.commands[].command'  # verbs under "transform"
 ```
 
diff --git a/src/commands/card/create.ts b/src/commands/card/create.ts
index bb66d81..2017c08 100644
--- a/src/commands/card/create.ts
+++ b/src/commands/card/create.ts
@@ -30,6 +30,7 @@ export default defineMetabaseCommand({
     ...bodyInputFlags,
     ...skipValidateFlag,
   },
+  inputSchema: CardCreateInput,
   outputSchema: Card,
   examples: [
     "cat card.json | mb card create",
diff --git a/src/commands/card/update.ts b/src/commands/card/update.ts
index e92c037..63882e2 100644
--- a/src/commands/card/update.ts
+++ b/src/commands/card/update.ts
@@ -31,6 +31,7 @@ export default defineMetabaseCommand({
     ...skipValidateFlag,
     id: { type: "positional", description: "Card id", required: true },
   },
+  inputSchema: CardUpdateInput,
   outputSchema: Card,
   examples: [
     "cat patch.json | mb card update 1",
diff --git a/src/commands/collection/create.ts b/src/commands/collection/create.ts
index 0f21d46..fe78701 100644
--- a/src/commands/collection/create.ts
+++ b/src/commands/collection/create.ts
@@ -26,6 +26,7 @@ export default defineMetabaseCommand({
       description: `Collection namespace: ${CollectionNamespace.options.join("|")} (omit for a normal collection)`,
     },
   },
+  inputSchema: CollectionCreateInput,
   outputSchema: Collection,
   examples: [
     "cat collection.json | mb collection create",
diff --git a/src/commands/dashboard/create.ts b/src/commands/dashboard/create.ts
index 12945ff..7e639f7 100644
--- a/src/commands/dashboard/create.ts
+++ b/src/commands/dashboard/create.ts
@@ -30,6 +30,7 @@ export default defineMetabaseCommand({
     ...connectionFlags,
     ...bodyInputFlags,
   },
+  inputSchema: DashboardCreateInput,
   outputSchema: Dashboard,
   examples: [
     "cat dashboard.json | mb dashboard create",
diff --git a/src/commands/dashboard/preflight.ts b/src/commands/dashboard/preflight.ts
index 6e2efa0..d38f8ef 100644
--- a/src/commands/dashboard/preflight.ts
+++ b/src/commands/dashboard/preflight.ts
@@ -19,9 +19,9 @@ interface CardReference {
 type CardCheck = { status: "ok" } | { status: "error"; message: string };
 
 export function collectDashcardCardReferences(
-  dashcards: ReadonlyArray<unknown> | undefined,
+  dashcards: ReadonlyArray<unknown> | null | undefined,
 ): CardReference[] {
-  if (dashcards === undefined) {
+  if (dashcards === undefined || dashcards === null) {
     return [];
   }
   const refs: CardReference[] = [];
@@ -40,7 +40,7 @@ export function collectDashcardCardReferences(
 
 export async function preflightDashcardCardReferences(
   client: Client,
-  dashcards: ReadonlyArray<unknown> | undefined,
+  dashcards: ReadonlyArray<unknown> | null | undefined,
 ): Promise<void> {
   const references = collectDashcardCardReferences(dashcards);
   if (references.length === 0) {
diff --git a/src/commands/dashboard/update-dashcard.ts b/src/commands/dashboard/update-dashcard.ts
index 09dc0f3..c5c822f 100644
--- a/src/commands/dashboard/update-dashcard.ts
+++ b/src/commands/dashboard/update-dashcard.ts
@@ -26,6 +26,7 @@ export default defineMetabaseCommand({
     "dashboard-id": { type: "positional", description: "Dashboard id", required: true },
     "dashcard-id": { type: "positional", description: "Dashcard id", required: true },
   },
+  inputSchema: DashcardPatchInput,
   outputSchema: Dashcard,
   examples: [
     'mb dashboard update-dashcard 1 5 --body \'{"row":2,"col":0}\'',
diff --git a/src/commands/dashboard/update.ts b/src/commands/dashboard/update.ts
index f3f2328..acf370c 100644
--- a/src/commands/dashboard/update.ts
+++ b/src/commands/dashboard/update.ts
@@ -27,6 +27,7 @@ export default defineMetabaseCommand({
     ...bodyInputFlags,
     id: { type: "positional", description: "Dashboard id", required: true },
   },
+  inputSchema: DashboardUpdateInput,
   outputSchema: DashboardDetail,
   examples: [
     "cat patch.json | mb dashboard update 1",
diff --git a/src/commands/document/create.ts b/src/commands/document/create.ts
index 175592a..51a5d1c 100644
--- a/src/commands/document/create.ts
+++ b/src/commands/document/create.ts
@@ -9,6 +9,7 @@ export default defineMetabaseCommand({
   meta: { name: "create", description: "Create a document" },
   capabilities: { minVersion: 58 },
   args: { ...outputFlags, ...profileFlag, ...connectionFlags, ...bodyInputFlags },
+  inputSchema: DocumentCreateInput,
   outputSchema: Document,
   examples: [
     "cat doc.json | mb document create",
diff --git a/src/commands/document/update.ts b/src/commands/document/update.ts
index 1c86a14..df4c12d 100644
--- a/src/commands/document/update.ts
+++ b/src/commands/document/update.ts
@@ -16,6 +16,7 @@ export default defineMetabaseCommand({
     ...bodyInputFlags,
     id: { type: "positional", description: "Document id", required: true },
   },
+  inputSchema: DocumentUpdateInput,
   outputSchema: Document,
   examples: [
     "cat patch.json | mb document update 1",
diff --git a/src/commands/eid.ts b/src/commands/eid.ts
index a675671..1fbe80d 100644
--- a/src/commands/eid.ts
+++ b/src/commands/eid.ts
@@ -38,11 +38,12 @@ export default defineMetabaseCommand({
       description: "Comma-separated EIDs to translate (used with --model)",
     },
   },
+  inputSchema: EidTranslateInput,
   outputSchema: EidTranslateResult,
   examples: [
-    "mb eid --model card abc123XYZ,def456ABC",
+    "mb eid --model card Ss3mHTaWs8T-VLPYEeraG,5oQpn8LO4qXBRZ1Wq3jIp",
     "mb eid --file translate.json",
