diff --git a/packages/mcp-core/src/constants.ts b/packages/mcp-core/src/constants.ts
index 487bd04c5..85cef2495 100644
--- a/packages/mcp-core/src/constants.ts
+++ b/packages/mcp-core/src/constants.ts
@@ -14,6 +14,7 @@ export const MCP_SERVER_NAME = "Sentry MCP" as const;
  * Intentionally bounded for query performance; lower-level API methods still accept arbitrary Sentry statsPeriod strings.
  */
 export const SEARCH_ISSUES_PERIOD_VALUES = [
+  "1h",
   "24h",
   "7d",
   "14d",
diff --git a/packages/mcp-core/src/schema.test.ts b/packages/mcp-core/src/schema.test.ts
new file mode 100644
index 000000000..a3e7373de
--- /dev/null
+++ b/packages/mcp-core/src/schema.test.ts
@@ -0,0 +1,30 @@
+import { describe, expect, it } from "vitest";
+import { ParamOrganizationSlug, ParamPeriod } from "./schema";
+
+describe("ParamPeriod", () => {
+  it.each(["30m", "1h", "24h", "7d", "2w"])("accepts %s", (period) => {
+    expect(ParamPeriod.parse(period)).toBe(period);
+  });
+
+  it.each(["1mo", "last hour", "1.5h"])("rejects %s", (period) => {
+    expect(ParamPeriod.safeParse(period).success).toBe(false);
+  });
+});
+
+describe("ParamOrganizationSlug", () => {
+  it.each([undefined, null])("explains how to recover a %s slug", (value) => {
+    const result = ParamOrganizationSlug.safeParse(value);
+
+    expect(result.error?.issues[0]?.message).toBe(
+      "Required. Call `find_organizations()` to list your organizations, then retry with `organizationSlug` set to one of their slugs.",
+    );
+  });
+
+  it("keeps the type message for non-string slugs", () => {
+    const result = ParamOrganizationSlug.safeParse(42);
+
+    expect(result.error?.issues[0]?.message).toBe(
+      "Invalid input: expected string, received number",
+    );
+  });
+});
diff --git a/packages/mcp-core/src/schema.ts b/packages/mcp-core/src/schema.ts
index 6f5d4702c..fb86c4381 100644
--- a/packages/mcp-core/src/schema.ts
+++ b/packages/mcp-core/src/schema.ts
@@ -12,7 +12,14 @@ import { validateResourceId, validateSlug } from "./utils/slug-validation";
 // Sentry slug lookups can be exact and case-sensitive on legacy instances.
 // Preserve caller casing for resource slugs; only trim and validate shape.
 export const ParamOrganizationSlug = z
-  .string()
+  .string({
+    // The MCP SDK rejects a missing slug before the handler runs, so this
+    // message is the only recovery hint the caller gets.
+    error: (issue) =>
+      issue.input == null
+        ? "Required. Call `find_organizations()` to list your organizations, then retry with `organizationSlug` set to one of their slugs."
+        : undefined,
+  })
   .trim()
   .superRefine(validateSlug)
   .describe(
@@ -142,11 +149,11 @@ export const ParamPeriod = z
   .string()
   .trim()
   .regex(
-    /^\d+[hdw]$/,
-    "Period must be a relative time window like `24h`, `7d`, `14d`, `30d`, or `90d`.",
+    /^\d+[mhdw]$/,
+    "Period must be a relative time window like `30m` (minutes), `1h`, `24h`, `7d`, or `90d`.",
   )
   .describe(
-    "Relative time window, such as `24h`, `7d`, `14d`, `30d`, or `90d`. Controls which records fall within the search window.",
+    "Relative time window, such as `30m`, `1h`, `24h`, `7d`, or `90d`. Controls which records fall within the search window.",
   );
 
 /**
diff --git a/packages/mcp-core/src/server.test.ts b/packages/mcp-core/src/server.test.ts
index a6425f7d4..1256b4f09 100644
--- a/packages/mcp-core/src/server.test.ts
+++ b/packages/mcp-core/src/server.test.ts
@@ -252,6 +252,26 @@ describe("buildServer", () => {
     });
   });
 
+  it.each(["v1", "v2"] as const)(
+    "explains how to recover a missing organizationSlug on SDK %s",
+    async (sdkVersion) => {
+      const server =
+        sdkVersion === "v2"
+          ? buildServer({ context: baseContext, sdkVersion })
+          : buildServer({ context: baseContext });
+
+      const result = await callRegisteredTool(server, "search_issues", {
+        query: "is:unresolved",
+        period: "1h",
+      });
+
+      expect(result).toMatchObject({ isError: true });
+      const text = getTextContent(result);
+      expect(text).toContain("Required. Call `find_organizations()`");
+      expect(text).not.toContain("period");
+    },
+  );
+
   describe("telemetry context", () => {
     it("generates compatibility text for structured-only tool output", async () => {
       const server = buildServer({
diff --git a/packages/mcp-core/src/toolDefinitions.json b/packages/mcp-core/src/toolDefinitions.json
index 50d8ec298..14cdea45f 100644
--- a/packages/mcp-core/src/toolDefinitions.json
+++ b/packages/mcp-core/src/toolDefinitions.json
@@ -5213,7 +5213,7 @@
           "anyOf": [
             {
               "type": "string",
-              "pattern": "^\\d+[hdw]$",
+              "pattern": "^\\d+[mhdw]$",
               "description": "Relative time range. Defaults to `24h` when `start` and `end` are omitted."