-    'mb eid --body \'{"entity_ids":{"card":["abc123XYZ"]}}\'',
+    'mb eid --body \'{"entity_ids":{"card":["Ss3mHTaWs8T-VLPYEeraG"]}}\'',
   ],
   async run({ args, ctx, getClient }) {
     const pair = requireBothOrNeither(
diff --git a/src/commands/field/update.ts b/src/commands/field/update.ts
index 4444d14..0004fde 100644
--- a/src/commands/field/update.ts
+++ b/src/commands/field/update.ts
@@ -19,6 +19,7 @@ export default defineMetabaseCommand({
     ...bodyInputFlags,
     id: { type: "positional", description: "Field id", required: true },
   },
+  inputSchema: FieldUpdateInput,
   outputSchema: Field,
   examples: [
     'mb field update 100 --body \'{"description":"customer email"}\'',
diff --git a/src/commands/group.ts b/src/commands/group.ts
index 6ec3484..61cd4d1 100644
--- a/src/commands/group.ts
+++ b/src/commands/group.ts
@@ -26,6 +26,7 @@ export function defineCommandGroup(def: CommandGroupDef): CommandDef {
     examples: [],
     details: null,
     skills: def.skills ?? [],
+    inputSchema: null,
     outputSchema: null,
     capabilities: null,
   });
diff --git a/src/commands/measure/create.ts b/src/commands/measure/create.ts
index fc19ceb..6fbc591 100644
--- a/src/commands/measure/create.ts
+++ b/src/commands/measure/create.ts
@@ -26,6 +26,7 @@ export default defineMetabaseCommand({
     ...bodyInputFlags,
     ...skipValidateFlag,
   },
+  inputSchema: MeasureCreateInput,
   outputSchema: Measure,
   examples: [
     "cat measure.json | mb measure create",
diff --git a/src/commands/measure/update.ts b/src/commands/measure/update.ts
index 21b04c3..b6d94db 100644
--- a/src/commands/measure/update.ts
+++ b/src/commands/measure/update.ts
@@ -28,6 +28,7 @@ export default defineMetabaseCommand({
     ...skipValidateFlag,
     id: { type: "positional", description: "Measure id", required: true },
   },
+  inputSchema: MeasureUpdateInput,
   outputSchema: Measure,
   examples: [
     "cat patch.json | mb measure update 1",
diff --git a/src/commands/query.ts b/src/commands/query.ts
index 3270336..0773af0 100644
--- a/src/commands/query.ts
+++ b/src/commands/query.ts
@@ -17,7 +17,11 @@ import { connectionFlags, outputFlags, profileFlag } from "./flags";
 import { defineMetabaseCommand } from "./runtime";
 import { skipValidateFlag } from "./validate-query";
 
-const QueryBody = z.unknown();
+const QueryBody = z
+  .unknown()
+  .describe(
+    "MBQL 5, legacy MBQL, or native query body — full MBQL 5 schema: mb query --print-schema",
+  );
 
 const QUERY_ENDPOINT = "/api/dataset";
 
@@ -45,6 +49,7 @@ export default defineMetabaseCommand({
     },
     ...skipValidateFlag,
   },
+  inputSchema: QueryBody,
   outputSchema: CardQueryResult,
   examples: [
     "mb query --print-schema",
diff --git a/src/commands/runtime.ts b/src/commands/runtime.ts
index 8d811cf..25bcb2c 100644
--- a/src/commands/runtime.ts
+++ b/src/commands/runtime.ts
@@ -48,6 +48,7 @@ export interface MetabaseCommandDef<A extends ArgsDef> {
   examples?: readonly string[];
   details?: string;
   skills?: readonly SkillPointer[];
+  inputSchema?: ZodType;
   outputSchema?: ZodType;
   capabilities?: Partial<Capabilities> | null;
   run: (context: MetabaseCommandContext<A>) => Promise<void> | void;
@@ -125,6 +126,7 @@ export function defineMetabaseCommand<const A extends ArgsDef>(
     examples: def.examples ?? [],
     details: def.details ? def.details : null,
     skills: def.skills ?? [],
+    inputSchema: def.inputSchema ?? null,
     outputSchema: def.outputSchema ?? null,
     capabilities: required,
   });
diff --git a/src/commands/segment/create.ts b/src/commands/segment/create.ts
index d9bb8eb..b74a14e 100644
--- a/src/commands/segment/create.ts
+++ b/src/commands/segment/create.ts
@@ -26,6 +26,7 @@ export default defineMetabaseCommand({
     ...bodyInputFlags,
     ...skipValidateFlag,
   },
+  inputSchema: SegmentCreateInput,
   outputSchema: Segment,
   examples: [
     "cat segment.json | mb segment create",
diff --git a/src/commands/segment/update.ts b/src/commands/segment/update.ts
index 546d4aa..6367872 100644
--- a/src/commands/segment/update.ts
+++ b/src/commands/segment/update.ts
@@ -28,6 +28,7 @@ export default defineMetabaseCommand({
     ...skipValidateFlag,
     id: { type: "positional", description: "Segment id", required: true },
   },
+  inputSchema: SegmentUpdateInput,
   outputSchema: Segment,
   examples: [
     "cat patch.json | mb segment update 1",
diff --git a/src/commands/setting/set.ts b/src/commands/setting/set.ts
index fcdd525..f3021e6 100644
--- a/src/commands/setting/set.ts
+++ b/src/commands/setting/set.ts
@@ -8,6 +8,10 @@ import { defineMetabaseCommand } from "../runtime";
 
 import { parseSettingKey, rethrowSettingError } from "./key";
 
+const SettingValueInput = z
+  .unknown()
+  .describe("Any JSON value; the setting's own type constraints are enforced server-side");
+
 export default defineMetabaseCommand({
   meta: { name: "set", description: "Set a setting value (parsed strictly as JSON)" },
   capabilities: { minVersion: 58 },
@@ -19,6 +23,7 @@ export default defineMetabaseCommand({
     key: { type: "positional", description: "Setting key", required: true },
     value: { type: "positional", description: "JSON-encoded value", required: false },
   },
+  inputSchema: SettingValueInput,
   outputSchema: SettingValue,
   examples: [
     `mb setting set remote-sync-branch '"main"'`,
@@ -31,7 +36,7 @@ export default defineMetabaseCommand({
     const key = parseSettingKey(args.key);
     const value = await readBody(
       { file: args.file, positional: args.value, source: `setting ${key} value` },
-      z.unknown(),
+      SettingValueInput,
     );
     const client = await getClient();
     await client
diff --git a/src/commands/setup.ts b/src/commands/setup.ts
index 39dbb6e..2c1da05 100644
--- a/src/commands/setup.ts
+++ b/src/commands/setup.ts
@@ -18,6 +18,7 @@ export default defineMetabaseCommand({
     ...connectionFlags,
     ...bodyInputFlags,
   },
+  inputSchema: SetupInput,
   outputSchema: SetupResult,
   examples: [
     "cat setup.json | mb setup",
diff --git a/src/commands/snippet/create.ts b/src/commands/snippet/create.ts
index e99eeea..b717023 100644
--- a/src/commands/snippet/create.ts
+++ b/src/commands/snippet/create.ts
@@ -14,6 +14,7 @@ export default defineMetabaseCommand({
     ...connectionFlags,
     ...bodyInputFlags,
   },
+  inputSchema: SnippetCreateInput,
   outputSchema: Snippet,
   examples: [
     "cat snippet.json | mb snippet create",
diff --git a/src/commands/snippet/update.ts b/src/commands/snippet/update.ts
index 8e3ac4b..9c3a7ea 100644
--- a/src/commands/snippet/update.ts
+++ b/src/commands/snippet/update.ts
@@ -16,6 +16,7 @@ export default defineMetabaseCommand({
     ...bodyInputFlags,
     id: { type: "positional", description: "Snippet id", required: true },
   },
+  inputSchema: SnippetUpdateInput,
   outputSchema: Snippet,
   examples: [
     "cat patch.json | mb snippet update 1",
diff --git a/src/commands/table/update.ts b/src/commands/table/update.ts
index 932aef5..2182455 100644
--- a/src/commands/table/update.ts
+++ b/src/commands/table/update.ts
@@ -19,6 +19,7 @@ export default defineMetabaseCommand({
     ...bodyInputFlags,
     id: { type: "positional", description: "Table id", required: true },
   },
+  inputSchema: TableUpdateInput,
   outputSchema: Table,
   examples: [
     'mb table update 42 --body \'{"display_name":"Customers"}\'',
diff --git a/src/commands/transform-job/create.ts b/src/commands/transform-job/create.ts
index 32d00ab..4d03120 100644
--- a/src/commands/transform-job/create.ts
+++ b/src/commands/transform-job/create.ts
@@ -13,6 +13,7 @@ export default defineMetabaseCommand({
   meta: { name: "create", description: "Create a transform job" },
   capabilities: { minVersion: 59 },
   args: { ...outputFlags, ...profileFlag, ...connectionFlags, ...bodyInputFlags },
+  inputSchema: TransformJobCreateInput,
   outputSchema: TransformJob,
   examples: [
     "cat job.json | mb transform-job create",
diff --git a/src/commands/transform-job/update.ts b/src/commands/transform-job/update.ts
index bea8dda..ac87a9a 100644
--- a/src/commands/transform-job/update.ts
+++ b/src/commands/transform-job/update.ts
@@ -20,6 +20,7 @@ export default defineMetabaseCommand({
     ...bodyInputFlags,
     id: { type: "positional", description: "Transform job id", required: true },
   },
+  inputSchema: TransformJobUpdateInput,
   outputSchema: TransformJob,
   examples: [
     "cat patch.json | mb transform-job update 1",
diff --git a/src/commands/transform-tag/create.ts b/src/commands/transform-tag/create.ts
index 6204cb1..a13750b 100644
--- a/src/commands/transform-tag/create.ts
+++ b/src/commands/transform-tag/create.ts
@@ -13,6 +13,7 @@ export default defineMetabaseCommand({
   meta: { name: "create", description: "Create a transform tag" },
   capabilities: { minVersion: 59 },
   args: { ...outputFlags, ...profileFlag, ...connectionFlags, ...bodyInputFlags },
+  inputSchema: TransformTagCreateInput,
   outputSchema: TransformTag,
   examples: [
     'mb transform-tag create --body \'{"name":"nightly"}\'',
diff --git a/src/commands/transform-tag/update.ts b/src/commands/transform-tag/update.ts
index 1a0e175..4336832 100644
--- a/src/commands/transform-tag/update.ts
+++ b/src/commands/transform-tag/update.ts
@@ -20,6 +20,7 @@ export default defineMetabaseCommand({
     ...bodyInputFlags,
     id: { type: "positional", description: "Transform tag id", required: true },
   },
+  inputSchema: TransformTagUpdateInput,
   outputSchema: TransformTag,
   examples: [
     'mb transform-tag update 5 --body \'{"name":"renamed"}\'',
diff --git a/src/commands/transform/create.ts b/src/commands/transform/create.ts
index f45ac79..c4cb2fa 100644
--- a/src/commands/transform/create.ts
+++ b/src/commands/transform/create.ts
@@ -28,6 +28,7 @@ export default defineMetabaseCommand({
     ...bodyInputFlags,
     ...skipValidateFlag,
   },
+  inputSchema: TransformCreateInput,
   outputSchema: Transform,
   examples: [
     "cat transform.json | mb transform create",
diff --git a/src/commands/transform/update.ts b/src/commands/transform/update.ts
index e03873c..1949c63 100644
--- a/src/commands/transform/update.ts
+++ b/src/commands/transform/update.ts
@@ -30,6 +30,7 @@ export default defineMetabaseCommand({
     id: { type: "positional", description: "Transform id", required: true },
     ...skipValidateFlag,
   },
+  inputSchema: TransformUpdateInput,
   outputSchema: Transform,
   examples: [
     "cat patch.json | mb transform update 1",
diff --git a/src/domain/card.ts b/src/domain/card.ts
index f6d0c93..8f4ed60 100644
--- a/src/domain/card.ts
+++ b/src/domain/card.ts
@@ -1,5 +1,6 @@
 import { z } from "zod";
 
+import { EmbeddingParams } from "./embedding";
 import { FieldBaseType, FieldSemanticType } from "./field";
 import { Parameter, ParameterMapping } from "./parameter";
 import type { ResourceView } from "./view";
@@ -19,7 +20,8 @@ export const CardDatasetQuery = z
   .refine((value) => "lib/type" in value || "type" in value, {