             },
             {
@@ -5321,12 +5321,12 @@
           "default": "7d",
           "description": "Profiling time window (default: '7d'). Use '1h' for very recent profiling data.",
           "type": "string",
-          "pattern": "^\\d+[hdw]$"
+          "pattern": "^\\d+[mhdw]$"
         },
         "compareAgainstPeriod": {
           "description": "Compare against this baseline profiling time window. Enables regression detection.",
           "type": "string",
-          "pattern": "^\\d+[hdw]$"
+          "pattern": "^\\d+[mhdw]$"
         },
         "focusOnUserCode": {
           "default": true,
@@ -5761,7 +5761,7 @@
         },
         "period": {
           "type": "string",
-          "pattern": "^\\d+[hdw]$",
+          "pattern": "^\\d+[mhdw]$",
           "description": "Relative time range for recent checks. Defaults to `24h` when `start` and `end` are omitted."
         },
         "start": {
@@ -6198,7 +6198,7 @@
           "default": "30d",
           "description": "Relative time range. Defaults to 30d.",
           "type": "string",
-          "pattern": "^\\d+[hdw]$"
+          "pattern": "^\\d+[mhdw]$"
         },
         "start": {
           "description": "Explicit start time for the search window.",
@@ -6421,7 +6421,7 @@
           "default": "30d",
           "description": "Relative time range. Defaults to 30d.",
           "type": "string",
-          "pattern": "^\\d+[hdw]$"
+          "pattern": "^\\d+[mhdw]$"
         },
         "start": {
           "description": "Explicit start time for the search window.",
@@ -6796,8 +6796,8 @@
         },
         "period": {
           "type": "string",
-          "pattern": "^\\d+[hdw]$",
-          "description": "Relative time window, such as `24h`, `7d`, `14d`, `30d`, or `90d`. Controls which records fall within the search window."
+          "pattern": "^\\d+[mhdw]$",
+          "description": "Relative time window, such as `30m`, `1h`, `24h`, `7d`, or `90d`. Controls which records fall within the search window."
         },
         "regionUrl": {
           "default": null,
@@ -6898,8 +6898,8 @@
         },
         "period": {
           "type": "string",
-          "pattern": "^\\d+[hdw]$",
-          "description": "Relative time window, such as `24h`, `7d`, `14d`, `30d`, or `90d`. Controls which records fall within the search window."
+          "pattern": "^\\d+[mhdw]$",
+          "description": "Relative time window, such as `30m`, `1h`, `24h`, `7d`, or `90d`. Controls which records fall within the search window."
         },
         "regionUrl": {
           "default": null,
@@ -6970,8 +6970,8 @@
         },
         "period": {
           "type": "string",
-          "pattern": "^\\d+[hdw]$",
-          "description": "Relative time window, such as `24h`, `7d`, `14d`, `30d`, or `90d`. Controls which records fall within the search window."
+          "pattern": "^\\d+[mhdw]$",
+          "description": "Relative time window, such as `30m`, `1h`, `24h`, `7d`, or `90d`. Controls which records fall within the search window."