     message:
       'dataset_query must include "lib/type" (MBQL 5) or "type" (legacy MBQL/native); empty `{}` is rejected',
-  });
+  })
+  .describe("MBQL 5, legacy MBQL, or native query — full MBQL 5 schema: mb query --print-schema");
 export type CardDatasetQuery = z.infer<typeof CardDatasetQuery>;
 
 export const Card = z
@@ -68,43 +70,52 @@ export const cardView: ResourceView<Card> = {
   ],
 };
 
+const CollectionIdOrEntityId = z.union([
+  z.number().int().positive(),
+  z.string().length(21).describe("collection entity_id (21-char NanoID)"),
+]);
+
 export const CardCreateInput = z
   .object({
     name: z.string().min(1),
-    type: CardType.optional(),
+    type: CardType.nullable().optional(),
     dataset_query: CardDatasetQuery,
     display: z.string().min(1),
     visualization_settings: z.record(z.string(), z.unknown()),
     description: z.string().min(1).nullable().optional(),
-    collection_id: z.number().int().positive().nullable().optional(),
+    entity_id: z.string().min(1).nullable().optional(),
+    collection_id: CollectionIdOrEntityId.nullable().optional(),
     collection_position: z.number().int().positive().nullable().optional(),
+    cache_ttl: z.number().int().positive().nullable().optional(),
     dashboard_id: z.number().int().positive().nullable().optional(),
-    parameters: z.array(Parameter).optional(),
-    parameter_mappings: z.array(ParameterMapping).optional(),
+    dashboard_tab_id: z.number().int().positive().nullable().optional(),
+    parameters: z.array(Parameter).nullable().optional(),
+    parameter_mappings: z.array(ParameterMapping).nullable().optional(),
+    result_metadata: z.array(z.unknown()).nullable().optional(),
   })
   .loose();
 export type CardCreateInput = z.infer<typeof CardCreateInput>;
 
 export const CardUpdateInput = z
   .object({
-    name: z.string().min(1).optional(),
-    type: CardType.optional(),
+    name: z.string().min(1).nullable().optional(),
+    type: CardType.nullable().optional(),
     dataset_query: CardDatasetQuery.optional(),
-    display: z.string().min(1).optional(),
-    visualization_settings: z.record(z.string(), z.unknown()).optional(),
+    display: z.string().min(1).nullable().optional(),
+    visualization_settings: z.record(z.string(), z.unknown()).nullable().optional(),
     description: z.string().nullable().optional(),
-    archived: z.boolean().optional(),
-    enable_embedding: z.boolean().optional(),
-    embedding_type: z.string().optional(),
-    embedding_params: z.unknown().optional(),
+    archived: z.boolean().nullable().optional(),
+    enable_embedding: z.boolean().nullable().optional(),
+    embedding_type: z.string().nullable().optional(),
+    embedding_params: EmbeddingParams.nullable().optional(),
     collection_id: z.number().int().positive().nullable().optional(),
     collection_position: z.number().int().positive().nullable().optional(),
-    collection_preview: z.boolean().optional(),
+    collection_preview: z.boolean().nullable().optional(),
     cache_ttl: z.number().int().positive().nullable().optional(),
     dashboard_id: z.number().int().positive().nullable().optional(),
     dashboard_tab_id: z.number().int().positive().nullable().optional(),
-    parameters: z.array(Parameter).optional(),
-    parameter_mappings: z.array(ParameterMapping).optional(),
+    parameters: z.array(Parameter).nullable().optional(),
+    parameter_mappings: z.array(ParameterMapping).nullable().optional(),
     result_metadata: z.array(z.unknown()).nullable().optional(),
   })
   .loose();
diff --git a/src/domain/collection.ts b/src/domain/collection.ts
index 33b3c42..2e8b362 100644
--- a/src/domain/collection.ts
+++ b/src/domain/collection.ts
@@ -164,7 +164,7 @@ export const CollectionTreeNode: z.ZodType<CollectionTreeNode> = CollectionTreeN
 export const CollectionCreateInput = z
   .object({
     name: z.string().min(1),
-    description: z.string().nullable().optional(),
+    description: z.string().min(1).nullable().optional(),
     parent_id: z.number().int().positive().nullable().optional(),
     namespace: CollectionNamespace.nullable().optional(),
     authority_level: CollectionAuthorityLevel.nullable().optional(),
diff --git a/src/domain/dashboard.ts b/src/domain/dashboard.ts
index 08f639f..9d3252a 100644
--- a/src/domain/dashboard.ts
+++ b/src/domain/dashboard.ts
@@ -1,5 +1,6 @@
 import { z } from "zod";
 
+import { EmbeddingParams } from "./embedding";
 import { Parameter, ParameterMapping } from "./parameter";
 import type { ResourceView } from "./view";
 
@@ -119,34 +120,61 @@ export const dashboardView: ResourceView<Dashboard> = {
   ],
 };
 
+const DashcardWrite = z
+  .object({
+    id: z.number().int().describe("existing dashcard id; negative to create a new dashcard"),
+    size_x: z.number().int().positive(),
+    size_y: z.number().int().positive(),
+    row: z.number().int().nonnegative(),
+    col: z.number().int().nonnegative(),
+    parameter_mappings: z.array(ParameterMapping).nullable().optional(),
+    inline_parameters: z.array(z.string().min(1)).nullable().optional(),
+    series: z.array(z.record(z.string(), z.unknown())).nullable().optional(),
+  })
+  .loose();
+
+const DashboardTabWrite = z
+  .object({
+    id: z.number().int().describe("existing tab id; negative to create a new tab"),
+    name: z.string().min(1),
+  })
+  .loose();
+
+// The server's POST /api/dashboard takes no dashcards/tabs; the create command
+// accepts them anyway and applies them through a follow-up PUT.
 export const DashboardCreateInput = z
   .object({
     name: z.string().min(1),
     description: z.string().nullable().optional(),
-    parameters: z.array(Parameter).optional(),
-    cache_ttl: z.number().int().positive().optional(),
+    parameters: z.array(Parameter).nullable().optional(),
+    cache_ttl: z.number().int().positive().nullable().optional(),
     collection_id: z.number().int().positive().nullable().optional(),
     collection_position: z.number().int().positive().nullable().optional(),
-    dashcards: z.array(z.unknown()).optional(),
-    tabs: z.array(DashboardTab.partial()).optional(),
+    dashcards: z.array(DashcardWrite).optional(),
+    tabs: z.array(DashboardTabWrite).optional(),
   })
   .loose();
 export type DashboardCreateInput = z.infer<typeof DashboardCreateInput>;
 
 export const DashboardUpdateInput = z
   .object({
-    name: z.string().min(1).optional(),
+    name: z.string().min(1).nullable().optional(),
     description: z.string().nullable().optional(),
-    archived: z.boolean().optional(),
+    caveats: z.string().nullable().optional(),
+    points_of_interest: z.string().nullable().optional(),
+    show_in_getting_started: z.boolean().nullable().optional(),
+    archived: z.boolean().nullable().optional(),
+    position: z.number().int().positive().nullable().optional(),
     width: DashboardWidth.optional(),
-    enable_embedding: z.boolean().optional(),
-    embedding_params: z.unknown().optional(),
-    parameters: z.array(Parameter).optional(),
+    enable_embedding: z.boolean().nullable().optional(),
+    embedding_type: z.string().nullable().optional(),
+    embedding_params: EmbeddingParams.nullable().optional(),
+    parameters: z.array(Parameter).nullable().optional(),
     cache_ttl: z.number().int().positive().nullable().optional(),
     collection_id: z.number().int().positive().nullable().optional(),
     collection_position: z.number().int().positive().nullable().optional(),
-    dashcards: z.array(z.unknown()).optional(),
-    tabs: z.array(DashboardTab.partial()).optional(),
+    dashcards: z.array(DashcardWrite).nullable().optional(),
+    tabs: z.array(DashboardTabWrite).nullable().optional(),
   })
   .loose();
 export type DashboardUpdateInput = z.infer<typeof DashboardUpdateInput>;
@@ -158,10 +186,10 @@ export const DashcardPatchInput = z
     size_x: z.number().int().positive().optional(),
     size_y: z.number().int().positive().optional(),
     dashboard_tab_id: z.number().int().nullable().optional(),
-    parameter_mappings: z.array(ParameterMapping).optional(),
-    inline_parameters: z.array(z.string()).optional(),
+    parameter_mappings: z.array(ParameterMapping).nullable().optional(),
+    inline_parameters: z.array(z.string().min(1)).nullable().optional(),
     visualization_settings: z.unknown().optional(),
-    series: z.array(z.unknown()).optional(),
+    series: z.array(z.record(z.string(), z.unknown())).nullable().optional(),
   })
   .strict()
   .refine((value) => Object.keys(value).length > 0, {
diff --git a/src/domain/document.ts b/src/domain/document.ts
index 6b99bc2..b379605 100644
--- a/src/domain/document.ts
+++ b/src/domain/document.ts
@@ -90,23 +90,53 @@ export const documentView: ResourceView<Document> = {
   ],
 };
 
-export const DocumentCreateInput = z
+const DocumentName = z.string().min(1).max(254);
+
+const DocumentCardInput = z
   .object({
     name: z.string().min(1),
+    dataset_query: z.record(z.string(), z.unknown()),
+    display: z.string().min(1),
+    visualization_settings: z.record(z.string(), z.unknown()),
+    entity_id: z.string().min(1).nullable().optional(),
+    parameters: z.array(z.record(z.string(), z.unknown())).nullable().optional(),
+    parameter_mappings: z.array(z.record(z.string(), z.unknown())).nullable().optional(),
+    description: z.string().min(1).nullable().optional(),
+    result_metadata: z.array(z.record(z.string(), z.unknown())).nullable().optional(),
+    cache_ttl: z.number().int().positive().nullable().optional(),
+  })
+  .loose();
+
+const NEW_CARD_KEY_DESCRIPTION =
+  "cards to create inline, keyed by the negative placeholder id referenced from cardEmbed nodes";
+
+export const DocumentCreateInput = z
+  .object({
+    name: DocumentName,
     document: TipTapNodeInput,
     collection_id: z.number().int().positive().nullable().optional(),
     collection_position: z.number().int().positive().nullable().optional(),
+    cards: z
+      .record(z.string().regex(/^-\d+$/), DocumentCardInput)
+      .nullable()
+      .optional()
+      .describe(NEW_CARD_KEY_DESCRIPTION),
   })
   .loose();
 export type DocumentCreateInput = z.infer<typeof DocumentCreateInput>;
 
 export const DocumentUpdateInput = z
   .object({
-    name: z.string().min(1).optional(),
+    name: DocumentName.optional(),
     document: TipTapNodeInput.optional(),
     collection_id: z.number().int().positive().nullable().optional(),
     collection_position: z.number().int().positive().nullable().optional(),
     archived: z.boolean().nullable().optional(),
+    cards: z
+      .record(z.string().regex(/^-?\d+$/), DocumentCardInput)
+      .nullable()
+      .optional()
+      .describe("cards keyed by card id; negative ids create new cards"),
   })
   .loose();
 export type DocumentUpdateInput = z.infer<typeof DocumentUpdateInput>;
diff --git a/src/domain/eid-translation.ts b/src/domain/eid-translation.ts
index 648abae..817342a 100644
--- a/src/domain/eid-translation.ts
+++ b/src/domain/eid-translation.ts
@@ -32,7 +32,7 @@ export const EidTranslateInput = z
   .object({
     // partialRecord (not record) — Zod 4's z.record(enum, …) treats every
     // enum key as required, but the API accepts any subset of models.