         },
         "projectSlug": {
           "default": null,
@@ -7064,9 +7064,9 @@
         },
         "period": {
           "default": "30d",
-          "description": "Time window for issue search results. Controls which issues are returned based on when they had activity. Default 30d is a balance between coverage and query performance; use 24h for very recent issues or 90d for broader historical searches.",
+          "description": "Time window for issue search results. Controls which issues are returned based on when they had activity. Default 30d is a balance between coverage and query performance; use 1h or 24h for very recent issues or 90d for broader historical searches.",
           "type": "string",
-          "enum": ["24h", "7d", "14d", "30d", "90d"]
+          "enum": ["1h", "24h", "7d", "14d", "30d", "90d"]
         },
         "includeExplanation": {
           "default": false,
@@ -7126,8 +7126,8 @@
         },
         "period": {
           "type": "string",
-          "pattern": "^\\d+[hdw]$",
-          "description": "Relative time window, such as `24h`, `7d`, `14d`, `30d`, or `90d`. Controls which records fall within the search window."
+          "pattern": "^\\d+[mhdw]$",
+          "description": "Relative time window, such as `30m`, `1h`, `24h`, `7d`, or `90d`. Controls which records fall within the search window."
         },
         "regionUrl": {
           "default": null,
@@ -7206,8 +7206,8 @@
         },
         "period": {
           "type": "string",
-          "pattern": "^\\d+[hdw]$",
-          "description": "Relative time window, such as `24h`, `7d`, `14d`, `30d`, or `90d`. Controls which records fall within the search window."
+          "pattern": "^\\d+[mhdw]$",
+          "description": "Relative time window, such as `30m`, `1h`, `24h`, `7d`, or `90d`. Controls which records fall within the search window."
         },
         "regionUrl": {
           "default": null,
@@ -7286,8 +7286,8 @@
         },
         "period": {
           "type": "string",
-          "pattern": "^\\d+[hdw]$",
-          "description": "Relative time window, such as `24h`, `7d`, `14d`, `30d`, or `90d`. Controls which records fall within the search window."
+          "pattern": "^\\d+[mhdw]$",
+          "description": "Relative time window, such as `30m`, `1h`, `24h`, `7d`, or `90d`. Controls which records fall within the search window."
         },
         "regionUrl": {
           "default": null,
@@ -7369,8 +7369,8 @@
         },
         "period": {
           "type": "string",
-          "pattern": "^\\d+[hdw]$",
-          "description": "Relative time window, such as `24h`, `7d`, `14d`, `30d`, or `90d`. Controls which records fall within the search window."
+          "pattern": "^\\d+[mhdw]$",
+          "description": "Relative time window, such as `30m`, `1h`, `24h`, `7d`, or `90d`. Controls which records fall within the search window."
         },
         "regionUrl": {
           "default": null,
@@ -7533,8 +7533,8 @@
         },
         "period": {
           "type": "string",
-          "pattern": "^\\d+[hdw]$",
-          "description": "Relative time window, such as `24h`, `7d`, `14d`, `30d`, or `90d`. Controls which records fall within the search window."
+          "pattern": "^\\d+[mhdw]$",
+          "description": "Relative time window, such as `30m`, `1h`, `24h`, `7d`, or `90d`. Controls which records fall within the search window."
         },
         "regionUrl": {
           "default": null,
diff --git a/packages/mcp-core/src/tools/catalog/search-issues.test.ts b/packages/mcp-core/src/tools/catalog/search-issues.test.ts
index 73c740fd0..59f9cd772 100644
--- a/packages/mcp-core/src/tools/catalog/search-issues.test.ts
+++ b/packages/mcp-core/src/tools/catalog/search-issues.test.ts
@@ -113,6 +113,10 @@ describe("search_issues", () => {
     },
   );
 
+  it("accepts a 1h period", () => {
+    expect(searchIssues.inputSchema.period.parse("1h")).toBe("1h");
+  });
+
   it("should search issues with natural language query", async () => {
     mockGenerateText.mockResolvedValue(mockAIResponse("is:unresolved", "date"));
 
diff --git a/packages/mcp-core/src/tools/catalog/search-issues.ts b/packages/mcp-core/src/tools/catalog/search-issues.ts
index 93e8acc5f..749aa4681 100644
--- a/packages/mcp-core/src/tools/catalog/search-issues.ts
+++ b/packages/mcp-core/src/tools/catalog/search-issues.ts
@@ -128,7 +128,7 @@ export default defineTool({
       .enum(SEARCH_ISSUES_PERIOD_VALUES)
       .default("30d")
       .describe(
-        "Time window for issue search results. Controls which issues are returned based on when they had activity. Default 30d is a balance between coverage and query performance; use 24h for very recent issues or 90d for broader historical searches.",
+        "Time window for issue search results. Controls which issues are returned based on when they had activity. Default 30d is a balance between coverage and query performance; use 1h or 24h for very recent issues or 90d for broader historical searches.",
       ),
     includeExplanation: z
       .boolean()