-    entity_ids: z.partialRecord(EidModel, z.array(z.string().min(1)).min(1)),
+    entity_ids: z.partialRecord(EidModel, z.array(z.string().length(21))),
   })
   .loose();
 export type EidTranslateInput = z.infer<typeof EidTranslateInput>;
diff --git a/src/domain/embedding.ts b/src/domain/embedding.ts
new file mode 100644
index 0000000..1e7ba85
--- /dev/null
+++ b/src/domain/embedding.ts
@@ -0,0 +1,4 @@
+import { z } from "zod";
+
+export const EmbeddingParams = z.record(z.string(), z.enum(["disabled", "enabled", "locked"]));
+export type EmbeddingParams = z.infer<typeof EmbeddingParams>;
diff --git a/src/domain/field.ts b/src/domain/field.ts
index f5d66a0..472590d 100644
--- a/src/domain/field.ts
+++ b/src/domain/field.ts
@@ -113,6 +113,8 @@ export const FieldSemanticType = z.enum([
   "type/Birthdate",
   "type/Structured",
   "type/SerializedJSON",
+  "type/JSON",
+  "type/DruidJSON",
   "type/XML",
   "type/User",
   "type/Author",
@@ -203,17 +205,17 @@ const NonBlankNullable = z.string().min(1).nullable();
 
 export const FieldUpdateInput = z
   .object({
-    display_name: z.string().min(1).optional(),
+    display_name: NonBlankNullable.optional(),
     description: NonBlankNullable.optional(),
     caveats: NonBlankNullable.optional(),
     points_of_interest: NonBlankNullable.optional(),
     semantic_type: FieldSemanticType.nullable().optional(),
     coercion_strategy: FieldCoercionStrategy.nullable().optional(),
     fk_target_field_id: z.number().int().positive().nullable().optional(),
-    visibility_type: FieldVisibilityType.optional(),
-    has_field_values: FieldValuesType.optional(),
+    visibility_type: FieldVisibilityType.nullable().optional(),
+    has_field_values: FieldValuesType.nullable().optional(),
     settings: z.record(z.string(), z.unknown()).nullable().optional(),
-    nfc_path: z.array(z.string()).nullable().optional(),
+    nfc_path: z.array(z.string().min(1)).nullable().optional(),
     json_unfolding: z.boolean().nullable().optional(),
   })
   .loose();
diff --git a/src/domain/measure.ts b/src/domain/measure.ts
index 21d1d58..266298b 100644
--- a/src/domain/measure.ts
+++ b/src/domain/measure.ts
@@ -42,11 +42,17 @@ export const measureView: ResourceView<Measure> = {
   ],
 };
 
+const MeasureDefinition = z
+  .record(z.string(), z.unknown())
+  .describe(
+    "MBQL query holding exactly one aggregation — full MBQL 5 schema: mb query --print-schema",
+  );
+
 export const MeasureCreateInput = z
   .object({
     name: z.string().min(1),
     table_id: z.number().int().positive(),
-    definition: z.record(z.string(), z.unknown()),
+    definition: MeasureDefinition,
     description: z.string().nullable().optional(),
   })
   .loose();
@@ -54,10 +60,10 @@ export type MeasureCreateInput = z.infer<typeof MeasureCreateInput>;
 
 export const MeasureUpdateInput = z
   .object({
-    name: z.string().min(1).optional(),
-    definition: z.record(z.string(), z.unknown()).optional(),
+    name: z.string().min(1).nullable().optional(),
+    definition: MeasureDefinition.nullable().optional(),
     revision_message: z.string().min(1),
-    archived: z.boolean().optional(),
+    archived: z.boolean().nullable().optional(),
     description: z.string().nullable().optional(),
   })
   .loose();
diff --git a/src/domain/segment.ts b/src/domain/segment.ts
index 2754272..03fa1d2 100644
--- a/src/domain/segment.ts
+++ b/src/domain/segment.ts
@@ -42,11 +42,15 @@ export const segmentView: ResourceView<Segment> = {
   ],
 };
 
+const SegmentDefinition = z
+  .record(z.string(), z.unknown())
+  .describe("MBQL query holding the filter — full MBQL 5 schema: mb query --print-schema");
+
 export const SegmentCreateInput = z
   .object({
     name: z.string().min(1),
     table_id: z.number().int().positive(),
-    definition: z.record(z.string(), z.unknown()),
+    definition: SegmentDefinition,
     description: z.string().nullable().optional(),
   })
   .loose();
@@ -54,14 +58,14 @@ export type SegmentCreateInput = z.infer<typeof SegmentCreateInput>;
 
 export const SegmentUpdateInput = z
   .object({
-    name: z.string().min(1).optional(),
-    definition: z.record(z.string(), z.unknown()).optional(),
+    name: z.string().min(1).nullable().optional(),
+    definition: SegmentDefinition.nullable().optional(),
     revision_message: z.string().min(1),
-    archived: z.boolean().optional(),
+    archived: z.boolean().nullable().optional(),
     description: z.string().nullable().optional(),
     caveats: z.string().nullable().optional(),
     points_of_interest: z.string().nullable().optional(),
-    show_in_getting_started: z.boolean().optional(),
+    show_in_getting_started: z.boolean().nullable().optional(),
   })
   .loose();
 export type SegmentUpdateInput = z.infer<typeof SegmentUpdateInput>;
diff --git a/src/domain/setup.ts b/src/domain/setup.ts
index 5cd63a2..f41d340 100644
--- a/src/domain/setup.ts
+++ b/src/domain/setup.ts
@@ -4,10 +4,13 @@ import type { ResourceView } from "./view";
 
 const SetupUserInput = z
   .object({
-    first_name: z.string().nullable().optional(),
-    last_name: z.string().nullable().optional(),
-    email: z.string().min(1),
-    password: z.string().min(1),
+    first_name: z.string().min(1).nullable().optional(),
+    last_name: z.string().min(1).nullable().optional(),
+    email: z.email(),
+    password: z
+      .string()
+      .min(1)
+      .describe("must satisfy the server's password complexity requirements"),
   })
   .loose();
 
diff --git a/src/domain/snippet.ts b/src/domain/snippet.ts
index d9ff715..8d39cd3 100644
--- a/src/domain/snippet.ts
+++ b/src/domain/snippet.ts
@@ -39,9 +39,13 @@ export const snippetView: ResourceView<Snippet> = {
   ],
 };
 
+const SNIPPET_NAME_PATTERN = /^(?!\s)[^}]*$/;
+const SNIPPET_NAME_MESSAGE = "snippet names cannot include '}' or start with spaces";
+const snippetName = z.string().regex(SNIPPET_NAME_PATTERN, SNIPPET_NAME_MESSAGE);
+
 export const SnippetCreateInput = z
   .object({
-    name: z.string().min(1),
+    name: snippetName,
     content: z.string(),
     description: z.string().nullable().optional(),
     collection_id: z.number().int().positive().nullable().optional(),
@@ -51,10 +55,10 @@ export type SnippetCreateInput = z.infer<typeof SnippetCreateInput>;
 
 export const SnippetUpdateInput = z
   .object({
-    name: z.string().min(1).optional(),
-    content: z.string().optional(),
+    name: snippetName.nullable().optional(),
+    content: z.string().nullable().optional(),
     description: z.string().nullable().optional(),
-    archived: z.boolean().optional(),
+    archived: z.boolean().nullable().optional(),
     collection_id: z.number().int().positive().nullable().optional(),
   })
   .loose();
diff --git a/src/domain/table.ts b/src/domain/table.ts
index 54f7275..adf9c66 100644
--- a/src/domain/table.ts
+++ b/src/domain/table.ts
@@ -69,16 +69,24 @@ export const tableView: ResourceView<Table> = {
   ],
 };
 
+const TableDataAuthority = z.enum(["unconfigured", "authoritative", "computed", "ingested"]);
+
 export const TableUpdateInput = z
   .object({
-    display_name: z.string().min(1).optional(),
+    display_name: z.string().min(1).nullable().optional(),
     entity_type: TableEntityType.nullable().optional(),
     visibility_type: TableVisibilityType.nullable().optional(),
     description: z.string().nullable().optional(),
     caveats: z.string().nullable().optional(),
     points_of_interest: z.string().nullable().optional(),
-    show_in_getting_started: z.boolean().optional(),
-    field_order: TableFieldOrder.optional(),
+    show_in_getting_started: z.boolean().nullable().optional(),
+    field_order: TableFieldOrder.nullable().optional(),
+    data_authority: TableDataAuthority.nullable().optional(),
+    data_source: z.string().nullable().optional(),
+    data_layer: z.string().nullable().optional(),
+    owner_email: z.string().nullable().optional(),
+    owner_user_id: z.number().int().nullable().optional(),
+    collection_id: z.number().int().positive().nullable().optional(),
   })
   .loose();
 export type TableUpdateInput = z.infer<typeof TableUpdateInput>;
diff --git a/src/domain/transform.ts b/src/domain/transform.ts
index edfb42e..b12db9b 100644
--- a/src/domain/transform.ts
+++ b/src/domain/transform.ts
@@ -17,10 +17,30 @@ const TransformRunMethod = z.enum(["manual", "cron"]);
 
 const TransformRunTrigger = z.enum(["none", "global-schedule"]);
 
+const TransformCheckpointStrategy = z
+  .object({
+    type: z.literal("checkpoint"),
+    "checkpoint-filter-field-id": z.number().int().positive().optional(),
+  })
+  .loose();
+
+const TransformSourceTableEntry = z
+  .object({
+    alias: z.string(),
+    database_id: z.number().int(),
+    schema: z.string().nullable(),
+    table: z.string().optional(),
+    table_id: z.number().int().nullable().optional(),
+  })
+  .loose();
+
 const TransformQuerySource = z
   .object({
     type: z.literal("query"),
-    query: z.unknown(),
+    query: z
+      .unknown()
+      .describe("Native SQL or MBQL query — full MBQL 5 schema: mb query --print-schema"),
+    "source-incremental-strategy": TransformCheckpointStrategy.optional(),
   })
   .loose();
 
@@ -28,16 +48,40 @@ const TransformPythonSource = z
   .object({
     type: z.literal("python"),
     body: z.string(),
+    "source-tables": z.array(TransformSourceTableEntry),
+    "source-database": z.number().int().optional(),
+    "source-incremental-strategy": TransformCheckpointStrategy.optional(),
   })
   .loose();
 
 const TransformSource = z.discriminatedUnion("type", [TransformQuerySource, TransformPythonSource]);
 
+const TransformAppendStrategy = z.object({ type: z.literal("append") }).loose();
+
+const TransformMergeKeyColumn = z
+  .object({
+    name: z.string().min(1).optional(),
+    "field-id": z.number().int().positive().nullable().optional(),
+  })
+  .loose();
+
+const TransformMergeStrategy = z
+  .object({
+    type: z.literal("merge"),
+    "unique-key": z.array(TransformMergeKeyColumn),
+  })
+  .loose();
+
+const TransformTargetIncrementalStrategy = z.discriminatedUnion("type", [
+  TransformAppendStrategy,
+  TransformMergeStrategy,
+]);
+
 const TransformTableTarget = z
   .object({
     type: z.literal("table"),
     database: z.number().int().optional(),
-    schema: z.string().nullable().optional(),
+    schema: z.string().min(1).nullable().optional(),
     name: z.string(),
   })
   .loose();
@@ -46,8 +90,9 @@ const TransformTableIncrementalTarget = z
   .object({
     type: z.literal("table-incremental"),
     database: z.number().int().optional(),
-    schema: z.string().nullable().optional(),
+    schema: z.string().min(1).nullable().optional(),
     name: z.string(),
+    "target-incremental-strategy": TransformTargetIncrementalStrategy,
   })
   .loose();
 
diff --git a/src/main.ts b/src/main.ts
index 83332c3..dfef374 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -50,6 +50,7 @@ setMetabaseAugment(main, {
       purpose: "guided end-to-end: raw data → clean tables → metrics → answers → dashboards",
     },
   ],
+  inputSchema: null,
   outputSchema: null,
   capabilities: null,
 });
diff --git a/src/output/help.test.ts b/src/output/help.test.ts
index cbff889..3062bf5 100644
--- a/src/output/help.test.ts
+++ b/src/output/help.test.ts
@@ -326,6 +326,7 @@ describe("showUsage", () => {
       examples: [],
       details: null,
       skills: [{ skill: "core", purpose: "auth and conventions" }],
+      inputSchema: null,
       outputSchema: null,
       capabilities: null,
     });
@@ -416,6 +417,7 @@ describe("showUsageJson", () => {
       skills: [],
       examples: ["mb foo bar --json"],
       args: [],
+      inputSchema: null,
       outputSchema: {
         $schema: "https://json-schema.org/draft/2020-12/schema",
         type: "object",
diff --git a/src/runtime/command-augment.test.ts b/src/runtime/command-augment.test.ts
index 7d0096a..2e9ffd1 100644
--- a/src/runtime/command-augment.test.ts
+++ b/src/runtime/command-augment.test.ts
@@ -17,6 +17,7 @@ describe("getMetabaseAugment / setMetabaseAugment", () => {
       examples: ["mb card list"],
       details: "see mb skills get mbql",
       skills: [],
+      inputSchema: null,
       outputSchema: z.object({ id: z.number() }),
       capabilities: BASELINE_CAPABILITIES,
     };
@@ -31,6 +32,7 @@ describe("getMetabaseAugment / setMetabaseAugment", () => {
       examples: ["a"],
       details: null,
       skills: [],
+      inputSchema: null,
       outputSchema: null,
       capabilities: BASELINE_CAPABILITIES,
     };
@@ -38,6 +40,7 @@ describe("getMetabaseAugment / setMetabaseAugment", () => {
       examples: ["b"],
       details: null,
       skills: [],
+      inputSchema: null,
       outputSchema: null,
       capabilities: BASELINE_CAPABILITIES,
     };
@@ -53,6 +56,7 @@ describe("getMetabaseAugment / setMetabaseAugment", () => {
       examples: ["before"],
       details: null,
       skills: [],
+      inputSchema: null,
       outputSchema: null,
       capabilities: BASELINE_CAPABILITIES,
     };
@@ -60,6 +64,7 @@ describe("getMetabaseAugment / setMetabaseAugment", () => {
       examples: ["after"],
       details: null,
       skills: [],
+      inputSchema: null,
       outputSchema: null,
       capabilities: BASELINE_CAPABILITIES,
     };
@@ -74,6 +79,7 @@ describe("getMetabaseAugment / setMetabaseAugment", () => {
       examples: [],
       details: null,
       skills: [],
+      inputSchema: null,
       outputSchema: null,
       capabilities: BASELINE_CAPABILITIES,
     };
@@ -83,6 +89,7 @@ describe("getMetabaseAugment / setMetabaseAugment", () => {
       examples: [],
       details: null,
       skills: [],
+      inputSchema: null,
       outputSchema: null,
       capabilities: BASELINE_CAPABILITIES,
     });
diff --git a/src/runtime/command-augment.ts b/src/runtime/command-augment.ts
index dd38891..997249e 100644
--- a/src/runtime/command-augment.ts
+++ b/src/runtime/command-augment.ts
@@ -11,6 +11,7 @@ export interface MetabaseAugment {
   examples: readonly string[];
   details: string | null;
   skills: readonly SkillPointer[];
+  inputSchema: ZodType | null;
   outputSchema: ZodType | null;
   capabilities: Capabilities | null;
 }
diff --git a/src/runtime/command-help.test.ts b/src/runtime/command-help.test.ts
index 128055e..b1ff5b5 100644
--- a/src/runtime/command-help.test.ts
+++ b/src/runtime/command-help.test.ts
@@ -132,6 +132,7 @@ describe("buildHelpEntry", () => {
       skills: [],
       examples: ["root leaf --json"],
       args: [],
+      inputSchema: null,
       outputSchema: {
         $schema: "https://json-schema.org/draft/2020-12/schema",
         type: "object",
@@ -146,6 +147,29 @@ describe("buildHelpEntry", () => {
     });
   });
 
+  it("emits the JSON Schema of inputSchema for commands that declare a body contract", async () => {
+    const leaf = defineMetabaseCommand({
+      meta: { name: "create", description: "create" },
+      args: {},
+      inputSchema: z.object({ name: z.string() }),
+      run() {
+        return;
+      },
+    });
+
+    const entry = await buildHelpEntry(leaf, ["create"]);
+
+    expect(entry.inputSchema).toEqual({
+      $schema: "https://json-schema.org/draft/2020-12/schema",
+      type: "object",
+      properties: {
+        name: { type: "string" },
+      },
+      required: ["name"],
+      additionalProperties: false,
+    });
+  });
+
   it("forwards details for metabase commands that declare it and omits the key otherwise", async () => {
     const withDetails = defineMetabaseCommand({
       meta: { name: "with", description: "short" },
@@ -211,6 +235,7 @@ describe("buildHelpEntry", () => {
       skills: [],
       examples: [],
       args: [],
+      inputSchema: null,
       outputSchema: null,
       capabilities: null,
     });
@@ -365,6 +390,15 @@ describe("command tree contract", () => {
     }
   });
 
+  it("declares an input schema on every command that accepts a JSON body", async () => {
+    for (const entry of await allEntries()) {
+      const acceptsBody = entry.args.some((arg) => arg.name === "body");
+      if (acceptsBody) {
+        expect(entry.inputSchema, `missing inputSchema for ${entry.command}`).not.toBeNull();
+      }
+    }
+  });
+
   it("gates every measure command at v59 and keeps card commands at baseline", async () => {
     const entries = await allEntries();
     const measureCapabilities = Object.fromEntries(
diff --git a/src/runtime/command-help.ts b/src/runtime/command-help.ts
index 2c20c8f..abcb89b 100644
--- a/src/runtime/command-help.ts
+++ b/src/runtime/command-help.ts
@@ -29,6 +29,7 @@ export const CommandHelpEntry = z.object({
   skills: z.array(CommandHelpSkill),
   examples: z.array(z.string()),
   args: z.array(CommandHelpArg),
+  inputSchema: z.unknown().nullable(),
   outputSchema: z.unknown().nullable(),
   capabilities: Capabilities.nullable(),
 });
@@ -49,6 +50,7 @@ const EMPTY_AUGMENT: MetabaseAugment = {
   examples: [],
   details: null,
   skills: [],
+  inputSchema: null,
   outputSchema: null,
   capabilities: null,
 };
@@ -66,6 +68,7 @@ export async function buildHelpEntry<T extends ArgsDef = ArgsDef>(
     skills: Array.from(augment.skills),
     examples: Array.from(augment.examples),
     args: convertArgs(args),
+    inputSchema: augment.inputSchema ? z.toJSONSchema(augment.inputSchema) : null,
     outputSchema: augment.outputSchema ? z.toJSONSchema(augment.outputSchema) : null,
     capabilities: augment.capabilities,
   };